C. PNEUMONIAE SPECIFIC PEPTIDES AND THEIR USE IN DIAGNOSTIC ASSAYS

Abstract: A peptide derived from the variable domain of C. pneumoniae MOMP protein, for use in the diagnosis of C. pneumoniae infections, said peptide comprises between 9-40 amino acids and being able to react with antibodies formed during infection with C. pneumonia, further characterized by having essentially very low cross-reactivity towards antibodies against other Chlamydia species.

Description: C. PNEUMONIAE SPECIFIC PEPTIDES AND THEIR USE IN DIAGNOSTIC ASSAYS Field of the Invention The present invention concerns an improved method and kit for the diagnosis of Chlamydia pneumoniae (C. pneumoniae) in humans. More specifically, the present invention concerns peptides derived from the major outer membrane protein (MOMP), which are capable of specifically reacting with antibodies specific to C. pneumoniae, and hence said set of peptides is particularly useful for identifying C. pneumoniae infections in humans by binding specifically to antibodies, if present, in a body fluid sample obtained from an individual being tested. Background of the Invention Chlamydia is a gram negative obligate intracellular bacteria that causes acute and chronic disease in mammalian and avian species. The genus Chlamydia is comprised of four species: C. trachomatis, C. pneumoniae, C. precorum and C. psittaci. The bacteria C. psittaci, which occur as parasites in birds, had been identified as causing respiratory disease in humans. Since C. pneumoniae are related to and immunologically cross-reactive with these bacteria, the C. pneumoniae species was originally thought to be a variant of C. psittaci and was called TWAR, after the initials of the first two isolates. However, it was later established that C. pneumoniae is a different species, as shown by differences in DNA and antigenic differences in the major outer membrane protein (MOMP) of the bacteria. Once tools were available to distinguish C. pneumoniae from other bacterial species, it was found that it not only causes pneumonia, but is also associated with bronchitis and sinusitis. Even more importantly, this Chlamydia species has also been shown to be associated with heart disease (acute infarction and chronic coronary heart disease) and arteriosclerosis. In these latter diseases, the infection appears to be chronic, and some studies show that infectious particles could not be recovered from the site of the disease. Detection of C. pneumoniae infection is principally possible in two ways: detection of the bacteria or their components themselves, or detection of antibodies formed against them. For the detection of the bacteria themselves, one possibility is growth of the bacteria in culture, with subsequent identification. In addition, for the direct detection of chlamydial components from patient samples, assays based on detection of chlamydial LPS, DNA or unidentified epitopes (by monoclonal antibodies) have been developed. For the detection of antibodies against Chlamydia, the chlamydial LPS, elementary bodies (infectious Chlamydia particles), and elementary bodies which were chemically treated to destroy the cross- reactive LPS in them, have been used. Serological testing, i.e., the testing for the presence (or not) of anti-C pneumoniae antibodies in an individual, is now an established approach, and has been shown to provide a comprehensive answer for the detection of C. pneumoniae infection. In suspected deep-seated infections, serum sampling reduces the necessity for invasive procedures which are required for direct antigen detection. In cases of suspected pneumonia, collection limitations such as effectiveness of scrape sampling procedure, specimen handling and transportation difficulties have to be weighed. In addition, it must be taken into account that in contrast to C. trachomatis, C. pneumoniae elementary bodies or LPS are scarce in samples taken from the site of infection, e.g. in throat swabs. Even PCR-based methods have been shown to lack sensitivity when throat swabs were used to detect C. pneumoniae infection. Above all, there still remains the problematic issue that most chlamydial infections are asymptomatic. Therefore, an infection may persist for a long time, e.g., descend deeper into the lung, causing deep and chronic infections, which may result in severe complications, and increase the probability of false negative results in procedures designed for direct antigen detection, i.e., sampling of throat swabs. Serological testing for Chlamydia pneumoniae, through the detection of various specific antibodies, is today an effective and highly accepted optional detection procedure. New and refined technologies apply the immuno markers IgM, IgA and IgG to characterize the presence and stage of infection. The detection of specific IgM antibodies is indicative of acute chlamydial infections. The absence does not, however, preclude the presence of ongoing infection, however, especially in recurrent and chronic cases. The detection of specific IgA antibodies might indicate active or persistent chlamydial infection and has been shown to be an important marker because of the shorter lifetime of IgA antibodies which persist only as long as antigenic stimulation exists. IgA antibody detection is, moreover, suitable for post-therapy follow-up. IgG antibody detection is a marker for chlamydial-positive immune-response, either for current, chronic or past infections. The presence of IgA antibodies has been demonstrated to be especially valuable in determining the association between C. pneumoniae and heart diseases, with the likely result that also monitoring or diagnosing of such diseases will benefit from C. pneumoniae IgA measurement, in addition to IgG measurement. There exists a high level of serological cross-reactions between the different species of Chlamydia. Most of the serological diagnostic assays for Chlamydia use either purified elementary bodies (microimmunofluorescence (MIF) and ELISA tests), or lipopolysaccharide (LPS) as antigens. Genus specific epitopes are present in all the above antigens, therefore, low species specificity is observed. Therefore, the differentiation between, e.g., anti-C. pneumoniae and anti-C. trachomatis antibodies using conventional serological screening tests (MIF, ELISA, EIA, etc.) is not effective enough. This differentiation is especially important when establishing Chlamydia as the cause for a deep-seated, chronic infection, e.g. the above-mentioned heart disease. In this case, a long-lasting treatment with specific antibiotics is indicated, and it is of paramount importance to correctly diagnose the causative agent before embarking on such a treatment (lasting between 4 and 8 months). Moreover, even the MIF test, which has a certain degree of specificity, is disadvantageous in that it requires the production of C. pneumoniae elementary bodies as the diagnostic reagent. Because of the difficulties in growing C. pneumoniae in culture, the production of these elementary bodies is time-consuming, laborious and difficult to reproduce. The Prior Art Detection of C. pneumoniae by culturing the bacteria is possible. However, C. pneumoniae is far more difficult to grow in culture than the related C. trachomatis, with best results achieved so far by growth in egg yolk. Even after being successfully cultured, the bacteria still have to be identified, which makes this assay laborious. Other assays rely on detection of chlamydial LPS, e.g. by a convenient enzyme-immunoassay. However, this detection is cross-reactive with other Chlamydia species. Moreover, it has been shown that the amount of LPS in throat swabs is often insufficient for detection by immunoassay. This paucity of antigen in samples obtained from the patient seems to be one of the hallmarks of C. pneumoniae infection. Therefore, serological tests based on detection of anti-C. pneumoniae antibodies have been developed. One type of such assays uses LPS as the diagnostic reagent, either obtained from Chlamydia itself or from mutated enterobacteria (RE-LPS), which cross-reacts with Chlamydia. However, the universal occurrence of LPS and the cross- reactivity with LPS of other types of bacteria is a severe drawback in these kind of assays. When intact Chlamydia, e.g. elementary bodies, were used as antigen, the LPS contained in them still causes cross-reactivity. Destruction of the LPS leads to exposure of other cross-reactive epitopes ~ in chlamydial proteins. This is also one of the disadvantages of the at present commonly used micro-immunofluorescence assay. As a solution to these problems, assays based on C. pneumoniae-specific monoclonal antibodies have been developed which can be used for detection of the bacteria (JP 07016098, to Hitachi, EP 264434 to WRF). One of these antibodies specifically detects C. pneumoniae MOMP protein (EP 699688 to Hitachi). The use of the monoclonal antibodies as diagnostic agent allows the detection of bacterial antigens, with the disadvantages described above. Detection of anti-Chlamydia antibodies formed by the patient using the monoclonal antibody would require a sandwich assay in which the monoclonal antibody binds the Chlamydia elementary bodies or a component of the bacteria, and the complex is then contacted with a sample from the patient in which antibodies can bind to the Chlamydia or chlamydial components. This type of assay still entails all the disadvantages of using chlamydial antigens, as detailed above. A number of publications have described DNA probes specific for C. pneumoniae. One type of such probes is isolated from the Chlamydia DNA itself, e.g. in US 5281518, EP264434 to WRF. The isolation of such probes is obviously dependent on culture of C. pneumoniae, which is difficult to achieve. A solution to this problem was presented by analysis of the chlamydial DNA sequence and identification of regions with low homology to other related bacteria, as described in EP 587331 to Gen-Probe, Inc. However, the use for diagnosis of specific oligonucleotides suitable for hybridization or PCR, although solving the problem of specificity, still suffers from severe lack of sensitivity. Even PCR failed in some cases to detect C. pneumoniae in throat swabs from patients with C. pneumoniae infection. The same deficiency of these tests is expected in the diagnosis of C. pneumoniae-CΑ ised arteriosclerosis and heart diseases, as it has been shown that the bacteria only occur locally. For all of the above reasons, simple, rapid and sensitive assays for the detection of C. pneumoniae infection have not been developed, although in view of the recently found association of C. pneumoniae infection with arteriosclerosis their development appears imperative. With respect to the difficulties of developing a specific serological assay, a recent review comments on the diagnostic reagent that "chemically pure antigens would be ideal" (Saikku, Diagnosis of Acute and Chronic C. pneumoniae Infections , p. 165, 2nd paragraph, in: Orfila, J. Byrne, GI et al., eds, chlamydial Infections, Proceedings on the 8th international symposium on Chlamydia infections, Chantilly, France, 1994., Societa Editrice Esculapio, 40131 Bologna). The major immunodominant antigen of other Chlamydia species, e.g. C. trachomatis, is the major outer membrane protein (MOMP), which was therefore used as the basis of diagnostic assays. Although the C. pneumoniae MOMP protein is structurally similar to the MOMP proteins of the other Chlamydia species, it was found not to be the immunodominant antigen, making it unsuitable as a basis for diagnostic assays (Campbell et al., J. Clin. Microbiol. 28, 1261, 1991). In addition, the antigenic determinants that were localized to C. pneumoniae MOMP were found to be genus- rather than species-specific (Campbell et al., Infect. Immun. 58, 93, 1990; and the above Campbell et al., 1991). The full sequence of the C. pneumoniae MOMP has been published (Melgosa et al., Infect. Immun. 59, 2195-2199 (1991). It has now been found that by choosing certain peptides derived from the C. pneumoniae MOMP sequence, it is possible, first, to obtain a reaction to antibodies of C. pneumoniae-infected patients. This had been thought unlikely, because C. pneumoniae MOMP is considered as not being immunodominant, i.e. not likely to elicit the formation of high-titered antibodies to it. Further, it has now been found that such peptides derived from C. pneumoniae MOMP exhibit very low cross-reactivity with anti-C. trachomatis antibodies, i.e. their cross-reactivity is low enough to allow their use in a specific C. pneumoniae diagnostic assay. Also this was unexpected in view of the prior art, as mentioned above, which teaches that C. pneumoniae MOMP only contains genus-specific epitopes, i.e. epitopes that fully cross-react with other Chlamydia species. Using the new peptides, a simple and rapid enzyme immunoassay can be developed, which presents a solution to the problems of the prior art as outlined above. Accordingly, it is an aim of the present invention to provide a peptide or a mixture of peptides derived from specific regions within the MOMP protein, which peptide or peptides are capable of interacting with antibodies against MOMP from C. pneumoniae. Such peptides or a mixture of peptides are particularly useful for diagnostic assays to detect the presence of anti-MOMP antibodies specific to C. pneumoniae obtained from the body fluids of an individual and being species-specific for C. pneumoniae, such diagnostic assays should essentially provide no false- negative results. Likewise, as the peptides or the mixture of peptides is chosen, in accordance with the present invention, to be specific only to the MOMP of C. pneumoniae and not to MOMP from any other Chlamydia species, use of the peptides in such diagnostic assays should also provide these diagnostic assays as having essentially no false-positive results. Another aim of the present invention is to provide for a diagnostic kit for diagnosing the presence in a body fluid of anti-C. pneumoniae MOMP antibodies of any of the C. pneumoniae strains, this diagnostic kit, using such peptides or a mixture of peptides as noted above, providing fof a highly reliable diagnostic test of test samples being inherently very unlikely to yield false-positive or false-negative results. This diagnostic kit is also specific to anti-C. pneumoniae MOMP antibodies and has an essentially very low cross-reactivity with anti-MOMP antibodies specific to the other species of Chlamydia. It is another object of the present invention to provide for a method of diagnosing Chlamydia or C. pneumoniae infection by detection of anti-C. pneumoniae antibodies in the body fluid of an individual using as test reagent the above-mentioned peptides or mixture of peptides. Other objects and aspects of the present invention will arise from the following detailed disclosure of the invention. In the following detailed disclosure of the invention, there will be provided, amongst other details, the amino acid sequences of the various peptides constituting the mixture of peptides in accordance with the present invention. These sequences will be written in the form of the single letter amino acid code. For the purposes of clarity, the following is the key to this single letter code: Further, as will be appreciated by all skilled artisans, the sequences of the peptides in accordance with the present invention have been derived from the known and published C. pneumoniae MOMP amino acid sequence, e.g. in the above-mentioned article by Melgosa and coworkers. Summary of the Invention The present invention is based on the finding that by designing specific peptides derived from the variable domains of the MOMP protein of C. pneumoniae, it is possible to obtain peptides or a mixture thereof that first, are capable of reacting with antibodies formed in an individual in the course of an infection with C. pneumoniae, and second, are specific to anti- MOMP antibodies specific to the MOMP of C. pneumoniae and which peptides have essentially very low cross-reactivity with anti-MOMP antibodies specific to the MOMP of other Chlamydia species such as C. trachomatis or C. psittaci. Further, it has also been found in accordance with the present invention that by using such peptides or a mixture of peptides in a kit for the diagnosis of C. pneumoniae disease, there is provided a kit having significant sensitivity and specificity towards IgA, IgG or IgM antibodies specific for C. pneumoniae MOMP when present in a test body fluid sample assayed with this kit. Accordingly, the present invention provides peptides and a mixture of peptides derived from the variable domains of the Chlamydia pneumoniae (C. pneumoniae) immunodominant major outer membrane protein (MOMP) for use in diagnosis of C. pneumoniae infection, said peptides and said peptide mixture characterized by having specificity to C. pneumoniae anti-MOMP antibodies and being of essentially very low cross-reactivity with anti-MOMP antibodies of other Chlamydia species and said mixture also characterized by having specificity to anti-MOMP antibodies from all varieties of C. pneumoniae. Preferred peptides or mixture of peptides comprise one to five peptides selected from the group of peptides consisting of: (a) SEQ. ID NO. 1, herein also designated as CplA, having the amino acid sequence: CFSMGAKPTGSAAANYTTAVDRPNPAYNK; (b) SEQ. ID NO. 2, herein also designated as Cp2A, having the amino acid sequence: VKGTTVNANELPNVSLSNGK; (c) SEQ. ID NO. 3, herein also designated as CpVDIII, having the amino acid sequence: AFPLPTDAGVATATGTKS; (d) SEQ. ID NO. 4, herein also designated as Cp4A, having the amino acid sequence: LNLTAWNPSLLGNATALSTTDSFK; (e) SEQ. ID NO. 5, herein also designated as C.p VDI, having the amino acid sequence: NYTTAVDRPN; (f) SEQ. ID NO. 6, herein also designated as C.p VDIV, having the amino acid sequence: SLLGNASTTDSFDFMQIV; (g) SEQ. ID NO. 7, herein also designated as CplAimp, having the amino acid sequence: CFSMGAKPTGSAAANYTTAVDRK; (h) analogs of any one of peptides (a)-(g), wherein said analogs have essentially the same biological activity as said peptides (a)-(g), said analogs having between about 9 to about 40 amino acid residues and differing from said peptides (a)-(g) by having one or more " additions, deletions or substitutions. Analogs may also be obtained by combining an N-terminal part of one peptide with a C-terminal part of another peptide derived from the same variable domain such that the complete sequence will be homologous to the variable domain sequence. (i) peptides derived from the sequence of C. pneumoniae MOMP protein variable domains, which upon testing in an immunoassay in accordance with the teaching of this invention, show species-specific reaction only to antibodies specific to C. pneumoniae, but not to antibodies specific to other chlamydial species. Preferred mixtures of peptides in accordance with the present invention are: A mixture of peptides noted above being a mixture of 4 peptides (a), (b), (c) and (d), or a mixture of one or more of said peptides (a)-(d) with one or more analogs of (a)-(d), wherein, where said mixture contains 4 peptides selected from any of the possible combinations of (a) or analog of (a) + (b) or analog of (b) + (c) or analog of (c) + (d) or analog of (d); A mixture of peptides as noted above being a mixture of 4 peptides (b), (c), (d) and (g), wherein, when said peptides and said analogs constitute said mixture, the mixture contains 4 peptides selected from any of the possible combinations of (b) or analog of (b) + (c) or analog of (c) + (d) or analog of (d) + (g) or analog of (g). A mixture of peptides as noted above being a mixture of said peptides (a), (b), (c) and (d), or a mixture of said peptides (b), (c), (d) and (g), wherein said peptides are present in said mixture in equal amounts. The present invention also provides the said peptides conjugated directly or indirectly (e.g., via beads and/or linkers) to a detectable marker, such as, for example, a radioactive label, an enzyme, avidin or a derivative thereof, biotin, digoxygenin, gold, ligands, haptens, metals or metal compounds having magnetic properties, and the like. The present invention also provides a kit for the diagnosis of C. pneumoniae infection comprising any of the above mixtures of peptides and manufacturer's instructions for use of said kit. Preferred kits according to the invention are selected from RIA, EIA, ELISA, Immuno competition assays, lateral chromatography assays, and the SeroRapid ® assay. A preferred kit according to the present invention is a kit carrying out an enzyme linked immunoserological assay (ELISA), and said kit comprises said mixture of peptides immobilized on a solid support and the reagents for performing said ELISA. Likewise, the present invention also provides for the use of any of the above mixtures of peptides for the preparation of a diagnostic kit for the detection of C. pneumoniae infection. Furthermore, the present invention also provides for a method for detecting C. pneumoniae infection in an individual comprising: (a) obtaining a body fluid sample from said individual; (b) contacting said body fluid sample with any of the above peptides or mixtures of peptides under suitable assay conditions; and (c) determining the extent of reaction between said body fluid sample and said mixture of peptides. Preferred body fluid samples in accordance with the present invention are serum, saliva, tear fluid, urine, semen, and cervical smears. Especially preferred body fluid samples are bronchiolar lavage and sputum. A preferred method of the present invention is a method comprising performing a diagnostic assay of the ELISA type, wherein said peptides or mixture of peptides are immobilized on a solid support, and then contacted under suitable ELISA conditions with said serum sample and wherein if said serum sample contains antibodies specific for C. pneumoniae MOMP, there will be a detectable positive reaction with said peptides or mixture of peptides. The present invention also provides a conjugate of any one or a mixture of the said peptides with a detectable marker for use in an immunoassay. The present invention also provides the use of any one or a mixture of the said peptides for the preparation of a vaccine. The term "body fluid", as used herein, comprises fluids sampled from within the body, such as blood or lymph, local secretions, such as tears, semen, urine, sweat, sputum etc., samples obtained by washing (e.g. bronchiolar lavage) or swabbing, including cervical smears, and the like. The term "peptide", as used herein, comprises peptides obtained by chemical synthesis, or by cleavage, either by chemical means or by using proteolytic enzymes, of a larger peptide or protein. Other aspects and embodiments of the present invention will be set forth in the following detailed description of the invention or will clearly arise therefrom. Brief Description of the Drawings In the following Figures, the reactivity of the sera to anti-Chlamydia antibodies (positive or negative) was characterized by Microimmunofluorescence, MIF, unless indicated otherwise. Figs. 1-4 are bar graph representations of the results showing the reactivity of various test antigens, i.e., peptides derived from C. trachomatis (C.t.), C. pneumoniae (C.p.), and C. psittacchi (CPIC) MOMP, C. trachomatis elementary bodies (MN), or intact Chlamydia antigen (Int. C.t.) towards various test sera. Fig. 1 shows the specificity of the test antigens towards serum obtained from a positively identified C. trachomatis-infecteά individual, as described in Example 1. Open bars, negative sera, filled bars, positive sera. - Fig. 2 shows the specificity of the test antigens towards serum obtained from a positively identified C. ? eumo.ιiαe-infected individual, as described in Example 1. Open bars, negative sera, filled bars, positive sera. - Fig. 3 shows the specificity of the test antigens, or of the indicated combinations thereof, towards serum obtained from a positively identified C. trachomatis and C. pneumoniae-infected individual, as described in Example 1. Open bars, negative sera, filled bars, positive sera. - Fig. 4 shows the relative sensitivity and antigenicity of the test antigens towards sera obtained from various infected individuals, as described in Example 1. N, Number of sera tested; A, Total number of sera identified positively by MIF; B, total number of sera identified positively by peptide sysytem. - Fig. 5 shows bar graph representations of the reactivity of various new peptides synthesized in accordance with the present invention towards three different sera obtained from three different individuals positively identified as infected with C. trachomatis, as described '" in Example 1. Open bars, negative sera; filled bars, positive sera; O.D., optical density. - Fig. 6 shows bar graph representations of the reactivity of various new peptides synthesized in accordance with the present invention towards three different sera obtained from three different individuals positively identified as infected with C. pneumoniae , as described in Example 1. Open bars, negative sera, filled bars, positive sera, O.D., optical density. - Fig. 7 shows bar graph representations of the reactivity of various new peptides synthesized in accordance with the present invention towards three different sera obtained from three different individuals positively identified as infected with C. trachomatis and C. pneumoniae, as described in Example 1. Open bars, negative sera, filled bars, positive sera, O.D., optical density. - Fig. 8 is a bar graph representation of the relative diagnostic value of each of the newly synthesized peptides according to the present invention towards anti-MOMP antibodies present in test sera, as described in Example 1. Open bars, C.trachomatis-positive sera, filled bars, C.p. -positive sera, %, percent of the total positive (by MIF) sera. C.t., total positive (by peptide system) for C. trachomatis; C.p., total positive (by peptide sysytem) for C. pneumoniae. - Fig. 9 is a bar graph representation of the results showing the specificity and reactivity of mixtures of new peptides of the invention towards serum obtained from positively infected individuals, as described in Example 1. C.t mix, mixture of peptides specific for C. trachomatis; C.p mix, mixture opf peptides specific for C. pneumoniae, hatched bars, C.t positive serum, open bars, negative serum, filled bars, C.p serum, O.D., optical density. - Fig. 10 is a bar graph representation of the sensitivity of the C. pneumoniae peptide-based detection system in comparison to MIF MRL, as described in Example 1. The left-hand, dark bar represents the number of sera characterized by MIF MRL assay as positive; the right-hand, light bar represents the number of sera identified as positive with the C.p peptides system. Detailed Description of the Invention The present invention concerns new peptides and mixtures of peptides derived from the variable domains of the C. pneumoniae MOMP and the use of such peptides in diagnostic kits to detect C. pneumoniae infection in an individual, specifically by detecting the presence of anti- C. pneumoniae MOMP antibodies in test serum samples. The aforesaid peptides or mixtures of peptides have revealed a heretofore not expected high reactivity and specificity towards anti- C. pneumoniae MOMP antibodies and also an essentially very low cross-reactivity with anti-MOMP antibodies of other Chlamydia species. Hence, the present invention also provides a sensitive and specific kit for the diagnosis of C. pneumoniae infection, which kit is based on the above peptides or mixtures of peptides. Preferred kits in accordance with the present invention are those based on ELISA technology as are detailed hereinbelow, and which contain the usual ELISA reagents, or more preferably, various of these reagents which have been improved to provide kits with high sensitivity, long shelf life and ease of use. As regards the various peptides which may be used in accordance with the present invention, the four newly synthesized peptides herein designated C.pNDIII, C.plA, C.p2A, C.p4A have been shown to be preferable for the detection of anti-MOMP antibodies specific to C. pneumoniae in a serum sample. These peptides are suitable for detecting the aforesaid antibodies of the IgA or the IgG type. The specific sequences of these four new peptides have been set forth hereinabove and below. It is to be understood by all of skill in the art that suitable analogs of these new peptides may be readily synthesized by now-standard peptide synthesis methods and apparatus. The only limitation on such analogs is that they have essentially the same high specificity to anti-C. pneumoniae MOMP antibodies and the same very low cross-reactivity with anti-MOMP antibodies of other Chlamydia species. All such analogs will essentially be based on the new peptides as regards their amino acid sequence but will have one or more amino acid residues deleted, substituted or added. When amino acid residues are substituted, such substitutions which are envisaged are those which do not significantly alter the structure or biological activity of the peptide, for example basic amino acids will be replaced with other basic amino acids, acidic ones with acidic ones and neutral ones with neutral ones. When amino acid residues are deleted, the same above restraints are applied as regards obtaining the aforesaid biologically active peptides, and also wherein such deletion analogs will still have between about 10 to about 40 amino acid residues (deletion analogs will usually be no less than about 9 amino acid residues in length). Further, when amino acid residues are added, the aforesaid restraints concerning biological activity are applied and such addition analogs will usually still have between about 10 to about 40 amino acids (addition analogs will usually be up to about 40 amino acids in length). Further, it is to be understood by those of skill in the art, that the use of peptides derived from sequences of the ND of C. pneumoniae MOMP, provided these peptides specifically react with anti-C. pneumoniae antibodies that are formed during the course of an infection with C. pneumoniae, for the purpose of diagnostic detection of antibodies to C. pneumoniae, is within the scope of this invention. For the production of the peptides and the kits containing them '" in accordance with the present invention, well known standard methods of peptide synthesis have been utilized, and the kits are generally based on ones for carrying out assays of the ELISA type and thus contain besides the peptides various other standard ELISA reagents. With each such kit of the invention, detailed instructions are provided for operation of the ELISA procedure as well as various warnings and other precautions necessary. In accordance with the present invention, there are also provided various improved reagents for incorporation into the kits, as mentioned above, and as detailed below. It should be appreciated that the new peptides, and in particular, the new mixtures thereof in accordance with the present invention, may be used in various other forms of diagnostic assays to detect C. pneumoniae infection, the use not being limited only to assays of the ELISA type. Many such assays have been developed, for example, the MIF assays. Likewise, the kits of the present invention may be designed for carrying out diagnostic assays based on these other assay techniques and are hence not limited only to kits for performing such ELISA assays. The present invention will now be described in more detail in the following non-limiting examples and their accompanying figures. Example 1 Development of a mixture of MOMP-derived peptides specific for C. pneumoniae having low cross-reactivity with MOMP from other Chlamydia species As noted above, one aim of the present invention was to develop a peptide- based diagnostic kit that will distinguish serologically between the three Chlamydia species. A series of experiments were carried out for developing the peptide-based ELISA assay, as well as stabilizing the kit. The peptide- based ELISA technology will be described in more detail hereinbelow. The first research step included the synthesis of three species-specific C. pneumoniae (also designated in short hereinbelow as "C.p") peptides and of three Chlamydia trachomatis (also designated in short hereinbelow as "C.t") species-specific peptides. These peptides originated from the four variable domains (VDI-NDIN) of Chlamydia major outer membrane protein (MOMP), Yuan et al., 1989, Melgosa et al., Infect. Immun. 59, 215 (1991). The Sequence of Melgosa et al is deposited as p27455 in the Swissprot database. The database sequence was used as the source for C. pneumoniae MOMP sequence. Three peptides originated from C. pneumoniae MOMP protein, and are designated herein as: A. SEQ. ID NO. 5, herein also designated as C.p VDI, having the sequence: NYTTAVDRPN; B. SEQ. ID NO. 3, herein also designated as C.p VDIII, having the sequence: AFPLPTDAGVATATGTKS; C. SEQ. ID NO. 6, herein also designated as C.p VDIV, having the sequence: SLLGNALSTTDSFSDFMQIV. TA in position 7 of the corresponding sequence of Melgosa et al. was deleted. Three peptides originated from C. trachomatis MOMP protein and are designated herein as: D. SEQ. ID NO. 8, herein also designated as C.t VDI, having the sequence: NAGLENDPTTNVARA; E. SEQ. ID NO. 9, herein also designated as C.t VDII, having the sequence: DNENNATVSDSKLVPNHMSDQS; F. SEQ. ID NO. 10, herein also designated as C.t VDIV, having the sequence: LDNTTNATIAGKGT . The above peptides, as well as all the peptides synthesized and used in accordance with the present invention, were synthesized using standard peptide synthesis methods and apparatus, now well known in the art. The peptides were analyzed by HPLC and had about 80-90% purity, and were formulated as stable lyophilized powders. To determine whether or not these peptides can bind specifically to Chlamydia-infecteά human sera, the present analysis was first focused on calibrating the peptide diagnostic system by an ELISA methodology. It should be noted that the aforesaid ELISA methodology used to calibrate the peptide diagnostic system is a standard well known methodology of which all of skill in the art are aware, and which has been published in many articles, patents and standard texts of the art. More details of this technology where specifically relevant to the present invention are provided in the following examples concerning the kits of the present invention. In another set of experiments, Chlamydia species-specific human sera were tested for their ability, specifically the IgG antibodies in these sera, to bind specifically Chlamydia species-specific peptides using the peptide- based diagnosis system described above. In these experiments, each row of wells of multiwell from the microtiter plates (the solid support) were coated with a different peptide and as a control, one row of wells was coated with intact Chlamydia antigen obtained from Dr. Cavenini, Dept. of Microbiology, University of Bologna, Italy, for known anti-Chlamydia MOMP antibodies. The results of these studies are presented in Figures 1-4, described briefly above. Figure 1, as a specificity control, summarizes the binding pattern (dark bars) of a typical human serum from an individual infected with C. trachomatis. This serum binds to C.t NDIN peptide, but does not bind to the C.p peptides, demonstrating the specificity of the C. pneumoniae- derived peptides. Binding was observed also with the intact C. trachomatis antigen (Int. C.t). Low background binding (open or light bars) was observed, as was determined in the non-infected human serum. In the case of C. pneumoniae infected human serum, the results of which are summarized in Figure 2, part of the infected serum binds specifically to the C.p NDII peptide, and part of it binds specifically to the C.p NDI peptide, although with low reactivity. This shows that MOMP-derived peptides can, in contrast to the prejudice existing in the prior art, react with antibodies formed during C. pneumoniae infection. The intact Chlamydia antigen is fully cross-reactive ("Int. Ct" in Fig. 1 and Fig. 2), highlighting the problematic associated with the prior art technique of using antigens purified from live bacteria as diagnostic tool. It could also be detected in this system sera that reacted specifically with both C. trachomatis peptide and C. pneumoniae peptide, these results being summarized in Figure 3. Figure 4 summarizes the sensitivity of the peptide-based diagnostic system. From 82 Chlamydia-infecteά human sera tested by either the SeroELISA Chlamydia assay or by a standard Microimmunofluorescence methodology (MIF), only 12% reacted with the C. pneumoniae specific peptides. Therefore, the majority of C/ιiαm ycZϊα-positive sera is clearly not recognized by the C. pneumoniae peptides. The above test (SeroELISA Chlamydia) does not distinguish between C. trachomatis and C. pneumoniae. However, since about 50% of the population are C. pneumoniαe-positive, at least 50% of the above sera, which are positive for the genus Chlamydia, are expected to be positive to C. pneumoniae. Therefore, the sensitivity of the C. pneumoniae peptide system is low. To conclude, the above results indicate that the major specific antigens for C. pneumoniae are C.p NDI and C.p NDII, while for C. trachomatis, the major antigen is the C.t NDIN peptide. Lack of sensitivity was observed in the peptide-based diagnostic system, as the majority of C. pneumoniae- infected sera were not detected by this system (data not shown). Also, low C. pneumoniae peptide binding activity was observed. For the purpose of determining cross-reactivity, and also for the purpose of developing a C. trachomatis-specific assay, the following peptides described below were designed. These peptides were derived from C.t NDIN sequences of different C. trachomatis serovars with small modifications, as indicated below. All the peptides share the C. trachomatis C.t NDIN core sequence (marked in italics in the following sequences), yet without any cross-homology to either C. pneumoniae or C. psittaci (as determined by comparing these peptide sequences to the known C. pneumoniae and C. psittaci sequences, these sequences being obtainable, e.g. from the above Melgosa et al., 1991): 1. SEQ. ID NO. 11, IFOXTTLNPTIAGAGOVK - In this peptide, either V (serovars B, Ba) or T (serovars D, E, LI) were deleted in the position that was marked as X. This peptide is designated herein also as C.t.4A. 2. SEQ. ID NO. 12, NDITr NPTZAGCGSVAK - K was added at the C- terminal (originating from F and G serovars). This peptide is also designated herein also as C.t.4B. 3. SEQ. ID NO. 13,CNFDNrT NP7MGAGDVK - To the sequence originating from the L2 serovar, C was added at the Ν-terminal and K was added at the C-terminal. This peptide is also designated herein as C.t.4C. In addition to the above three new modified peptides derived from the C.t NDIN peptide, a fourth peptide being a new modified peptide was also synthesized having a sequence derived from the C.t NDII peptide: 4. SEQ. ID NO. 14, CDNENQSTVKTNSVPNMSLDQSK - Derived from the variable domain II of serovar E. C was added at the N-terminal and K was added at the C-terminal. This peptide is also designated herein as C.t.2A. The above peptides and their use in immunoassay are subject of an Israeli patent application, Attorney's Docket 4195/IL/96, filed on the same day as the present application, and incorporated hereby in its entirety by reference. For the purpose of development of a C. pneumoniae-speci c immunoassay, the following peptides derived from the MOMP protein of C. pneumoniae were designed. These peptides were derived from VD domains of MOMP, but with minimal cross-homology to the MOMP NDs of other chlamydial species (for sequences, see the above Melgosa et al.): 5. SEQ. ID NO. 1, CFSMGAKPTGSAAANYTTANDRPNPAYNK. Derived from the variable domain I, with C added at the N-terminus. This peptide is also designated herein as C.p.lA.. 6. SEQ. ID NO. 2, VKGTTVNANELPNVSLSNGK. Derived from the variable domain II. This peptide is also designated herein as C.p.2A. 7. SEQ. ID NO. 4, LNLTAWNPSLLGNATALSTTDSFK. Derived from the variable domain IV, with K added at the C-terminus. This peptide is also designated herein as C.p.4A. In subsequent experiments, the above new peptides, as well as the aforementioned, previously prepared peptides, were tested using the same test procedure noted above. The tested peptides were: C.t2A, C.t4A, C.t4B, C.t4C, C.plA, C.p2A, C.p4A and C.p.NDIII. Figure 5 summarizes the results of the binding of these peptides to the sera obtained from three distinct C. trachomatis-infected individuals. As is apparent from Figure 5, each serum reacts with different C.t peptide combinations. In all cases, the open bars represent the test reactions in which the peptides were reacted with sera, while the closed (dark) bars represent the control (background) reactions in which negative sera were added to the peptides. Further, all the tested sera were apparently very specific and did not bind any of the C.p peptides, i.e. none of the C.p peptides cross-reacted with any of the sera from C. trachomatis-infected patients. Similar results were observed with C. pneumoniae specific sera, the results of which are summarized in Fig. 6. Also in this case, each serum reacts with different combinations of C. pneumoniae peptides, suggesting that in order to achieve maximum sensitivity, a mixture of peptides should be used. These results suggest that the newly designed C. pneumoniae peptides show high reactivity to sera from patient infected with C. pneumoniae, while at the same time exhibiting low cross-reactivity with sera of patients infected with C. trachomatis. They appear therefore suitable for the development of specific immunoassays, which essentially lack false-positive results when sera are tested for the presence of C. pneumoniae antibodies. Fig. 7 summarizes the binding pattern of three different human sera that were infected with both C. pneumoniae and C. trachomatis. Indeed, each serum interacts with both C. pneumoniae and C. trachomatis peptides, yet with altered peptide combinations, namely, the first (top) reacts with C.t 2A, C.t 4A, C.t 4B, C.t 4C and C.p. 2A, the second (middle) reacts with C.t 2A, C.t 4A, C.t 4C, C.p. 1A and C.p. 2A, and the third (lower) reacts with C.t 4A, C.t 4B, C.t 4C, C.p. 1A, C.p. 2A and C.p.NDIII. The diagnostic value of each peptide (C.plA, C.p2A, C.pNDIII, C.p4A) was determined, the results of which are summarized in Figure 8. Out of 75 C. pneumoniae IgG positive human sera assayed by the C. pneumoniae peptide-based ELISA assay, 33% were positive to C.plA, 60% were positive to C.p2A, 12% were positive to C.pNDIII, and 35% were positive to C.p4A. Since all the C. pneumoniae peptides appear to contribute significantly to the diagnostic value, the reactivity of C. pneumoniae specific sera was tested also on a mixture (1:1:1:1) of four new C. pneumoniae peptides (CplA, C.p 2A, C.p NDIII, C.p 4A) and, as a control, on the four above- noted C. trachomatis peptides (C.t 4A, C.t 4B, C.t 4C, C.t 4D). These results are summarized in Figure 9, from which it is apparent that the mixture of the C.p peptides has a high specific reactivity to C. pneumoniae sera, the cross-reactivity with C. trachomatis sera being very low a id essentially near background levels. The sensitivity of the peptide mixture- based detection system was evaluated by comparison with the MIF MRL kit. As shown in Figure 10, 77% of the sera found positive for C. pneumoniae in the MIF test were also detected by the new peptide-based detection kit. This high sensitivity is likely the result of the use of a peptide mixture, as opposed to the use of single peptides. It was noted that peptide C.p 1A occasionally cross-reacted strongly with sera from C. trachomatis-infected patients. Upon consideration of the literature concerning the various MOMP sequences of different Chlamydia species, it seems that four amino acids near the C-terminus of the peptides, which are identical to the corresponding amino acids of some serovars of C. trachomatis MOMP, may cause the cross-reactivity. Therefore, another peptide was designed, derived from the C.p 1A sequence in which the amino acids PNPAYN were deleted. This peptide has the following sequence: 8. SEQ. ID NO. 7, CFSMGAKPTGSAAANYTTAVDRK, also designated hereinbelow as C.plAimp. C was added at the N-terminus and K was added at the C-terminus. When CplA and CplAimp were compared in their reactivity towards several sera which were confirmed C. trachomatis positive, and towards one serum (#92) which was positive to both C. trachomatis and C. pneumoniae, it was found that CplA reacted with four out of six C. trachomatis-positive sera, as well as with the double-positive serum. CplAimp, on the other hand, only reacted with the double-positive serum (#92), but not or very weak with the other sera (Table 1). Serum F40 was negative to Chlamydia and served as negative control. These results clearly suggest that C.plA contains an epitope which is cross-reactive with anti-C. trachomatis reactivities. Table 1 Specificity of C. pneumoniae peptides The experiments outlined above illustrate the principle of the present invention, namely, that it is possible, by choosing sequences derived from the variable domains of C. pneumoniae MOMP, to design peptides which will react with antibodies formed during infection of an individual with C. pneumoniae. This is contrary to the prejudice of the present state of the art, which teaches that antibody reaction against C. pneumoniae MOMP will be very low or undetectable, as C. pneumoniae MOMP is not recognized by the immune system as an immunodominant protein of the bacteria. In addition, the experiments shown above demonstrate further, that it is possible to obtain, in the way described above, peptides that will specifically react with C. pneumoniae, and further, where such peptides are only partially specific, it is possible to improve their specificity by deleting amino acid sequences that are cross-homologous to other Chlamydia species. Also the obtention of species-specific reactivities in peptides derived from C. pneumoniae MOMP is contrary to the prejudice of the prior art, which teaches that C. pneumoniae MOMP contains genus- rather than species- specific epitopes. When employing the above mixture of peptides in an ELISA assay on a large number of sera which had been confirmed by MIF MRL assay to be reactive against C. pneumoniae, it was found that the peptide-based assay detected 77% of all C. pneumoniae-positive sera (Figure 8). Considering the fact that the MIF assays are to some extent cross-reactive, and that the extent of cross-reactivity depends upon the skill of the interpretation of the test results, it seems likely that some of the sera which tested positive in MIF assay in Table 1, were in fact not positive for C. pneumoniae. The peptide-based system, on the other hand, is likely, through its use of chemically synthesized and hence pure antigen, to avoid cross-reactivity, to a larger degree than the detection systems of the prior art that are based upon the use of whole bacteria of components thereof. Therefore, a peptide-based system for the detection of anti-Chlamydia pneumoniae antibodies in a patient is highly sensitive and specific, while at the same time easy to use and cost-effective. Example 2 Conditions that enhance stability of immobilized peptides for long-term storage In view of the use of the peptide mixture described herein for the development of a diagnostic kit it is essential to check the immobilized peptides for stability, as they are, e.g. in the form of peptide-coated microtiter plates, to be provided as components of a kit. By employing accelerated stability tests, i.e. storing the immobilized peptides at 37°C and comparing the test results with results obtained from peptides stored at 4°C, it has been found that the composition of the buffer employed for blocking after adsorption of the peptides is critical. In particular, this buffer should not, in contrast to the ELISA method as known in the art, contain Tween-20. Also, the addition of 1-20% sucrose, preferably 10% sucrose, was found to further enhance stability of the peptides for storage. As will be detailed below, the different peptides exhibit various degrees of instability, but all peptides can be stored stably when the sucrose- containing blocking buffer is used. As will be apparent to the skilled artisan when taking into account the necessity to use different peptides in order to achieve species-specificity as detailed in Example 1, such a buffer formulation is extremely useful when developing diagnostic kits based on peptides. The use of such buffer also stabilizes peptides derived from other sequences, as detailed below, namely, the C. pneumoniae MOMP NDI, NDII and NDIN. The use of such buffer for the purpose of carrying out an immunoassay with immobilized peptides is the subject of a copending application by the same applicants, filed on the same day as the present application, Attorney's docket 4326/97. In order to test the influence of sucrose and Tween in the blocking solution on the stability of various peptides, four peptides derived from C. trachomatis and four peptides as well as a mixture of these derived from C. pneumoniae were tested independently. Testing was carried out by incubation of the immobilized peptides at 37°C for three to ten days and comparing the results to peptides which were incubated at 4°C. The following Tables show on the right side ELISA results obtained with peptides incubated at the indicated temperatures and for the indicated times, while at the right side they give the ratio of the results obtained at 37°C incubation versus the results obtained by 4°C incubation. A ratio of about 1 or greater indicates that the peptide is stable when incubated at 37°C, while smaller ratios (<0.9) indicate instability of the immobilized peptide. A) Results obtained using C. trachomatis peptides Tables 2-13 show the results of ELISA essays carried out with immobilized peptides stored dry when coated on ELISA plates for the indicated times and at the indicated temperatures. The assay was carried out as described for Table 1, with 10% sucrose and/or 0.05% Tween-20 added to the blocking buffer where indicated. All of the tested C. trachomatis peptides were essentially stable when blocking buffer containing sucrose was used (see Tables 2, 5, 8, 11). When sucrose was omitted from the blocking buffer, a significant decrease in reactivity to most sera was observed for peptide Ct4A and Ct4C (Tables 3 and 9), a decrease to three of the sera for Ct4B (Table 6), and a slight decrease to four sera for Ct4D (Table 12). These data show clearly that each peptide displays several epitopes, and that the reactivity of these epitopes to the antisera is influenced differentially storage of the dried immobilized peptides, but that all epitopes can be preserved when sucrose- containing buffer is used for blocking. When sucrose was omitted from the blocking solution and Tween-20 was added (as is customary in ELISA procedures), the stability of some of the peptides was decreased by much, e.g. Ct4A (compare Table 4 to Table 3), and Ct4B (compare Table 7 to Table 5), while the other two peptides were less affected, but still exhibited slightly lower reactivities when Tween-20 was present in the blocking buffer (compare Table 10 to Table 9 and Table 13 to Table 12). Table 2 peptide Ct4A, blocker with sucrose 37°C/4°C serum 4°C 3 dav 7 day 10 day 3 day 7 day 10 day - H 156 1.246 1.437 1.277 1.333 1.153 1.024 1.069 H 171 0.719 0.791 0.709 0.742 1.100 0.985 1.032 H 130 0.627 0.679 0.635 0.558 1.083 1.014 0.890 H 186 0.687 0.712 0.678 0.689 1.036 0.987 1.003 H 203 0.820 0.822 0.862 0.740 1.002 1.051 0.902 M92+H 163 0.767 0.737 0.825 0.745 0.962 1.076 0.971 F 111 0.483 0.495 0.466 0.477 1.025 0.965 0.989 F 210 0.402 0.302 0.245 0.328 0.752 0.609 0.816 Table 3 peptide Ct4A, blocker without sucrose with PBS. 37°C/4°C serum 4°C 3 day 7 day 10 day 3 day_ 7 day 10 day H 156 1.3270 1.1570 0.9535 0.9165 0.8719 0.7185 0.6907 H 171 0.7035 0.6360 0.5885 0.5380 0.9041 0.8365 0.7647 H 130 0.5760 0.4945 0.4295 0.3920 0.8585 0.7457 0.6806 H 186 0.7430 0.6035 0.5590 0.5435 0.8122 0.7524 0.7315 H 203 0.7945 0.6310 0.5980 0.5640 0.7942 0.7527 0.7099 M92+H 163 0.7225 0.5700 0.5420 0.5335 0.7889 0.7502 0.7384 F 111 0.4515 0.5630 0.4790 0.4755 1.2470 1.0609 1.0532 F 210 0.4145 0.3780 0.4045 0.3950 0.9119 0.9759 0.9530 Table 4 peptide Ct4A, blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 day 7 day 10 day 3 day 7 day 10 day H 156 1.304 0.800 0.758 0.698 0.613 0.581 0.535 H 171 0.669 0.515 0.494 0.447 0.770 0.739 0.668 H 130 0.561 0.324 0.316 0.275 0.577 0.563 0.490 H 186 0.719 0.530 0.504 0.451 0.736 0.701 0.627 H 203 0.762 0.493 0.439 0.371 0.647 0.576 0.487 92+H 163 0.657 0.454 0.427 0.374 0.691 0.650 0.569 F 111 0.422 0.302 0.441 0.382 0.716 1.045 0.905 F 210 0.377 0.306 0.271 0.296 0.813 0.720 0.786 Table 5 peptide Ct4B, blocker with sucrose 37°C/4°C serum 4°C 3 day 7 day 10 day 3 day 7 day 10 day H 156 0.298 0.321 0.319 0.330 1.077 1.072 1.109 H 171 0.481 0.481 0.496 0.483 1.000 1.031 1.004 H 130 0.673 0.683 0.659 0.599 1.015 0.979 0.890 H 186 0.642 0.623 0.609 0.567 0.971 0.949 0.884 H 203 0.526 0.528 0.538 0.507 1.004 1.022 0.963 M92+H 163 0.308 0.291 0.278 0.262 0.946 0.902 0.852 F 111 0.218 0.265 0.258 0.254 1.213 1.181 1.163 F 210 0.266 0.260 0.260 0.276 0.979 0.979 1.040 Table 6 peptide Ct4B, blocker without sucrose with PBS. 37°C/4°C serum 4°C 3 day 7 day 10 day 3 day 7 day 10 day H 156 0.267 0.254 0.248 0.279 0.953 0.931 1.047 H 171 0.425 0.350 0.360 0.340 0.823 0.848 0.801 H 130 0.623 0.499 0.450 0.431 0.801 0.722 0.691 H 186 0.566 0.463 0.440 0.371 0.818 0.778 0.655 H 203 0.483 0.405 0.368 0.322 0.839 0.761 0.667 M92+H 163 0.279 0.301 0.266 0.296 1.079 0.953 1.061 F 111 0.273 0.257 0.243 0.271 0.943 0.892 0.994 F 210 0.255 0.226 0.260 0.278 0.888 1.020 1.092 Table 7 peptide Ct4B, blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 day 7 day 10 day 3 day 7 day 10 day H 156 0.300 0.268 0.267 0.283 0.892 0.888 0.943 H 171 0.464 0.353 0.352 0.335 0.760 0.759 0.721 H 130 0.628 0.435 0.402 0.369 0.693 0.640 0.588 H 186 0.679 0.481 0.438 0.401 0.708 0.645 0.591 H 203 0.566 0.386 0.319 0.299 0.683 0.563 0.528 M92+H 163 0.285 0.289 0.277 0.271 1.016 0.972 0.951 F 111 0.253 0.243 0.251 0.254 0.960 0.990 1.002 F 210 0.427 0.241 0.245 0.275 0.564 0.574 0.643 Table 8 peptide Ct4C, blocke r with sucrose 37°C/4°C serum 4°C 3 day 7 dav 10 dav ref (605) 3 dav 7 dav 10 dav H 156 1.952 1.831 1.814 1.825 1.530 0.938 0.929 0.935 H 171 0.739 0.694 0.696 0.691 0.436 0.940 0.942 0.935 H 130 0.742 0.675 0.663 0.675 0.821 0.910 0.893 0.910 H 186 0.944 0.940 0.982 0.965 0.781 0.996 1.040 1.022 H 203 0.995 0.968 1.049 1.055 0.806 0.972 1.054 1.060 M92+H16 2.100 1.911 2.018 1.954 1.051 0.910 0.961 0.930 F 111 0.281 0.258 0.251 0.255 0.214 0.918 0.891 0.906 F 210 0.302 0.278 0.299 0.289 0.223 0.919 0.988 0.955 Table 9 peptide Ct4C, blocker without sucrose with PBS. 37°C/4°C serum 4°C 3 dav 7 dav 10 dav ref (605) 3 day 7 dav 10 dav H 156 1.854 1.620 1.551 1.365 1.613 0.874 0.837 0.736 H 171 0.708 0.617 0.591 0.504 0.444 0.872 0.835 0.712 H 130 0.671 0.544 0.466 0.443 0.857 0.811 0.694 0.659 H 186 0.946 0.863 0.754 0.749 0.790 0.912 0.797 0.791 H 203 1.018 0.796 0.751 0.689 0.875 0.781 0.737 0.677 M92+H16 2.099 1.776 1.581 1.390 1.342 0.846 0.753 0.662 F 111 0.451 0.265 0.283 0.293 0.226 0.588 0.626 0.650 F 210 0.271 0.309 0.339 0.296 0.226 1.140 1.249 1.092 Table 10 peptide Ct4C, blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 dav 7 dav 10 dav ref (605) 3 dav 7 dav 10 dav H 156 1.879 1.370 1.310 1.221 1.571 0.729 0.697 0.650 H 171 0.713 0.563 0.592 0.538 0.458 0.789 0.830 0.755 H 130 0.633 0.407 0.389 0.421 0.805 0.643 0.615 0.666 H 186 0.983 0.794 0.713 0.720 0.803 0.808 0.726 0.733 H 203 1.062 0.751 0.749 0.703 0.871 0.707 0.705 0.662 M92+H16 1.568 1.017 0.831 0.747 1.141 0.649 0.530 0.477 F 111 0.276 0.306 0.261 0.252 0.244 1.107 0.946 0.913 F 210 0.682 0.290 0.290 0.320 0.233 0.426 0.425 0.470 Table 11 peptide Ct4D, blocker with sucrose 37°C/4°C serum 4°C 3 dav 7 dav 10 dav ref (605) 3 day 7 dav 10 dav H 156 0.568 0.618 0.520 0.577 1.530 1.088 0.915 1.016 " H 171 0.542 0.543 0.536 0.544 0.429 . 1.003 0.989 1.004 H 130 0.439 0.406 0.403 0.391 0.802 0.926 0.919 0.891 H 186 0.712 0.726 0.726 0.713 0.769 1.019 1.020 1.001 H 203 0.292 0.285 0.267 0.280 0.766 0.974 0.913 0.959 M92+H16 0.372 0.351 0.368 0.345 1.248 0.943 0.991 0.927 F 111 0.366 0.327 0.309 0.318 0.210 0.893 0.843 0.867 F 210 0.352 0.333 0.322 0.335 0.221 0.945 0.915 0.950 Table 12 peptide Ct4D, blocker without sucrose with PBS. 37°C/4°C serum 4°C 3 dav 7 dav 10 dav 3 day 7 dav 10 dav H 156 0.546 0.478 0.490 0.458 0.875 0.897 0.838 H 171 0.570 0.504 0.506 0.458 0.883 0.887 0.804 H 130 0.407 0.343 0.320 0.324 0.842 0.786 0.795 H 186 0.736 0.639 0.572 0.680 0.868 0.777 0.923 H 203 0.315 0.257 0.312 0.276 0.816 0.992 0.876 M92+H16 0.361 0.326 0.360 0.345 0.903 0.999 0.956 F 111 0.309 0.315 0.324 0.315 1.018 1.047 1.019 F 210 0.307 0.307 0.319 0.333 1.000 1.039 1.083 Table 13 peptide Ct4D, blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 dav 7 day 10 dav 3 dav 7 dav 10 dav H 156 0.495 0.364 0.365 0.358 0.736 0.737 0.724 H 171 0.510 0.425 0.447 0.410 0.834 0.877 0.805 H 130 0.309 0.236 0.259 0.266 0.765 0.838 0.861 H 186 0.751 0.647 0.573 0.508 0.861 0.763 0.676 H 203 0.225 0.194 0.200 0.185 0.860 0.887 0.822 M92+H16 0.337 0.323 0.336 0.603 0.957 0.996 1.789 F 111 0.267 0.272 0.272 0.280 1.019 1.019 1.051 F 210 0.282 0.292 0.290 0.293 1.037 1.028 1.041 B) Results obtained using C. pneumoniae peptides In order to find out whether the presence of sucrose in the blocking buffer only affects C. trachomatis peptides (all of the tested peptides were from the NDIN region of the MOMP protein and therefore homologous in their sequence), or also affects the stability of other peptides, various peptides derived from the MOMP protein sequence of C. pneumoniae were tested for stability as described above for C. trachomatis peptides. When sucrose was present in the blocking buffer, peptides C.pNDIII, C.plA were essentially stable (see Tables 14, 20). Also a mixture of peptides (C.plA, C.p2A, C.pNDIII. C.p4A), was stable (Table 17). When sucrose was omitted from the blocking solution, however, the stability of the reactivity of the peptides was reduced for two sera in the case of C.p NDIII (Table 15), for five sera in the case of the peptide mixture (Table 18), and for four sera in the case of C.p 1A (Table 21). The slight instability of peptide C.p 2A observed with sucrose-containing buffer (Table 23, ratios between 0.8 and 0.9 for M92, H171+H226, H171 and H156) was significantly increased when sucrose was omitted from the buffer (Table 24, ratios between 0.5 and 0.8 for the same sera). The addition of Tween-20 to the blocking solution as customary in the art of ELISA further reduced the stability of the C. pneumoniae peptides, as can be seen for C.p NDIII (compare Table 16 to Table 15), and the peptide mixture (compare Table 19 to Table 18). On the other hand, the stability of C.plA was unaffected by the presence of Tween in the blocking buffer (compare Table 22 to Table 21), while Tween even seemed to have a beneficial effect on the stability of C.p 2A (compare Table 25 to Table 24, sera M92 and H163). However, even in the case of C.p 2A, the addition of sucrose was superior to the addition of Tween with regard to enhanced stability (compare e.g. sera M95 and H163 in Tables 23-25). In summary, the above experiments suggest that the C. trachomatis and C. pneumoniae peptides used herein display several epitopes, that these epitopes are independently affected by storage without sucrose and by the addition of Tween into the blocking solution. They further suggest that storage without sucrose may lead to the exposure or formation of epitopes that bind unspecifically, giving rise to high background levels and therefore raising the likelihood to obtain a false-positive output in the assay. In very rare cases, the addition of Tween-20 may help to stabilize a specific epitope, as in the case of reactivity of Cp2A to H163 (compare Tables 31 and 30). The omission of Tween-20 and the addition of sucrose to the blocking buffer, which is in contrast to the current teaching in the art of ELISA, overcome all these problems. This is demonstrated using a variety of peptides that are derived from different areas (VDl, NDII and NDIN) of the MOMP of two different Chlamydia strains. The peptides therefore have no common structure or sequence homology, so that the results obtained here are likely to be valid for peptides in general. Table 14 C.p VDIII, blocker with sucrose 37°C/4°C serum 4°C 3 dav 1 week 10 day 3 day 1 week 10 day ' M 92 0.488 0.462 0.448 0.482 0.946 0.917 0.988 H171+H228 0.497 0.534 0.476 0.479 1.074 0.958 0.963 H 228 0.448 0.476 0.414 0.415 1.061 0.923 0.926 H 163 0.720 0.672 0.692 0.692 0.933 0.962 0.961 H 171 0.488 0.511 0.490 0.494 1.047 1.003 1.011 H 247 0.590 0.553 0.537 0.542 0.938 0.910 0.919 H 156 0.371 0.356 0.366 0.368 0.960 0.985 0.991 H 203 0.185 0.186 0.188 0.223 1.005 1.019 1.206 Table 15 C.p VDIII , blocker without sucrose with PBS 37°C/4°C serum 4°C 3 day 1 week 10 day 3 day 1 week 10 day M 92 0.499 0.409 0.434 0.409 0.819 0.870 0.820 H171+H228 0.477 0.641 0.425 0.436 1.343 0.891 0.914 H 228 0.461 0.421 0.485 0.537 0.913 1.052 1.166 H 163 0.753 0.768 0.581 0.590 1.019 0.771 0.783 H 171 0.480 0.437 0.448 0.455 0.910 0.934 0.948 H 247 0.597 0.555 0.553 0.605 0.929 0.926 1.013 H 156 0.357 0.352 0.335 0.366 0.986 0.938 1.025 H 203 0.191 0.199 0.213 0.288 1.039 1.115 1.505 Table 16 C.p VDIII , blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 day 1 week 10 day 3 day 1 week 10 day M 92 0.545 0.413 0.416 0.406 0.758 0.763 0.744 H171+H228 0.495 0.415 0.405 0.422 0.837 0.817 0.852 H 228 0.462 0.427 0.454 0.493 0.925 0.983 1.067 H 163 0.749 0.607 0.579 0.591 0.810 0.774 0.790 H 171 0.636 0.416 0.420 0.414 0.654 0.661 0.651 H 247 0.585 0.558 0.514 0.538 0.954 0.879 0.920 H 156 0.328 0.313 0.322 0.326 0.953 0.980 0.994 H 203 0.200 0.215 0.200 0.228 1.075 1.000 1.138 Table 17 CP MIX , blocker with sucrose 37°C/4°C serum 4°C 3 dav 1 week 10 day 3 dav 1 week 10 dav M 92 2.528 2.452 2.486 2.498 0.970 0.983 0.988 H171+H228 0.445 0.521 0.568 0.517 1.172 1.277 1.163 H 228 2.126 2.136 2.075 2.190 1.005 0.976 1.030 H 163 1.180 1.172 1.192 1.210 0.994 1.010 1.026 H 171 0.712 0.746 0.721 0.745 1.048 1.013 1.046 H 247 0.721 0.710 0.734 0.735 0.984 1.017 1.019 H 156 0.249 0.272 0.271 0.235 1.093 1.089 0.944 H 203 0.137 0.157 0.138 0.143 1.147 1.007 1.044 Table 18 CP MIX , blocker without sucrose with PBS. 37°C/4°C serum 4°C 3 dav 1 week 10 dav 3 day 1 week 10 dav M 92 2.65 2.33 1.72 1.96 0.88 0.65 0.74 H171+H228 0.55 0.41 0.38 0.52 0.75 0.69 0.94 H 228 2.09 1.84 1.76 1.70 0.88 0.84 0.82 H 163 1.17 0.93 0.87 0.88 0.79 0.74 0.75 H 171 0.63 0.49 0.43 0.45 0.78 0.68 0.71 H 247 0.71 0.57 0.51 0.52 0.81 0.72 0.73 H 156 0.23 0.22 0.24 0.25 0.96 1.01 1.05 H 203 0.16 0.16 0.17 0.19 1.00 1.02 1.19 Table 19 CP MIX , blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 dav 1 week 10 dav 3 day 1 week 10 day M 92 2.601 1.734 1.448 1.262 0.667 0.557 0.485 H171+H228 0.668 0.431 0.386 0.424 0.644 0.577 0.635 H 228 2.071 1.754 1.475 1.446 0.847 0.712 0.698 H 163 1.094 0.831 0.734 0.703 0.760 0.671 0.643 H 171 0.711 0.558 0.439 0.578 0.785 0.617 0.813 H 247 0.684 0.459 0.466 0.417 0.671 0.682 0.610 H 156 0.257 0.276 0.267 0.243 1.074 1.041 0.945 H 203 0.148 0.166 0.165 0.172 1.122 1.119 1.163 Table 20 C.plA, blocker with sucrose 37°C/4°C serum 4°C 3 dav 1 week 10 dav 3 day 1 week 10 dav - M 92 1.830 1.749 1.732 1.729 0.955 0.946 0.945 H171+H226 0.875 0.885 0.803 0.837 1.011 0.918 0.957 H 228 2.272 2.278 2.233 2.243 1.003 0.983 0.987 H 163 1.300 1.315 1.295 1.320 1.012 0.996 1.015 H 171 0.471 0.484 0.575 0.472 1.029 1.222 1.003 H 247 0.658 0.669 0.681 0.635 1.017 1.035 0.965 H 156 0.591 0.552 0.573 0.548 0.935 0.970 0.928 H 203 0.242 0.299 0.269 0.276 1.236 1.112 1.140 Table 21 C.p 1A, blocker without sucrose with PBS. 37°C/4°C serum 4°C 3 dav 1 week 10 dav 3 day 1 week 10 dav M 92 1.593 1.143 0.865 0.798 0.717 0.543 0.501 H171+H226 0.719 0.603 0.529 0.554 0.839 0.736 0.770 H 228 2.119 1.771 1.407 1.421 0.836 0.664 0.671 H 163 1.146 0.980 0.831 0.753 0.855 0.725 0.657 H 171 0.429 0.475 0.474 0.399 1.106 1.105 0.929 H 247 0.623 0.544 0.566 0.547 0.872 0.908 0.877 H 156 0.465 0.450 0.460 0.445 0.968 0.990 0.957 H 203 0.253 0.245 0.214 0.234 0.966 0.844 0.923 Table 22 C.p 1A, blocker without sucrose with PBS-T. 37°C/4°C serum 4°C 3 day 1 week 10 day 3 day. 1 week 10 day M 92 1.574 0.878 0.813 0.737 0.558 0.517 0.468 H171+H226 0.803 0.628 0.776 0.693 0.783 0.967 0.863 H 228 2.129 1.681 1.554 1.466 0.790 0.730 0.689 H 163 1.145 0.892 0.811 0.748 0.779 0.708 0.653 H 171 0.395 0.476 0.423 0.467 1.204 1.070 1.181 H 247 0.594 0.520 0.478 0.579 0.875 0.805 0.975 H 156 0.524 0.430 0.467 0.471 0.820 0.890 0.898 H 203 0.231 0.336 0.291 0.268 1.458 1.262 1.163 Table 23 C.p 2A, blocker with sucrose 37°C/4°C serum 4c 3 dav 1 week 10 day 3 day 1 week 10 dav - M 92 2.703 2.539 2.307 2.151 0.939 0.853 0 7956 H171+H226 0.815 0.786 0.842 0.714 0.964 1.033 0.8761 H 228 0.686 0.644 0.627 0.638 0.939 0.914 0.9300 H 163 0.550 0.672 0.582 0.677 1.221 1.058 1.2309 H 171 1.062 1.108 0.899 0.888 1.043 0.847 0.8357 H 247 0.608 0.535 0.507 0.522 0.880 0.833 0.8586 H 156 0.487 0.480 0.448 0.497 0.986 0.920 1.0205 H 203 0.247 0.415 0.264 0.241 1.678 1.067 0.9757 Table 24 C.p 2A, blocker without sucrose with PBS. 37°C/4°C serum 4c 3 day 1 week 10 dav 3 day 1 week 10 day M 92 2.518 1.927 1.548 1.477 0.765 0.615 0.587 H171+H226 0.714 0.576 0.598 0.528 0.807 0.837 0.740 H 228 0.585 0.504 0.487 0.561 0.862 0.833 0.959 H 163 0.503 0.461 0.409 0.371 0.916 0.813 0.738 H 171 0.875 0.785 0.722 0.636 0.897 0.825 0.727 H 247 0.498 0.487 0.490 0.490 0.978 0.984 0.985 H 156 0.360 0.378 0.371 0.367 1.050 1.031 1.021 H 203 0.176 0.182 0.186 0.192 1.034 1.054 1.091 Table 25 C.p 2A, blocker without sucrose with PBS-T 37°C/4°C serum 4c 3 dav 1 week 10 day 3 day 1 week 10 dav M 92 2.606 1.852 1.703 1.692 0.711 0.654 0.649 H1 1+H226 0.729 0.551 0.521 0.520 0.756 0.714 0.714 H 228 0.634 0.525 0.764 0.514 0.828 1.205 0.810 H 163 0.470 0.502 0.355 0.503 1.067 0.754 1.070 H 171 0.943 0.792 0.659 0.646 0.840 0.699 0.685 H 247 0.503 0.414 0.402 0.437 0.824 0.800 0.870 H 156 0.350 0.318 0.290 0.316 0.910 0.830 0.903 H 203 0.173 0.354 0.185 0.172 2.049 1.070 0.994 Example 2 Development and Characterization of a Diagnostic Kit Specific for C. pneumoniae The diagnostic kits developed in accordance with the present invention are essentially improved Enzyme-Linked Immunosorbent Assay (ELISA) kits designed specifically for the diagnosis of C. pneumoniae-speciHc infections. Two basic kits have been developed, both being manipulatable to vary various of the constituents thereof to meet the users' needs. One kit is intended for the determination of specific C. pneumoniae IgG antibodies in human sera, this being designated herein as the "IgG kit". The second kit is intended for the determination of specific C. pneumoniae IgA antibodies in human sera, this being designated herein as the "IgA kit". Generally, the above kits of the invention will have at least some of the following constituents: (i) A C. pneumoniae antigen-coated microtiter plate with a plate cover, usually of the standard multiwell type having 96 wells per plate arranged in the form of 12 columns and 8 rows, i.e., 8 wells per column for a total of 96 wells. With such plates, there will be provided 12 removable 8-well strips coated with the C. pneumoniae antigen. The C. pneumoniae antigen will preferably be a mixture of new peptides as set forth in Example 1 above, the most preferred mixtures being those designated in Example 1 as "Cp mix 1" and "Cp mix 2". Hence, for each well of the microtiter plate, there will be a strip coated with the C. pneumoniae peptide mixture of the invention. (ii) A concentrated wash buffer, usually being a concentrated PBS- Tween buffer of the standard type well known in the art. (iii) A serum diluent, usually in the form of a ready-to-use colored buffer solution. (iv) A conjugate diluent, usually in the form of a ready-to-use " colored buffer solution. (v) A negative control which is usually a C. pneumoniae IgG or IgA negative human serum in a ready-to-use form. (vi) A positive control which is usually a C. pneumoniae IgG or IgA positive human serum in a ready-to-use form. (vii) A concentrated HRP-conjugate, usually in the form of horseradish peroxidase (HRP) conjugated to anti-human IgG or anti-human IgA (gamma chain specific). (viii) A concentrated TMB-substrate, usually in the form of 3, 3', 5,5'- tetramethyl-benzidine (TMB) in dimethylsulfoxide (DMSO) as chromagen and urea hydrogen peroxide as substrate for peroxidase (HRP). (ix) A stop solution, usually containing 1 M H 2 SO in a ready-to-use form. (x) Detailed instructions for use, inclusive of warnings and precautions. Of all of the above constituents, those unique to the present invention, and hence essential to the kits of the invention, are: (i) the C. pneumoniae peptide mixture-coated microtiter plate, and (x) the detailed instructions for use. All the other constituents, (ii)-(ix) may be the improved or modified ones noted below in accordance with the invention, or standard, commercially available equivalents well known in the art of ELISA. Using the above kits and new mixtures of C. pneumoniae peptides, the basic assay procedure is as follows: Assay Procedure 1. Incubation of the sera samples and controls: 1.1 Dilute each patient serum 1/10 or 1/21 with the serum diluent (commercially available and usually supplied with the kit; see also below). 1.2 Pipette 50 μl from positive control, negative control and from the diluted patient serum (from step 1.1) into separate wells of the test strip (as noted above, each strip is an antigen-coated 8-well strip, with a possibility of 12 such strips per microtiter plate when using 96-well plates). 1.3 Cover the strips (i.e., cover the whole plate with the plate cover) and incubate for 1 hour at 37°C in a humidified environment. 1.4 Discard the liquid contents of the wells. 1.5 Washing step: Fill each well with wash buffer and discard the liquid; repeat this step six times. 1.6 Dry the strips and ELISA plate, gently tapping them over clean absorbent paper. 2. Incubation with conjugate: 2.1 Dilute the concentrated (usually 300x concentrated) HRP conjugate anti-human IgG 1/300 with conjugate diluent. 2.2 Pipette 50 μl of diluted conjugate into each well. 2.3 Cover the strips and incubate for one hour at 37°C in a humidified environment. 2.4 Discard the liquid content and wash as described in step 1.5. 2.5 Dry the strips and ELISA plate by gently tapping them over clean absorbent paper. 3. Incubation with TMB substrate: 3.1 Dilute the concentrated (usually lOx concentrated) TMB-Substrate 1/10 in DDW. Alternatively, ready-to-use (RTU)-TMB substrate may be used, and the dilution step omitted. 3.2 Pipette lOOμl of diluted TMB-Substrate into each well, cover the strips and incubate at room temperature for 10 minutes only. Alternatively, the RTU-TMB substrate may be used, and incubation extended to 15 minutes. 3.3 Stop the reaction by adding 100 μl of IM H 2 SO (chromogen stop solution) to each well. 3.4 Determine the absorbence at 450 nm and record the results. b) Development of improved serological diagnostic kits: The following is an outline of the development of the improved kits: 1) Making the kits more "user friendly": a. Reducing the number of washing steps. b. Adding different colors to the serum diluent and the conjugate diluent. c. Stabilizing the kit for longer shelf life. 2) Clinical evaluations of the improved kits. In order to achieve goal la) above, namely, to reduce the number of washing steps from six to three, different wash buffers were tested and compared to the original one usually used in ELISA, which is a PBS-based buffer. These wash buffers contained an increasing amount of non-ionic detergents, or ionic detergents. Results: The wash buffer that enabled only three washing steps was the one that contained non-ionic detergent, this being the above-noted PBS- Tween buffer (see constituent no. (ii) in the above list). Further, it was found that this PBS-Tween buffer could be readily prepared in a preferred concentration of 20x concentrated, which 20x concentrated wash buffer was stable for one month at 37°C and for 11 months at 4°C. To achieve the goal set forth in lb) above, the following was carried out: The following colors were added either to the serum diluent or to the conjugate diluent and tested: violet powder, evans blue, mocca brown powders and from the food colors: blue brilliant, yellow sunset and their combination (green color). Results: The violet, evans blue and mocca brown colors had some interference with the test, by either increasing the background signal and/or decreasing the actual test signal. The only colors that worked well in the test were the blue brilliant, yellow sunset and their combination (green color). It should also be noted that the blue brilliant and yellow sunset colors and their combination (green color) were stable for one month at 37°C and for one year at 4°C. Based on these results, in the preferred kits of the invention, the serum diluent is provided with blue color and the conjugate diluent is provided with green color, thereby providing for optimal distinction between the two diluents on a color basis, while at the same time, these colors do not interfere with the assay. Regarding the goal of lc above, it was found that RTU-TMB substrate was stable for one month at 37 °C and for 12 months at 4°C. This is also the case for the other reagents used in the improved kit, as mentioned above. It should be mentioned, as indicated above, that the development of the IgA C. pneumoniae specific kit was performed in the same way as described hereinabove for the IgG C. pneumoniae specific kit. The following Table 26 provides an outline for evaluating the results and interpreting them when testing sera with both the IgG and IgA kits: Table 26 Significance of results based on the combination of IgA and IgG antibodies, as obtained using both IgG and IgA kits to test each serum sample SEQUENCE LISTING (1) GENERAL INFORMATION: (i) APPLICANT: (A) NAME: Savyon Diagnostics Ltd. (B) STREET: Kiryat Minrav, 3 Habosem Str. (C) CITY: Ashdod (E) COUNTRY: Israel (F) POSTAL CODE (ZIP) : 77101 (G) TELEPHONE: +972 8 856 2920 (H) TELEFAX: +972 8 856 3258 (ii) TITLE OF INVENTION: C. pneumoniae Specific Peptides and their Use in Immunoassays (iii) NUMBER OF SEQUENCES: 14 (iv) COMPUTER READABLE FORM: (A) MEDIUM TYPE: Floppy disk (B) COMPUTER: IBM PC compatible (C) OPERATING SYSTEM: PC-DOS/MS-DOS (D) SOFTWARE: Patentln Release #1.0, Version #1.30 (EPO) (2) INFORMATION FOR SEQ ID NO: 1: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 29 amino acids (B) TYPE: amino acid (C) STRANDEDNESS : single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 1: Cys Phe Ser Met Gly Ala Lys Pro Thr Gly Ser Ala Ala Ala Asn Tyr 1 5 10 15 Thr Thr Ala Val Asp Arg Pro Asn Pro Ala Tyr Asn Lys 20 25 (2) INFORMATION FOR SEQ ID NO: 2: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 20 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 2: Val Lys Gly Thr Thr Val Asn Ala Asn Glu Leu Pro Asn Val Ser Leu 1 5 10 15 Ser Asn Gly Lys 20 (2) INFORMATION FOR SEQ ID NO: 3: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 18 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 3: Ala Phe Pro Leu Pro Thr Asp Ala Gly Val Ala Thr Ala Thr Gly Thr 1 5 10 15 Lys Ser [ 2 ) INFORMATION FOR SEQ ID NO: 4: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 24 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 4: Leu Asn Leu Thr Ala Trp Asn Pro Ser Leu Leu Gly Asn Ala Thr Ala 1 5 10 15 Leu Ser Thr Thr Asp Ser Phe Lys 20 (2) INFORMATION FOR SEQ ID NO: 5: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 10 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 5: Asn Tyr Thr Thr Ala Val Asp Arg Pro Asn 1 5 10 (2) INFORMATION FOR SEQ ID NO: 6: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 20 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 6: Ser Leu Leu Gly Asn Ala Leu Ser Thr Thr Asp Ser Phe Ser Asp Phe 1 5 10 15 Met Gin He Val 20 (2) INFORMATION FOR SEQ ID NO: 7: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 23 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 7: Cys Phe Ser Met Gly Ala Lys Pro Thr Gly Ser Ala Ala Ala Asn Tyr 1 5 10 15 Thr Thr Ala Val Asp Arg Lys 20 (2) INFORMATION FOR SEQ ID NO: 8: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 15 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 8 : Val Ala Gly Leu Glu Asn Asp Pro Thr Thr Asn Val Ala Arg Ala 1 5 10 15 (2) INFORMATION FOR SEQ ID NO: 9: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 22 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 9: Asp Asn Glu Asn Asn Ala Thr Val Ser Asp Ser Lys Leu Val Pro Asn 1 5 10 15 His Met Ser Asp Gin Ser 20 (2) INFORMATION FOR SEQ ID NO: 10: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 16 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 10: Leu Asp Val Thr Thr Asn Ala Thr He Ala Gly Lys Gly Thr Val Val 1 5 10 15 (2) INFORMATION FOR SEQ ID NO: 11: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 17 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 11: He Phe Asp Thr Thr Leu Asn Pro Thr He Ala Gly Ala Gly Asp Val 1 5 10 15 Lys (2) INFORMATION FOR SEQ ID NO: 12: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 18 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 12: Val Asp He Thr Thr Leu Asn Pro Thr He Ala Gly Cys Gly Ser Val 1 5 10 15 Ala Lys (2) INFORMATION FOR SEQ ID NO: 13: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 19 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown ( ii ) MOLECULE TYPE : peptide ( xi ) SEQUENCE DESCRIPTION : SEQ ID NO : 13 : Cys Val Phe Asp Val Thr Thr Leu Asn Pro Thr He Ala Gly Ala Gly 1 5 10 15 Asp Val Lys (2) INFORMATION FOR SEQ ID NO: 14: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 23 amino acids (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: unknown (ii) MOLECULE TYPE: peptide (xi) SEQUENCE DESCRIPTION: SEQ ID NO: 14: Cys Asp Asn Glu Asn Gin Ser Thr Val Lys Thr Asn Ser Val Pro Asn 1 5 10 15 Met Ser Leu Asp Gin Ser Lys 20

Claims: CLAIMS: 1. A peptide derived from the variable domain of C. pneumoniae MOMP protein, for use in the diagnosis of C. pneumoniae infections, said peptide comprising between 9-40 amino acids and being able to react with antibodies formed during infection with C. pneumoniae, further characterized by having essentially very low cross-reactivity towards antibodies against other Chlamydia species. 2. A peptide or mixture of peptides derived from the variable domains of the Chlamydia pneumoniae (C. pneumoniae) immunodominant major outer membrane protein (MOMP), said mixture characterized by having specificity essentially only to C. pneumoniae anti-MOMP antibodies and being of essentially very low cross reactivity with anti-MOMP antibodies of other Chlamydia species and said mixture also characterized by having specificity to anti-MOMP antibodies from all variants of C. pneumoniae, said peptide or mixture of peptides comprising one to five peptides selected from the group of peptides consisting of: (a) SEQ. ID NO. 1, herein also designated as CplA, having the amino acid sequence: CFSMGAKPTGSAAANYTTANDRPNPAYNK; (b) SEQ. ID NO. 2, herein also designated as Cp2A, having the amino acid sequence: VKGTTNNANELPNVSLSNGK; (c) SEQ. ID NO. 3, herein also designated as CpVDIII, having the amino acid sequence: AFPLPTDAGVATATGTKS; (d) SEQ. ID NO. 4, herein also designated as Cp4A, having the amino acid sequence: LNLTAWNPSLLGNATALSTTDSFK; (e) SEQ. ID NO. 5, herein also designated as C.p NDI, having the amino acid sequence: ΝYTTANDRPΝ; (f) SEQ. ID NO. 6, herein also designated as C.p NDIN, having the amino acid sequence: SLLGΝASTTDSFDFMQIN; (g) SEQ. ID NO. 7, herein also designated as CplAimp, having the amino acid sequence: CFSMGAKPTGSAAANYTTAVDRK; (h) analogs of any one of peptides (a)-(h), wherein said analogs have essentially the same biological activity as said peptides (a)- (g), said analogs having between about 15 to about 40 amino acid residues and differing from said peptides (a)-(g) by having one or more additions, deletions or substitutions. Analogs also comprise peptides obtained by combining an N-terminal part of one peptide with a C-terminal part of another peptide derived from the same variable domain such that the complete sequence will be homologous to the said variable domain sequence. 3. A mixture of peptides according to claim 2 being a mixture of 4 peptides (a), (b), (c) and (d), or a mixture of one or more of said peptides (a)-(d) with one or more analogs of (a)-(d), wherein, when said mixture contains 4 peptides selected from any of the possible combinations of (a) or analog of (a) + (b) or analog of (b) + (c) or analog of (c) + (d) or analog of (d). 4. A mixture of peptides according to claim 2 being a mixture of 4 peptides (b), (c), (d) and (g), wherein, when said peptides and said analogs constitute said mixture, the mixture contains 4 peptides selected from any of the possible combinations of (b) or analog of (b) + (c) or analog of (c) + (d) or analog of (d) + (g) or analog of (g). 5. A mixture of peptides according to claim 2 or claim 3 being a mixture of said peptides (a), (b), (c) and (d), wherein said peptides are present in said mixture in equal amounts. 6. A mixture of peptides according to claim 2 or claim 4 being a mixture of said peptides (b), (c), (d) and (g), wherein said peptides are present in said mixture in equal amounts. 7. A kit for the diagnosis of C. pneumoniae according to any one of claims 1-6, said kit being selected from RIA, EIA, ELISA, Immuno competition assays, lateral chromatography assays, and the SeroRapid ® assay. 8. A kit for the diagnosis of C. pneumoniae infection comprising peptides or a mixture of peptides according to any one of claims 1-6, and manufacturer's instructions for use of said kit. 9. A kit according to claim 8, wherein said kit is for carrying out an enzyme linked immunoserological assay (ELISA), and said kit comprises the mixture of peptides immobilized on a solid support and the reagents for performing said ELISA. 10. Use of a mixture of peptides according to any one of claims 1-6, for the preparation of a diagnostic kit for the detection of C. pneumoniae infection. 11. The mixture of peptides according to any one of claims 1-6 for use in the preparation of a diagnostic kit for the detection of C. pneumoniae infection. 12. A method for detecting C. pneumoniae infection in an individual comprising: (a) obtaining a body fluid sample from said individual; (b) contacting said body fluid sample with a mixture of peptides according to any one of claims 1-6 under suitable assay conditions; and (c) determining the extent of reaction between said body fluid sample and said mixture of peptides. 13. A method according to claim 12, wherein said method comprises performing a diagnostic assay of the ELISA type, wherein said mixture of peptides is immobilized on a solid support, and then contacted under suitable ELISA conditions with said body fluid sample and wherein if said body fluid sample contains antibodies specific for C. pneumoniae MOMP, there will be a detectable positive reaction with said mixture of peptides. 14. A method according to claims 12 or 13, wherein the body fluid sample is selected from sputum, bronchiolar lavage, serum, saliva, tear fluid, urine, semen, and cervical smears. 15. Use of the mixture of peptides according to any one of claims 2-6 in a diagnostic method according to claim 12 or claim 13. 16. A kit according to claim 8 or 9, wherein said kit is capable of detecting the presence of IgA and/or IgG and/or IgM anti-MOMP antibodies specific to C. pneumoniae, when said antibodies are present in the test body fluid sample being assayed. 17. A conjugate of any one or a mixture of the peptides according to claim 1 with a detectable marker for use in an immunoassay. 18. Use of any one or a mixture of the peptides of claims 1 or 2 for the preparation of a vaccine. 19. A peptide according to claim 1 or 2, for use in an immunoassay procedure. 20. Use of a peptide according to claim 1 or 2 in the preparation of a reagent for an immunoassay or a kit according to claim 8, substantially as described in the specification.

Inventors: OHANA BELLA, OHANA, BELLA
Applicants: OHANA BELLA, SAVYON DIAGNOSTICS LTD, OHANA, BELLA, SAVYON DIAGNOSTICS LTD.
Application year: 1998
Main classification: C07K14
IPC codes: A61K39, C07K14