RECOMBINANT MYCOPLASMA HYOPNEUMONIAE VACCINE

Abstract: A Mycoplasma hyopneumoniae protein prepared by recombinant DNA or synthetic means, DNA sequences coding for the protein, an expression vector and transformed host containing the DNA sequences, a vaccine based on the protein, a vaccine based on the DNA sequences, methods of treating swine to prevent enzootic pneumonia using the vaccines, and diagnostic tests based on the protein or antibodies raised against it for detecting the presence of Mhyo infection in swine herds.

Description: RECOMBINANT MYCOPLASMA HYOPNEUMONIAE VACCINE This application claims the benefit of U.S. Provisional Application No. 60/066,565 filed November 26, 1997, which is herein incorporated by reference. FIELD OF THE INVENTION The present invention relates to Mycoplasma hyopneumoniae (M. hyopneumoniae or Mhyo) and more particularly to an antigenic Mhyo protein. Still more particularly, this invention relates to a vaccine for protecting against enzootic pneumonia, and in particular enzootic pneumonia in swine. BACKGROUND OF THE INVENTION Enzootic pneumonia in swine, also called mycoplasmal pneumonia, is caused by Mhyo. The disease is a chronic, non-fatal disease affecting pigs of all ages. Infected pigs show only mild symptoms of coughs and fever, but the disease has significant economic impact due to reduced feed efficiency and reduced weight gain. Enzootic pneumonia is transmitted from pig to pig through the nasal passages by airborne organisms expelled from the lungs of infected pigs. The primary infection by Mhyo may be followed by secondary infection by other mycoplasma species (Mycoplasma hyorhinis and Mycoplasma flocculare) as well as other bacterial pathogens. Mhyo is a small, prokaryotic microbe capable of a free living existence, although it is often found in association with eukaryotic cells because it has absolute requirements for exogenous sterols and fatty acids. These requirements generally necessitate growth in seπim-contaming media. Mhyo is bounded by a cell membrane, but not a cell wall. The genome of Mhyo is approximately 1,000,000 base pairs in length. The physical association of mycoplasmas with the host cell surface is the basis for the development and persistence of enzootic pneumonia. Mhyo infects the respiratory tract of swine, colonizing the trachea, bronchi, and bronchioles. The mycoplasma produces a ciliostatic factor which causes the cilia lining the respiratory passages to stop beating. Eventually, the cilia degenerate, leaving the pig prone to infection by secondary pathogens. Characteristic lesions of purple to gray areas of consolidation are observed in infected animals. Surveys of slaughtered animals revealed lesions in 30 to 80% of swine. Results from 37 herds in 13 states indicated that 99% of the herds had hogs with pneumonia lesions typical of enzootic pneumonia. Therefore, the need for effective preventative and treatment measures are great. Antibiotics such as tiamulin, trimethoprim, tetracyclines and lincomycin have some benefit, but are expensive and require prolonged use. Additionally, antibiotics have not been shown to effectively eliminate spread or reinfection of Mhyo. Prevention by mamtaining pathogen-free herds is sometimes possible but reintroduction of Mhyo often occurs. Due to the serious economic consequences of swine pneumonia, vaccines against Mhyo and diagnostic testing methods which will indicate the presence of an infection have been sought. Vaccines containing preparations of mycoplasmal organisms grown in serum-containing medium have been marketed, but are expensive and raise concerns regarding adverse reactions induced by serum components present in the immunizing material. Other attempts to provide vaccines have not been successful, and the disease remains widespread. What is needed is a vaccine against mycoplasma infection in swine, and a cost-effective process of producing the same. Also needed is a diagnostic test for detecting the presence of swine mycoplasma infection in swine herds. SUMMARY OF THE INVENTION The present invention provides purified or isolated Mycoplasma hyopneumoniae protein PI 02 prepared by recombinant or synthetic means, and polypeptides or peptides that are portions of PI 02 and which when administered to a swine elicit the formation of antibodies that bind to Mhyo. Preferred PI 02 and polypeptides have an amino acid sequence as shown in Fig. 1, or a fragment of such sequence. Also provided are recombinant DNA molecules useful in preparing PI 02 and the aforementioned polypeptides. Preferred recombinant DNA molecules are characterized by a DNA sequence selected from the sequence shown in Fig. 2, DNA sequences encoding the amino acid sequences shown in Figs. 1 and 5, DNA sequences that hybridize to any of those DNA sequences and that code for Mhyo P102, DNA sequences that code for an antigen oi Mhyo coded by any of the foregoing DNA sequences, and DNA sequences which are degenerate as a result of the genetic code to the aforementioned DNA sequences and which code for an antigen of Mhyo. Expression vectors and host cells containing the proteins or DNA sequences of the present invention are also provided. The present invention also includes a vaccine for immunizing swine against Mhyo infections by administering the produced and subsequently isolated PI 02, polypeptides, or an expression vector containing the DNA sequences of the present invention to swine (e.g., by injection), in an amount sufficient to elicit the formation of antibodies. A diagnostic test based on PI 02, the polypeptides of the present invention, or antibodies raised against them is also provided for testing swine herds for Mhyo infections. Additional advantages and features of the present invention will be apparent from the following detailed description, drawings and examples which illustrate preferred embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 depicts the amino acid sequence of PI 02. Figure 2 depicts the DNA sequence encoding Mhyo PI 02. Figure 3 depicts a restriction map of clones of the P97 operon. Figure 4 depicts a restriction map of the PI 02 clones. Figure 5 depicts the alignment of the translated amino acid sequences of PI 02 with the sequences of several clones. Figure 6 depicts the open reading frames of the P97 contig, and the probes used to screen the genomic library. Figure 7 depicts the results of a hybridization analysis of Mhyo DNA with the probes of Fig. 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the presently preferred embodiments of the invention, which, together with the drawings and the following examples, serve to explain the principles of the invention. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized, and that structural and chemical changes may be made without departing from the spirit and scope of the present invention. The following abbreviations are used in this application: aa, amino acid(s); Ab, antibody(ies); bp, base pair(s); CHEF, clamped homogenous electric field; H., Haemophilur, kb, kilobase(s) or 1000 bp; Kn, kanamycin; LB, Luria- Bertoni media; Λf., Mycoplasma; mAb, monoclonal Ab; ORF, open reading frame; PCR, polymerase chain reaction; R , resistant/resistance; Tn, transposon(s); ::, novel junction (fusion or insertion). One letter and three letter code designations for amino acids are given in Table 1 , below. The term "protein" used in the following description refers to a microbially expressed protein that has been separated, isolated, or purified from other proteins, whole bacteria, and cellular substances by conventional means such as preparative chromatography, immunological separation, or passage through a metal chelate column. The term "mutant" as used in the following description refers to an amino acid or DNA sequence having minor modifications or conservative variations such that the sequence results in proteins having substantially equivalent function when compared to native Mhyo PI 02. The term "conservative variations" denotes the replacement of an amino acid residue by another, biologically similar residue, or the substitution of nucleotides in a DNA sequence to achieve the same result. Examples of conservative variations include the substitution of one hydrophobic residue such as isoleucine, valine, leucine or methionine for another, or the substitution of one polar residue for another, such as the substitution of arginine for lysine, glutamic for aspartic acids, or glutamine for asparagine, and the like. The term "conservative variation" also includes the use of a substituted amino acid in place of an unsubstituted parent amino acid provided that antibodies raised to the substituted polypeptide also immunoreact with the unsubstituted polypeptide. The present invention concerns the Mycoplasma hyopneumoniae protein PI 02, in an isolated, purified, and/or recombinant form, and the use of PI 02, or fragments thereof, as a vaccine or diagnostic tool in swine. PI 02, which has been shown by the inventors to cause an immunological reaction in swine protected against virulent challenge, has been isolated, characterized, and named by the present inventors. Also within the scope of the present invention are DNA sequences corresponding to recombinant PI 02, and expression vectors and hosts containing such sequences. A vaccine containing isolated, purified, and/or recombinant P102, or DNA sequences encoding P102 for immunizing swine against Mhyo infections, and a diagnostic tool based on PI 02 useful in testing swine herds for infections are also provided. Any Mhyo strain may be used as a starting material to produce the PI 02 of the present invention. Suitable strains of Mhyo may be obtained from a variety of sources, including depositories such as the American Type Culture Collection (ATCC) (Manassas, VA) and the NRRL Culture Collection (Agricultural Research Service, U.S. Department of Agriculture, Peoria, IL). The ATCC alone lists six strains of Mhyo for sale. In view of the widespread dissemination of the disease, strains may also be obtained by recovering Mhyo from lung secretions or tissue from sick animals and inoculating suitable culture medium. Referring now to the drawings, the amino acid sequence of Mhyo P102 is shown in Fig. 1. As can be seen, P102 comprises 904 amino acids, the distribution of which is detailed in Table 2, below. PI 02 lacks cysteine, and has an isoelectric point (pi) of 9.28. The protein was designated as "P102" due to its 102.3 kiloDalton weight. It is believed that P102 may be a membrane- spanning protein, due to the presence of a putative 25 amino acid membrane - spanning domain at the N-terminus of the protein (aa 10-34). While not wishing to be bound by theory, the remainder of the protein sequence is currently believed to form one or more α-helices because of the high percentage (-64%) of α-helix forming amino acids present therein. The proteins or polypeptides of the present invention have an amino acid sequence as shown in Fig. 1, or a fragment or mutant of said sequence capable of eliciting an antibody or other immune response which recognizes an epitope of the amino acid sequence depicted in Fig. 1. Mutations at either the amino acid or encoding DNA level may be useful in improving the yield of the proteins, their immunogenicity or antigenicity, or their compatibility with various purification schemes, adjuvants and modes of administration. Such fragments and mutations, synthetic or recombinant, are characterized by one or more of the antigenic sites of native Mhyo PI 02. The proteins or polypeptides of the present invention may be purified or isolated proteins or polypeptides extracted from Mhyo cells, or may be recombinant proteins or polypeptides produced in hosts transformed by DNA sequences coding for those recombinant proteins or polypeptides. It should of course be understood that these proteins or polypeptides may include residues that are not related to Mhyo. For example, the recombinant proteins or polypeptides of this invention may be fusion proteins containing a protein portion derived from an expression vector or other source and a protein portion derived from Mhyo. These recombinant polypeptides and fusions of them may also include a starting met-hionine. All that is required is that the final polypeptides display the antigenicity of native Mhyo PI 02. The recombinant DNA sequence encoding the PI 02 of the present invention, which comprises 2712 base pairs, is shown in Fig. 2. The sequence depicted is of the non-template strand, with the 5' end on the left and the 3' end on the right, so that mRNA produced from the complementary template strand will have a sequence identical to that shown in Fig. 2 except for the substitution of uracil (U) for thymine (T). The start codon (ATG) and stop codon (TAA) are underlined. Approximately 24 base pairs upstream of the start codon, including a putative Shine Dalgarno sequence (GGAGGT) 10 base pairs upstream of the start codon, and 21 base pairs downstream of the stop codon are also shown. The PI 02 sequence has no significant match to any known sequence, including other bacterial adhesin genes. The present invention concerns any DNA sequence coding for a protein which is capable of eliciting an antibody or other immune response (e.g., T-cell response of the immune system) which recognizes an epitope of the amino acid sequence depicted in Fig. 1, including less than the full DNA sequence and mutants thereof. Hence the DNA sequence of the present invention may encode proteins or polypeptides which may be the full length antigen, antigen fragment, antigen derivative or a fusion product of such antigen, antigen fragment or antigen derivative with another protein. Recombinant DNA molecules that are useful in preparing the aforementioned proteins and polypeptides are also provided. Preferred recombinant DNA molecules are characterized by a DNA sequence selected from the sequence shown in Fig. 2, cloning or expression vectors containing a sequence encoding a recombinant protein or polypeptide of the present invention, as described above, DNA sequences that hybridize to any of those DNA sequences and that code for Mhyo P102, DNA sequences that code for an antigen of Mhyo coded by any of the foregoing DNA sequences, and DNA sequences which are degenerate as a result of the genetic code to the aforementioned DNA sequences and which code for an antigen of Mhyo. The appropriate DNA sequence may be inserted into any of a wide variety of expression vectors by a variety of procedures, generally through use of an appropriate restriction endonuclease site. Suitable vectors include, for example, vectors consisting of segments of chromosomal, non-chromosomal and synthetic DNA sequences, such as various known derivatives of SV40, known bacterial plasmids, e.g., plasmids from E. coli including col El, pCRl, pBR322, pMB9 and their derivatives, wider host range plasmids, e.g., RP4, phage DNAs, e.g., the numerous derivatives of phage λ, e.g., NM 989, and other DNA phages such as Ml 3 or filamentous single stranded DNA phages, yeast plasmids such as the 2μ plasmid or derivatives thereof, viral DNA such as baculovirus, vaccinia, adenovirus, fowl pox virus, or pseudorabies, and vectors derived from combinations of plasmids and phage DNAs, such as plasmids which have been modified to employ phage DNA or other expression control sequences. Wit-hi each specific cloning or expression vehicle, various sites may be selected for insertion of the DNA sequences of this invention. These sites are usually designated by the restriction endonuclease which cuts them and there are various known methods for inserting DNA sequences into these sites to form recombinant DNA molecules. These include, for example, dG-dC or dA-dT tailing, direct ligation, synthetic linkers, exonuclease and polymerase-linked repair reactions followed by ligation, or extension of the DNA strand with DNA polymerase and an appropriate single-stranded template followed by ligation. It is, of course, to be understood that a cloning or expression vehicle useful in this invention need not have a restriction endonuclease site for insertion of the chosen DNA fragment, and that insertion may occur by alternative means. For expression of the DNA sequences of this invention, these DNA sequences are operatively linked to one or more expression control sequences in the expression vector. Such operative li-nking, which may be effected before or after the chosen DNA sequence is inserted into a cloning vehicle, enables the expression control sequences to control and promote the expression of the inserted DNA sequence. Any of a wide variety of expression control sequences - sequences that control the expression of a DNA sequence when operatively linked to it - may be used in these vectors to express the DNA sequences of this invention. Such useful expression control sequences include, for example, the early and late promoters of SV40, the lac or trp systems, the TAC or TRC system, the major operator and promoter regions of phage λ, the control regions of fd coat protein, the promoter for 3-phosphoglycerate kinase or other glycolytic enzymes, the promoters of acid phosphatase, e.g., Pho5, the promoters of the yeast α- mating factors, and other sequences known to control the expression of genes in prokaryotic or eukaryotic cells or their viruses, and various combinations thereof. The expression vector also includes a non-coding sequence for a ribosome binding site for translation initiation and a transcription terminator. The vector may also include appropriate sequences for amplifying expression. In mammalian cells, it is additionally possible to amplify the expression units by linking the gene to that coding for dehydrofolate reductase and applying a selection to host Chinese hamster ovary cells. The vector or expression vehicle, and in particular the sites chosen therein for insertion of the selected DNA fragment and the expression control sequence employed in this invention are determined by a variety of factors, e.g., number of sites susceptible to a particular restriction enzyme, size of the protein to be expressed, expression characteristics such as the location of start and stop codons relative to the vector sequences, and other factors recognized by those of skill in the art. The choice of a vector, expression control sequence, and insertion site is determined by a balance of these factors, not all selections being equally effective for a given case. In the preferred embodiments of this invention, various clones may be used, including those shown in Figs. 3 through 5. Fig. 3 depicts a restriction map of various overlapping clones of the P97 operon, which includes the genes for Mhyo proteins P97 and PI 02. These clones were obtained by DNA hybridization with a cloned fragment from pISMl 161. The position of the P97 structural gene, its direction of transcription (arrow), and the region of DNA sequence analysis (dark bar) are shown. Sites are given in kilobases. Restriction enzymes are abbreviated as follows: A, Accl; B, BamHI; Bg, Bglll; C, CM; E, EcoRl; EV, EcoKV; H, Hindlll; Hn, Hin ll; N, N il; S, Sail. Fig. 4 illustrates a restriction map of the P102-related clones of the present invention. The physical map of the P97 contig with the P97 and P102 gene boundaries is shown as a reference, and the direction of transcription is left to right. The homologies between the DNA sequences of clones pISM1232-34 and pISM2166 and the P97 operon sequence are indicated as shaded or hatched regions, with light gray indicating high (>95%) PI 02 homology, black indicating reduced (<75%) to no PI 02 homology, dark gray indicating no P97 homology, and hatched regions indicating regions for which no DNA sequence information was available. The positions of plasmids pISM1165, pISM1168, pISM1169, pISM1170, and pISM1174 relative to pISM1232 and pISM1233 are shown. Restriction patterns are given for each clone or group of clones, and size is given in kilobases. The alignment of the translated amino acid sequences of the PI 02 clones pISM2166, pISM1232, pISM1233, and pISM1234 with native P102 is shown in Fig. 5. Alignment of the P102 amino acid sequences was done using Clustal W alignment in MacVector™ software version 6.0.1 (Oxford Molecular Group, Campbell, CA). Boxed areas indicate identity or similarity in the sequence. pISM1232/3 indicates alignment for both pISM1232 and pISM1233. Sequences for pISM1232 are shown at the beginning of the alignment and sequences for pISM1233 are shown at the end of the alignment. The recombinant DNA molecule containing the desired gene operatively linked to an expression control sequence may then be employed to transform a wide variety of appropriate hosts so as to permit such hosts (transformants) to express the gene, or fragment thereof, and to produce the polypeptide, or portion thereof, for which the hybrid DNA codes. The recombinant DNA molecule may also be employed to transform a host so as to permit that host on replication to produced additional recombinant DNA molecules as a source of Mhyo genes and fragments thereof. A wide variety of hosts are also useful in producing the antigens and DNA sequences of this invention. These hosts include, for example, bacteria such as -E. coli, Bacillus and Streptomyces, fungi such as yeasts, and animal or plant cells in tissue culture. The selection of an appropriate host for either of these uses is controlled by a number of factors. These include, for example, compatibility with the chosen vector, toxicity of the co-products, ease of recovery of the desired polypeptide, expression characteristics, biosafety and costs. No absolute choice of host may be made for a particular recombinant DNA molecule or polypeptide from any of these factors alone. Instead, a balance of these factors must be struck with the realization that not all hosts may be equally effective for expression of a particular recombinant DNA molecule. It is also understood that the DNA sequences that are inserted at the selected site of a cloning or expression vehicle may include nucleotides which are not part of the actual gene coding for the desired polypeptide or may include only a fragment of the entire gene for that protein. It is only required that whatever DNA sequence is employed, the transformed host produces a polypeptide having the antigenicity of native Mhyo PI 02. For example, the DNA sequences of this invention may be fused in the same reading frame in an expression vector of this invention to a portion of a DNA sequence coding for at least one eukaryotic or prokaryotic carrier protein or a DNA sequence coding for at least one eukaryotic or prokaryotic signal sequence, or combinations thereof. Such constructions may aid in expression of the desired DNA sequence, improve purification or permit secretion, and preferably maturation, of the desired polypeptide from the host cell. The DNA sequence may alternatively include an ATG start codon, alone or together with other codons, fused directly to the sequence encoding the first amino acid of a desired polypeptide. Such constructions enable the production of, for example, a methionyl or other peptidyl polypeptide that is part of this invention. This N- terminal methionine or peptide may then be cleaved intra- or extra-cellularly by a variety of known processes or the polypeptide used together with the met-hionine or other fusion attached to it in the compositions and methods of this invention. The appropriate DNA sequence present in the vector when introduced into a host may express part or only a portion of the protein which is encoded, it being sufficient that the expressed protein be capable of eliciting an antibody or other immune response which recognizes an epitope of the amino acid sequence depicted in Fig. 1. For example, in employing E. coli as a host organism, the UGA codon is a stop codon so that the expressed protein may only be a fragment of the antigen encoded into the vector and for this reason it is generally preferred that all of the UGA codons in the appropriate DNA sequence be converted into non-stop codons. Another way around the problem in a host that recognizes UGA as a stop codon is to include an additional DNA sequence which encodes a t-RNA which translates the UGA codon wit-hin a protein coding sequence as tryptophan in the transformed organism. The protein expressed by the host transformed by the vector may be harvested by methods which will occur to those skilled in the art, and used in a vaccine for protection of a non-human animal such as swine, cattle, etc. against enzootic pneumonia caused by Mhyo. The protein is used in an amount effective to provide protection against enzootic pneumonia caused by Mhyo and may be used in combination with an suitable physiologically acceptable carrier, as is described below in more detail. In a preferred embodiment of the invention, the gene sequence for PI 02 was cloned into the expression vector pTrcHis Xpress available from Invitrogen Corp. (Carlsbad, CA). An E. coli host was transformed with the vector, and PI 02 protein was produced at high levels. The pTrcHis Xpress vector produced a fusion protein comprising PI 02 fused to a short leader peptide with six histidine residues in tandem. The cells were then lysed, and PI 02 was purified by -running the crude cell lysate through a metal chelate column, such as a ProBond column (Invitrogen, Carlsbad, CA). The recombinant proteins and polypeptides of the present invention may also be used as antigens for diagnostic purposes to determine whether or not a biological test sample contains Mhyo antigens or antibodies to these antigens. Such an assay for Mhyo infection in an animal typically comprises incubating an antibody-containing biological sample from an animal suspected of having such a condition in the presence of a detectably labeled recombinant protein of the present invention, and detecting binding. Thus, in this aspect of the invention, t e recombinant proteins may be associated with a solid phase support, e.g., a microtiter plate, which is capable of immobilizing cells, cell particles or soluble proteins. The support may then be washed with suitable buffers followed by treatment with the sample containing antibody. The solid phase support may then be washed with the buffer a second time to remove unbound antibody. Labeled recombinant protein is added and the support is washed a third time to remove unbound labeled antigen. The amount of bound label on said solid support may then be detected by conventional means. By "solid phase support" is intended any support capable of binding antigen or antibodies. Well-known supports, or carriers, include glass, polystyrene, polypropylene, polyethylene, dextran, nylon, amylases, natural and modified celluloses (especially nitrocellulose), polyacrylamides, agarose, and magnetite. The nature of the carrier can be either soluble to some extent or insoluble for the purposes of the present invention. The support material may have virtually any possible structural configuration so long as the coupled molecule is capable of binding to an antigen or antibody. Thus, the support configuration may be spherical, as in a bead, or cylindrical, as in the inside surface of a test tube, or the external surface of a rod. Alternatively, the surface may be flat such as a sheet, test strip, etc. Preferred supports include polystyrene beads. One of the ways in which the Mhyo specific antibody can be detectably labeled is by linking the same to an enzyme and using it in an enzyme immunoassay (EIA), or enzyme -linked immunosorbent assay (ELIS A). This enzyme, in turn, when later exposed to its substrate, will react with the substrate in such a manner as to produce a chemical moiety which can be detected, for example, by spectrophotometric, fluorometric or by visual means. Enzymes which can be used to detectably label the Mhyo specific antibody include, but are not limited to, horseradish peroxidase, malate dehydrogenase, staphylococcal nuclease, delta- V-steroid isomerase, yeast alcohol dehydrogenase, alpha- glycerophosphate dehydrogenase, triose phosphate isomerase, alkaline phosphatase, asparaginase, glucose oxidase, beta-galactosidase, ribonuclease, urease, catalase, glucose-6-phosphate dehydrogenase, glucoa/nylase and acetylcholinesterase. Detection may be accomplished using any of a variety of immunoassays. For example, by radioactively labeling the recombinant protein, it is possible to detect antibody binding through the use of a radioimmunoassay (RIA). The radioactive isotope can be detected by such means as the use of a gamma counter or a scintillation counter or by autoradiography. Isotopes which are particularly useful for the purpose of the present invention are 3 H, 125 I, 131 I, 35 S, and 14 C, preferably 125 I. It is also possible to label the recombinant protein with a fluorescent compound. When the fluorescently labeled protein is exposed to light of the proper wavelength, its presence can then be detected due to fluorescence. Among the most commonly used fluorescent labeling compounds are fluorescein isothiocyanate, rhodamine, phycoerytherin, phycocyanin, allophycocyanin, o- phthaldehyde and fluorescamine. The protein can also be detectably labeled using fluorescence emitting metals such as 152 Eu, or others of the lanthanide series. These metals can be attached to the protein using such metal chelating groups as diet-hylenetriaminepentaacetic acid (DTP A) or ethylenediamine- tetraacetic acid (EDTA). The protein also can be detectably labeled by coupling it to a chemiluminescent or bioluminescent compound. The presence of the chemUuminescent-tagged protein is then determined by detecting the presence of luminescence that arises during the course of a chemical reaction. Bioluminescence is a type of chemiluminescence found in biological systems in which a catalytic protein increases the efficiency of the chemiluminescent reaction. Examples of particularly useful chemiluminescent labeling compounds are luminol, isoluminol, theromatic acridinium ester, imidazole, acridinium salt and oxalate ester. Important bioluminescent compounds for purposes of labeling are luciferin, luciferase and aequorin. Detection of the label may be accomplished by a scintillation counter, for example, if the detectable label is a radioactive gamma emitter, or by a fluorometer, for example, if the label is a fluorescent material. In the case of an enzyme label, the detection can be accomplished by colorimetric methods which employ a substrate for the enzyme. Detection may also be accomplished by visual comparison of the extent of enzymatic reaction of a substrate in comparison with similarly prepared standards. The detection of foci of detectably labeled antibodies is indicative of a disease or dysfunctional state and may be used to measure Mhyo in a sample. The absence of such antibodies or other immune response indicates that the animal has been neither vaccinated nor infected. Eor the purposes of the present invention, the bacteria which is detected by this assay may be present in a biological sample. Any sample containing it can be used, however, one of the benefits of the present diagnostic invention is that invasive tissue removal may be avoided. Therefore, preferably, the sample is a biological solution such as, for example, nasal, throat or lung fluid, but the invention is not limited to assays using these samples. In situ detection may be accomplished by removing a histological specimen from an animal, and providing the combination of labeled antibodies of the present invention to such a specimen. The antibody (or fragment) is preferably provided by applying or by overlaying the labeled antibody (or fragment) to a biological sample. Through the use of such a procedure, it is possible to determine not only the presence of Mhyo but also the distribution of it in the examined tissue. Using the present invention, those of ordinary skill will readily perceive that any of a wide variety of histological methods (such as staining procedures) can be modified in order to achieve such in situ detection. Alternatively, a fluid sample may be tested for the presence of a gene for Mhyo PI 02 by reaction with a recombinant or synthetic DNA sequence contained wit-hin the sequence shown in Fig. 2 or any RNA sequence equivalent to said DNA sequence. The absence of the gene indicates that the animal has been neither vaccinated nor infected. This test involves methods of synthesis, amplification or hybridization of nucleic acid sequences which are known to those skilled in the art. The present invention also contemplates a vaccine, comprising the recombinant proteins and polypeptides of the present invention, or DNA sequences encoding these proteins and polypeptides, for immunizing or protecting non-human animals, preferably swine, against Mhyo infections, particularly enzootic pneumonia. The terms "protecting" or "protection" when used with respect to the vaccine for enzootic pneumonia described herein means that the vaccine prevents enzootic pneumonia caused by Mhyo and/or reduces the severity of the disease. A vaccine based on the DNA sequences of the present invention may be made by removing UGA codons and introducing the chosen sequence into a suitable vector. The vaccine may then be administered by suitable methods such as particle bombardment, microinjection, electroporation, calcium phosphate transfection, liposomal transfection, and viral transfection. DNA vaccines and methods of their administration are known in the art, and are described in U.S. Patent Nos. 5,836,905; 5,703,055; 5,589,466; and 5,580,859, which are herein incorporated by reference. The vaccine is employed in conjunction with a carrier, which may be any of a wide variety of carriers. Representative carriers include sterile water, saline, buffered solutions, mineral oil, alum, synthetic polymers, etc. Additional agents to improve suspendability and dispersion in solution may also be used. The selection of a suitable carrier is dependent upon the manner in which the vaccine is to be administered. The vaccine is generally employed in non-human animals which are susceptible to enzootic pneumonia, and in particular swine. The vaccine may be administered by any suitable method, such as intramuscular, subcutaneous, intraperitoneal or intravenous injection. Alternatively, the vaccine may be administered intranasally or orally, such as by mixing the active components with feed or water, providing a tablet form, etc. Methods such as particle bombardment, microinjection, electroporation, calcium phosphate transfection, liposomal transfection, and viral transfection are particularly suitable for administering a DNA sequence vaccine. Other means for administering the vaccine will be apparent to those skilled in the art from the teachings herein; accordingly, the scope of the invention is not limited to a particular delivery form. The vaccine may also include active components or adjuvants (e.g., Freund's incomplete adjuvant) in addition to the antigen(s) or fragments hereinabove described. Adjuvants may be used to enhance the immunogenicity of an antigen. The mechanism of how adjuvants operate is not entirely known. Some are believed to enhance the immune response by slowly releasing the antigen while other adjuvants are believed to function synergistically. Among the adjuvants which may be used are oil and water emulsions, complete Freund's adjuvant, incomplete Freund's adjuvant, Corynebacterium parvum^ Hemophilus, Mycobacterium butyricum, aluminum hydroxide, dextran sulfate, iron oxide, sodium alginate, Bacto-Adjuvant, certain synthetic polymers such as poly amino acids and co-polymers of amino acids, saponin, iota carrageenan, Regressin™, Avridine™, Mannite monooleate, paraffin oil, and muramyl dipeptide. Application of the teachings of the present invention to a specific problem or environment is within the capabilities of one having ordinary skill in the art in fight of the teachings contained herein. Examples of the products and processes of the present invention appear in the following examples. EXAMPLE 1 Library Construction and Screening A Mhyo chromosomal DNA genomic library was constructed with Tsp5091 -digested chromosomal DNA cloned into EcoBI λ ZAP II as described previously in -Minion, F.C., VanDyk, C. and Smiley, B.K., "Use of an Escherichia coli enhanced opal suppressor strain to screen a Mycoplasma hyopneumoniae library", 131 FEMS Microbiol. Letters 81 -85 (1995), which is herein incorporated by reference. The library was grown on E. coli strain LE392 using the technique described in Hanahan, D., "Studies on transformation of Escherichia coli with plasmids", 166 /. Mol. Biol 557-80 (1983), and screened by DNA hybridization using the method of Sambrook, J., Fritsch, E.F. and Maniatis, T., Molecular cloning: A Laboratory Manual, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1989), and with swine convalescent antisera as described in Minion et al. Fig. 6 illustrates the open reading frames of the P97 contig, and the probes used to screen the genomic library. Boxes indicate ORFs with their designations given below. Shaded boxes indicate transcription from left to right; white boxes indicate transcription from right to left. Probes 1-4 used for hybridization analysis, and probe 5 used in screening the genomic library are shown below the figure. Hybridization was carried out overnight with 32 P radiolabeled probes at 65°C. One hybridization probe was the 3.3-kb cloned fragment from pISMllόl containing the N-terminus of P97 as well as upstream sequences depicted in Fig. 3. A second probe, probe 5, was a cloned 400-bp fragment of DNA located in the P102 structural gene, as shown in Fig. 6. The library was also screened with Mhyo- fcctcd swine convalescent sera as described previously in Minion et al. Convalescent sera was obtained by the following process. Inoculum was made by removing swine lungs infected with Mhyo from an animal, homogenizing them, and then freezing aliquots. Next, an aliquot of inoculum was diluted 1:10 in steryl phosphate -buffered saline and 10 mL was instilled intertracheally in swine. Blood was drawn to obtain sera after 28 days, or after 56-73 days. Plasmids containing cloned Mhyo chromosomal DNA fragments were excised in vivo from the corresponding purified recombinant λ ZAP II phage with ExAssist™ helper phage (Stratagene, La Jolla, CA) and introduced into the E. coli SOLR™ [el ι-(mcrA) A(mcrCB- hsiSMR-mr^Ul sbcC recB recJuvrC umuC::Tn5(Kn R ) lac£fyrA96 relAl thi-l endAl λ R (F 1 proAB lacl q Z -M5) Su ' ] according to the manufacturer's instructions (Stratagene, La Jolla, CA). EXAMPLE 2 DNA Sequencing and Sequence Analysis ΥΏ.1000- facilitated DNA sequencing was performed on plasmids pISM1210, pISM1217 and PISM2166 as described by Strathmann, M., Hamilton, B.A., Mayeda, C.A., Simon, M.I., Meyerowitz, E.M. and Palazzolo, M.J., "Transposon-facilitated DNA sequencing", 88 Proc. Nat'lAcad. Sci. USA 1247-50 (1991). Matings were performed with E. coli strains DPWC(F + ), as described in Strathmann et al. and BW26 (Kn R recipient). The inserts were mapped by restriction digests using Sail, EcøRV and BamΗI restriction enzymes, and a series of TnlOOO inserts were chosen to use as template DNAs for sequencing reactions based upon their location and their usefulness in adding to the DNA sequence information upstream and downstream of the P97 sequence. DNA sequencing was then performed, as described in Strathmann et al., using the T7 and T3 vector-specific primer sites and TnlOOO end-specific primers 186 (5'-ATATAAACAACGAATTATCTCC-3') and 188 (5 1 - TAAGTTATACCATAAACG-3 1 ) in cycle sequencing reactions. All sequences were obtained using an automated Model 373A Fluorescent DNA sequencer (Perkin-Elmer Applied Biosystems, Inc., Foster City, CA). DNA sequence analysis was performed with MacVector™ software version 6.0.1 (Oxford Molecular Group, Campbell, CA). Translation was performed with a mycoplasma translation table. DNA and translated protein sequence homology searches were accomplished by BLASTN and BLASTP analyses, respectively. EXAMPLE 3 Hybridization Analysis Hybridization analysis was performed on Mhyo chromosomal DNA digested with Hindlll, Hincll, EcoKV, EcoBl, and gfil. The digested DNAs were resolved on 0.7% agarose gels and blotted on to a nylon membrane. Several P97 operon-specific probes, shown in Figs. 3 and 6, were used in the analysis, including a 758-bp EcoBN-Hinάlll fragment of P97 obtained from pISM1213 (probe 1), a PCR product containing the Rl repeat region of P97 that contains the major antigenic and the cilium binding epitopes (probe 2), and the Ncil- Hin ll (probe 3) and Hincϊl-Kpήl (probe 4) fragments from pISM2139. Primers TH120 (5'-AAGGTAAAAGAGAAGAAGTAG) and TH121 (5'-TTGTAAGTGAAAAGCCAGTAT) were used in a PCR reaction mixture containing 2 mM MgCl 2 , 25 pmol of each primer, 1-50 ng template DNA, 1.25 units of Taq DNA polymerase in 50 μl of IX manufacturer's reaction buffer to generate probe 2. The PCR conditions were as follows: the DNA was denatured at 94°C for 5 min, followed by 35 cycles (94°C denaturation for 1 min, 58°C annealing for 1.5 min and 72°C extension for 1 min) and a final 5-min 72°C extension step. Figure 7 depicts the results of a hybridization analysis of Mhyo DNA with the probes of Fig. 6. Each panel represents hybridization with a single probe as indicated at the top of the panel. For probes 1 and 2, the chromosomal DNA was digested with Bjtll. Restriction enzyme digested chromosomal DNAs for probes 3 and 4 were HindUI (lane 1), Hincll (lane 2), EcoKV (lane 3), EcoRl (lane 4), and Bgtll (lane 5). Lane 6 contained 6 ng of control plasmid DNA digested with the enzymes used to isolate the probe. The autoradiographs were digitized using a Cohu model 4900 high-performance CCD camera (Cohu Inc., San Diego, CA) and a Macintosh Hci equipped with a Scion Corporation (Frederick, MD) video board. The size of each band was determined using GelReader software (NCSA, Urbana-Champaign, IL), and the sizes are indicated in kilobases. TIFF files were cropped with and assembled in Adobe Photoshop and labeled in Aldus FreeHand (Adobe Systems Inc., San Jose, CA). EXAMPLE 4 Cloning and Analysis of PI 02 Gene Copies Additional clones of PI 02 were obtained by cloning agarose gel purified 3.8-, 4.2- and 4.8-kb EcoRI fragments of Mhyo chromosomal DNA into EcøRI-digested pBluescript II pSK " (Stratagene, La Jolla, CA). Recombinant clones were then screened by colony blot for PI 02 -specific clones using probe 3 (shown in Fig. 6). These resulting plasmids were restriction mapped and the ends of the cloned fragments sequenced. A sequencing primer (5'- GCGGCTGCTAAACTAAGACTA) was used to obtain additional sequence information of the 3' end of pISM1232 and pISM1234, which was aligned to the P97 contig sequence. An additional clone, pISM2166, which was obtained by screening the genomic library with swine convalescent antisera, was completely sequenced and was found to contain significant homology to PI 02. EXAMPLE 5 Identification and Characterization of the PI 02 Structural Gene All previous recombinant clones containing P97 sequences were identified using mAb F1B6, as described in Hsu, T., Airiushin, S. and Minion, F.C., "Cloning and analysis of P97, a respiratory cilium adhesin gene of Mycoplasma hyopneumoniae", 79 J. Bacteriol. 1317-23 (1997). To obtain additional clones containing the P97 structural gene and its surrounding sequences, we screened the genomic library by hybridization using a probe that contained the P97 5' end and sequences upstream of the translational start codon. An additional clone was identified with PI 02 sequences by screening the library with swine convalescent sera from -Λf/ryσ-infected pigs. The resulting clones were then subjected to DNA sequence and hybridization analyses. Screening of the genomic library with the 3.3-kb fragment from pISMllόl resulted in the identification of clones pISM1210, pISM1212- pISM1214, and pISM1217, as shown in Fig. 3. These plasmids, represented by the two largest plasmids pISM1210 and pISM1217, overlapped a 16-kb region (designated as the P97 contig) corresponding to the upstream and downstream regions of the P97 gene, respectively. Among the clones identified with probe 5 were P ISM1165, pISM1168-pISM1170, and pISM1174 (Fig. 4). A total of 9374 bp of DNA sequence were obtained, including the sequence for P97. Fig. 2 depicts the approximately 2750 bp sequence that includes the PI 02 gene. The complete sequence of the P97 operon has been published previously in Hsu, T. and Minion, F.C., "Molecular analysis of the P97 cilium adhesin operon of Mycoplasma hyopneumoniae", 214 Gene 13-23 (1998), and in Hsu et al. (Accession No. U50901). Computer analysis identified a total of six ORFs in this 9374-bp sequence (Fig. 6). P97 appeared to be the first gene of a two-gene operon, designated as the P97 operon, and depicted in Figs. 4 and 6. The two genes are separated by 20 bp, which includes a putative Shine Dalgamo sequence (GGAGGT) 10 bp upstream of the ATG start codon of the second ORF. This ORF was 2712 bp in length with a coding capacity for a 102.3-kDa protein. This protein was designated as P102, had a calculated pi of 9.28, and lacked Cys (see Table 2 above). The protein was highly hydrophilic with a putative 25-aa membrane - spanning domain at its N- terminus (aa 10-34). A search of the database for homology with P102 revealed no significant match to any known sequence, including other bacterial adhesin genes. The protein structural predictions for PI 02 indicate a high degree of α-helicity following a hydrophobic transmembrane sequence (data not shown). To verify the hypothesis that additional copies of PI 02 were present in the Mhyo chromosome, the additional EcoRI chromosomal fragments recognized by P102-specific probes were cloned and analyzed. Plasmids pISM1232- pISM1234 representing the 3.8-, 4.2- and 4.8-kb fragments, respectively, were restriction-site-mapped. Partial sequencing of the ends of 3.8 and 4.2 kb cloned fragments suggested that these two clones are from a different chromosomal region to the original P102 copy. Alignment of the cloned fragments with the P97 contig is shown in Fig. 4. The DNA sequence of the 3' end of pISM1232 and the 5' end of pISM1233 aligned well with the PI 02 sequence and the intervening sequence between P97 and P102, but the homology ended abruptly at the 3' end of the P97 gene sequence (Fig. 4). The 5' end of pISM1232 showed no homology with the P97 gene or any other known sequence. The 3' end of pISM1233 had homology at the protein level with the Corynebacterium βlutamicum heat-shock protein ClpB (62% identity and 84% similarity in a 98-aa region between aa 158 and 256 of the C. glutamicum sequence). Located upstream of the clpB sequence was the Mhyo triosephosphate isomerase gene tpi (Accession No. L33478). A series of overlapping clones (pISM1165, pISM1168-pISM1170, and pISM1174) with similar restriction maps to pISM1232 and pISM1233 was obtained from the genomic library using a 400- bp probe derived from P102 sequences. The alignment of these clones relative to pISM1232 and pISM1233 is shown in Fig. 4. No sequence information was obtained from these clones, but their restriction maps indicate that they are from the same chromosomal region as pISM1232 and pISM1233. The DNA sequence information obtained from plasmid pISM1234 containing the 4.8-kb hybridizing fragment showed short stretches of DNA homology with PI 02 interspersed with non-homologous regions. Two stretches of 130 bp (82% homology with P102J and 177 bp (95% homology with P102) were identified, as shown in Fig. 5, explaining its weak reaction with the PI 02- specific probe 3. Since clones pISM1232-pISM1234 were not completely sequenced, it is possible that other homologies with PI 02 are present in the cloned fragments that have not been identified. Clone pISM2166 represents an almost completely homologous copy of P102. The 1624-bp sequence shows divergence only in the 144-330 bp (48- 110 aa) region, as can be seen in Figs. 4 and 5. The restriction pattern of PI 02 is almost completely identical to that of the P97 operon sequence, except for the absence of SaH and Accl sites (Fig. 4). SaH is a rare cutting enzyme in Mhyo so the loss of this site in the copy of PI 02 is significant. It is our conclusion that pISM2166 represents a second copy of P102. Plasmids pISM1232 and pISM1233 also show a good alignment with P102 (Fig. 5), but their restriction patterns and the upstream sequences of pISM1232 show that these fragments are derived from a third chromosomal location. Plasmids pISM1232 and pISM1233 are probably from the same chromosomal location, because clones pISM1165, pISM1168-pISM1170 and pISM1174 overlapped the region with identical restriction patterns. Plasmid pISM1234 has only two short stretches of homology to PI 02 recognized by our limited sequence analysis. It is clear, however, that this fragment is derived from another chromosomal region. EXAMPLE 6 Use of the PI 02 Protein in Detecting the Presence of Mycoplasma hyopneumoniae Infection in Swine (Prospective Example) The polypeptides displaying Mycoplasma hyopneumoniae antigenicity of this invention may be used in methods and kits designed to detect the presence of Mycoplasma hyopneumoniae infection in swine herds and therefore to recognize swine in a herd which have been infected by this virus, in order to permit early vaccination of the herd against the infection. For example, the antigens produced by hosts transformed by recombinant DNA molecules of this invention, or antibodies raised against them, can be used in RIA or ELISA for these purposes. In one type of radioimmunoassay, antibody against one or more of the antigens of this invention, raised in a laboratory animal (e.g., rabbits), is attached to a solid phase, for example, the inside of a test tube. Antigen is then added to the tube so as to bind with the antibody. A sample of swine serum, taken from 1 of each 10 to 20 swine per herd, together with a known amount of antigen antibody labeled with a radioactive isotope, such as radioactive iodine, is then added to the tube coated with the antigen-antibody complex. Any antigen (a marker for Mhyo infection) antibody in the swine serum will compete with the labeled antibody for the free binding sites on antigen-antibody complex. Once the serum has been allowed to interact, the excess liquid is removed, the test tube washed, and the amount of radioactivity measured. A positive result, i.e., that the tested swine's serum contains Mhyo antibody, is indicated by a low radioactive count. In one type of ELISA test, a microtiter plate is coated with one or more antigens of this invention and to this is added a sample of swine serum, again, from 1 in every 10 or 20 swine in a herd. After a period of incubation permitting interaction of any antibody present in the serum with the antigen, the plate is washed and a preparation of antigen antibodies, raised in a laboratory animal and linked to an enzyme label, is added, incubated to allow reaction to take place, and the plate is then re washed. Thereafter, enzyme substrate is added to the microtiter plate and incubated for a period of time to allow the enzyme to work on the substrate, and adsorbance of the final preparation is measured. A large change in adsorbance indicates a positive result, i.e., the tested swine serum had antibodies to Mhyo and was infected with that bacteria. EXAMPLE 7 Use of the Antigens and Sequences of This Invention in Vaccines against Mycoplasma hyopneumoniae Infections (Prospective Example) Standard methods known to those skilled in the art may be used in preparing the vaccine of the present invention for aclministration to swine. For example, the polypeptide of choice may be dissolved in sterile saline solution. For long term storage, the polypeptide may be lyophilized and then reconstituted with sterile saline solution shortly before administration. Prior to lyophilization, preservatives and other standard additives such as those to provide bulk, e.g., glycine or sodium chloride, may be added. A compatible adjuvant may also be administered with the vaccine. A vaccine in accordance with this invention can also be prepared using antibodies raised against the polypeptides of this invention in laboratory animals, such as rabbits. This "passive" vaccine can then be administered to swine to protect them from Mhyo infection. Direct incorporation of PI 02 DNA sequences into host cells may also be used to introduce the sequences into animal cells for expression of antigen in vivo. The above description, drawings and examples are only illustrative of preferred embodiments which achieve the objects, features and advantages of the present invention. It is not intended that the present invention be limited to the illustrated embodiments. Any modification of the present invention which comes wit-hin the spirit and scope of the following claims should be considered part of the present invention. What is claimed as new and desired to be protected by Letters Patent of the United States is:

Claims: 1. A protein comprising at least part of the amino acid sequence of PI 02 as shown in Figure 1 and having the antigenicity of native M. hyopneumoniae PI 02. 2. The protein of claim 1, wherein said protein comprises the entire amino acid sequence of PI 02 as shown in Figure 1. 3. A DNA encoding the protein of claim 1 wherein said DNA is a recombinant or a synthetic DNA. 4. The DNA of claim 3, wherein said DNA is operatively linked to at least one control sequence compatible with a suitable bacterial host cell. 5. A bacterial host cell transformed with the DNA of claim 3 which is operatively linked to at least one control sequence compatible with said bacterial host cell, wherein said bacterial host cell is capable of expressing a protein encoded by said DNA in a detectable quantity. 6. A vaccine for protecting a susceptible animal against enzootic pneumonia caused by M. hyopneumoniae comprising an immunogenic protein having the antigenicity of native P102, and a suitable carrier for said immunogenic protein. 7. The vaccine of claim 6, wherein said immunogenic protein has the amino acid sequence shown in Figure 1. 8. The vaccine of claim 6, wherein said immunogenic protein is encoded by the DNA sequence shown in Figure 2. 9. The vaccine of claim 6, wherein said immunogenic protein has an amino acid sequence comprising at least part of the amino acid sequence shown in Figure 1. 10. The vaccine of claim 6, wherein said immunogenic protein is encoded by a DNA having a sequence comprising at least part of the DNA sequence shown in Figure 2. 11. The vaccine of claim 6, wherein said animal is a swine. 12. A DNA for expression in a prokaryotic or eukaryotic host cell of a polypeptide product having the antigenicity of naturally-occurring PI 02. 13. The DNA of claim 12, wherein said DNA is selected from the group consisting of the DNA of Figure 2, the DNAs of Figure 3, the complementary strand of the DNA of Figure 2, and the complementary strands of the DNAs of Figure 3. 14. The DNA of claim 12, wherein said DNA hybridizes with a DNA selected from the group consisting of the DNA of Figure 2, the DNAs of Figure 3, the complementary strand of the DNA of Figure 2, and the complementary strands of the DNAs of Figure 3. 15. A method of protecting an animal against enzootic pneumonia caused by M. hyopneumoniae, comprising: administering to the animal a vaccine comprising an active component selected from the group consisting of a protein which elicits an antibody which recognizes a M. hyopneumoniae PI 02 antigen and a DNA encoding a polypeptide which elicits an antibody which recognizes a M. hyopneumoniae P102 antigen, said vaccine including said active component in an amount effective for protection against enzootic pneumonia caused by M. hyopneumoniae. 16. The method of claim 15, wherein said protein is M. hyopneumoniae PI 02. 17. The method of claim 16, wherein said M. hyopneumoniae PI 02 is of recombinant origin. 18. The method of claim 16, wherein said M. hyopneumoniae P102 is encoded by the DNA sequence of Figure 2. 19. The method of claim 16, wherein said M. hyopneumoniae PI 02 is encoded by a DNA sequence which encodes for at least a portion of the protein having the amino acid sequence of Figure 1. 20. The method of claim 15, wherein said DNA has at least part of the DNA sequence of Figure 2. 21. A method for detecting the presence of PI 02 antibodies in a test sample, comprising the steps of: providing a test sample suspected of containing P102 antibodies; adding a quantity of PI 02 or an antigenic fragment thereof to the test sample, the quantity being sufficient to produce a detectable level of enzymatic activity by anti- Pi 02 antibodies in the test sample; and performing a protein assay to detect the presence of PI 02 antibodies in the test sample. 22. A diagnostic kit for detecting the presence of PI 02 antibodies in a test sample, comprising: a carrier means with at least one container, wherein said at least one container contains labeled PI 02 antigen.

Inventors: HSU TSUNGDA, MINION F CHRIS, HSU, TSUNGDA, MINION, F., CHRIS
Applicants: HSU TSUNGDA, MINION F CHRIS, UNIV IOWA RES FOUND, HSU, TSUNGDA, IOWA STATE UNIVERSITY RESEARCH FOUNDATION, INC., MINION, F., CHRIS
Application year: 1998
Main classification: A61K48
IPC codes: A61K39, A61K48, A61P43, C07K14, C07K16, C12N1, C12N15, C12Q1, G01N33