bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulation of the Immune System by Neisseria meningitidis
Authors: MELANCON‐KAPLAN J. , MURGITA R. A.
Published: June 2006

The immunomoduhitory potential of Neisseria meningitidis was investigated. Spleen cells from mice injected intraperitoneally with low to moderate doses of meningococci (104‐107) were found to display enhanced responses to the mitogens lipopoly saccharide (LPS), phytohaemagglutinin (PHA), and concanavalin A (Con A), In contrast, high doses of meningocoeci (108 109) caused a marked decrease in mitogenic reactivity. Meningococci‐injected mice also displayed a dose‐dependent suppression of a primary anti‐sheep red blood cell (SRBC) plaqueforming cell (PFC) response. The timing between the injection of SRBC and of meningococci appeared to play an important role in the induction of suppression by the organisms. Thus, decreased PFC responses were observed only when the bacteria were injected prior to the antigen. When meningocoeci were injected at the same time or after SRBC, normal or even increased PFC responses developed. Kinetic experiments showed that the onset of suppression of both mitogen and antibody responses by meningoeocci was very rapid, so that by 6‐7 h after injection of the bacteria, mice showed markedly reduced mitogen responses and became essentially unable to mount an antibody response against SRBC. Suppression of mitogen responses was relatively transient, since reactivity returned to normal after 48h. However, the ability of inteclcd animals to mount a normal anti‐SRBC response did not fully return unlil 12 days after the intection. Spleen cells from meningococci‐infected mice also showed markedly depressed PFC responses when stimulated with SRBC in vitro but failed to suppress the response of normal spleen cells in mixed cultures. These observations indicate that putative suppressor cells, if they exist at all. are too insignificant in terms of numbers and/or efficiency to account for the observed immunosuppression. A more likely explanation for the inhibition. which is supported by our data, presented here and elsewhere, is that certain surface components of meningococci are capable of imparting immunosuppressive signals directly onto target lymphocytes.
The Extracellular Portion of HLA‐DR α Chain is Composed of Two Compactly Folded Domains
Authors: BILL P. , LIND P. , RASK L. , PETERSON P. A.
Published: June 2006

A truncated form of the class II antigen DR α chain of the human major histocompatibility complex was produced in bacteria. A cDNA clone encoding the intact chain was modified so that the segment encoding the signal sequence was replaced by an ATG codon and the 3’region downstream to the part corresponding to the third exon was replaced by a stop codon. The new construct was put under the control of the Tac promoter in a bacterial expression vector. The distance between the Shine‐Delgarno sequence and Ihe initialion codon was randomized so that clones with optimal expression of the truncated DR α chain could be obtained after induced expression and immunoscreening. The truncated DR α chain was subjected to limited proteolysis with chymotrypsin. and the resulting cleavage products were analysed by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis. Two fragments were visualized by western blotting. Electrophoresis in the absence and presence of reducing agents suggested that one of Ihe proteolytic fragments contained a disulphide bridge. It is concluded that the extracellular portion of ihe DR α chain is composed of two compactly folded domains connected by an extended stretch of the polypeptide chain.
Idiotype‐Anti‐Idiotype Interactions of VHIX‐Coded Anti‐Progesterone and Anti‐Arsonate Antibodies
Authors: TAUSSIG M. J. , KIRK D. , WANG M.‐W. , ELLIS S. , MEEK K. , MARVEL J. , URBAIN J. , COOMBS R. R. A.
Published: June 2006

The reactivity and specificity of potyctonal and monoclonal anti‐idiotypic antibodies raised against monoclonal anti‐progesterone and anti‐arsonate antibodies have been studied by solid phase radioimmunoassay (RIA) with immobilized idiotype and by passive haemagglutination with idiotype‐coupled red cells. The sensitivity of the two methods was comparable, though some cross‐reactions were only detected by RIA. Passive haemagglutination was found to be especially suitable in screening for monoclonal anti‐idiotypes in hybridoma supernatants and ascites. and had advantages over RIA in detection of syngeneic anti‐idiotypes. Demonstration of binding site‐associated idiotopes was possible by haemagglutination inhibition. RIA and haemagglutination were used to investigate the idiotypic relationships between BALB/c antiprogesterone and anti‐arsonate monoclonal antibodies which share heavy chains encoded by VHIX variable region genes.
Regulation of Carrier‐Specific Response via a Haptenic Epitope
Authors: ZOLLER M. , ANDRIGHETTO G.
Published: June 2006

Influences of haptenic epitopes on the regulation ofcarrier‐specific responses are of importance in vaccination and heterogenization protocols. This situation was modelled by analysing the primary and secondary anti‐horse red blood cell (HRBC) response under the influence of a haptenic epilope (trinitrophenol. TNP). Primary and secondary anti‐HRBC responses were diminished in the presence of TNP. The primary response against the carrier was delayed in the presence of TNP and primary and secondary anti‐carrier responses vanished more rapidly in response to TNP‐HRBC than in response to HRBC. When frequencies of HRBC‐specific B cells were determined under limiting dilution (LD) conditions, a lower frequency of HRBC‐speeific B cells was discovered in the presence of TNP‐HRBC as compared lo HRBC. Accordingly, after priming with HRBC, the frequency of B cells was increased by a factor of 49, while after priming with TNP‐HRBC the frequency was only increased by a factor of 11. Furthermore, haptenic epitopes influenced the anti‐carrier response via regulatory elements. Under physiological conditions, hapten‐specific help was insufficient and hapten‐specific B cells competed for earrier‐specific helper T cells (TH). Suppression was more efficient in hapten‐carrier‐primed mice than in carrier‐primed mice and in line with this observation, an increased frequency of suppressor T cells (Ts) was observed in LD cultures when TNP‐HRBC instead of HRBC were used as antigen. It is concluded that haptenic epitopes are relevant for the anti‐carrier response, since hapten‐specific B cells competc for carrier‐specific help, hapten‐specific suppression down‐regulates carrier‐specific help, and the hapten may hide immunogenie epitopes of the carrier, resulting in incomplete activation of the B‐cell repertoire.
Trinitrobenzenesulphonic Acid‐Induced Unresponsiveness at the Systemic Level
Authors: ANDRIGHETTO G. , ZÖLLER M.
Published: June 2006

To investigate the mechanism underlying B‐cell tolerance, which is still discussed as being the consequence of (functional) clonal deletion or suppression, limiting dilution (LD) analysis of the frequencies of B cells as well as regulatory cells after tolerance induction with trinitrobenzenesulphonic acid (TNBS) was performed. It was shown that the frequency of functionally active hapten‐specific B cells was decreased to less than 10% of the frequency in untreated BALB/c mice. After an immunogenic challenge, trinitrophenyl (TNP)‐specific B cells of tolerized mice expanded, but did not reach the level of TNP‐specific B cells in untreated mice. The expansion of TNP‐specific B cells in TNBS‐tolerized mice after challenge with TNP‐horse red blood cells (HRBC) as observed in LD cultures was in contrast to the absence of anli‐ TNP plaque‐forming cells (PFC) in freshly harvested spleen cells (SC) and the non‐detectability of anti‐TNP antibodies (AB). Henee, the functional deletion (=anergy) of B cells in vivo appears to be sustained by regulatory cells. Analysis of the regulatory compartment revealed that tolerance induction resulted in transient augmentation of TNP‐specific helper T cells(TH), continuously elevated levels of suppressor T cells (TS), and a low level of contrasuppressor T cells (TCS). But, contrary to non‐tolerized mice, TCS, of tolerized mice were rather refractory to stimulation with TNP‐HRBC. Hence, we would like to hypothesize that clonal anergy of B cells leads to inappropriate activation of TCS, whose nominal antigens are antibodies. This in turn sustains the persistence of high levels of TS, i.e. tolerance would be maintained by interruption of feedback activation of regulatory cells via effector cells/molecules.
Biological Activity in Sensitized Guinea Pigs of MPB 70, a Protein Specific for Some Strains of Mycobacterium bovis BCG
Authors: HASLØV K. , ANDERSEN Å. B. , BENTZON M. W.
Published: June 2006

MPB 70 is a protein found in large quantities in the culture filtrate (CF) of the Tokyo and some other strains of Mycobacterium bovis BCG, and it has a remarkable degree of specificity for these strains. We estimated the molecular weight of MPB 70 to 22,000 by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE). SDS‐PAGE and immunoblotting showed that MPB 70 was present in high quantities in CF from BCG Tokyo, that it could be also demonstrated in BCG Copenhagen, and that it was absent in CF from M. tuberculosis H37Rv. When the purified MPB 70 preparation used in the present study was run in SDS‐PAGE, blotted and stained with a polyclonal rabbit or a monoclonal mouse anti‐MPB 70 antibody, several bands in addition to the main 22 kDa band were seen, indicating a tendency of the MPB 70 molecules and/or fragments thereof to form very stable aggregates with themselves. The biological activity of MPB 70 was studied in groups of guinea pigs sensitized with live BCG of the Tokyo and Copenhagen strains, Guinea pigs from both groups developed reactivity to tuberculin PPD as assessed by skin tests and lymphocyte stimulation tests with peripheral blood or lymph node lymphocytes. In addition, a strong and persistent reactivity to MPB 70 was demonstrated in the BCG Tokyo group with both methods. Guinea pigs sensitized with the Copenhagen strain were only weakly reactive to MPB 70. Skin reactions in guinea pigs that had been repeatedly tested with MPB 70 and tuberculin were compared with reactions in animals tested only once. Reactions to MPB 70 in BCG Tokyo sensitized guinea pigs were suppressed by repeated tests, whereas tuberculin reactions were boosted by the interim tests. The levels of specific anti‐MPB 70 antibodies were higher in BCG Tokyo‐ than in BCG Copenhagensensitized guinea pigs. MPB 70 has a high degree of specificity and is a strongly immunogenic protein, which may prove useful in studies of mycobacterial immunology.
Two M315 Idiotopes Defined by Isologous Monoclonal Antibodies: One Depends on Germline and the Other on Mutated Murine λ Light Chain Sequences
Authors: KRISTOFFERSEN G. , HANNESTAD K. , HANSEN T.
Published: June 2006

We have previously reported that T helper cells of BALB/c mice recognize the unique mutated sequence Phe91, Arg95, Asn96 of the λ2 L chain of isologous (BALB/c) myeloma protein 315. Here we study two Id(Id‐315.1.4 and Id‐315.TH) of the DNP‐Lys binding M315 defined by two monoclonal isologous anti‐Id Ab (Ab 2‐1.4 and Ab 2‐TH). Both Id were (1) totally expressed by Fv‐315, but not by free unpaired V domains, (2) specifically dependent on VH, since λ2‐315 recombined with four other H chains did not express the Id, (3) related to the haptenbinding site because their expression was blocked by the haptens DNP‐Lys and DNP‐Gly, and (4) topographically related because Ab 2‐1.4 and Ab 2‐TH competed with each other for binding to M315. The contribution of λ chain V regions was studied with the aid of reconstituted Ig molecules of H‐315 paired with λ1, λ2, and #LD3 L chains. Id‐315. TH was expressed equally well by reconstituted Ig containing three different λ2 chains (λ2‐5‐7, λ‐T952, and λ2‐315), but its expression was profoundly reduced when H‐315 was associated with #LD‐SAPC15 or #LD2‐T952 differ from λ2‐315 at positions 38, 94, 95, 96, and 98 or 99, respectively, Id‐315.1.4 probably requires the unique mutated amino acids Phe94, Arg95, Asn96 of λ2‐315. This resembles the effects on Id expression of previously reported unique amino acids of the D region. We failed to confirm that hyperimmunization of BALB/c mice with Ab 2‐1.4 cross‐linked to KLH induced M315‐like Ab. The results are discussed in terms of the contribution of the third bypervariable loop of λ chains to Id and the immunogenicity of isologous Ig.
Expression of Major Histocompatibility Complex Class II Subregion Products by Jejunal Epithelium in Patients with Coeliac Disease
Authors: SCOTT H. , SOLLID L. M. , FAUSA O. , BRANDTZAEG P. , THORSBY E.
Published: June 2006

The MHC class II subregion product (HLA‐DR), HLA‐DP, and HLA‐DQ) were located by immunofluorescence in serial sections of ethanol‐fixed, paraffin‐embedded jejunal mucosa from control subjects and patients with coeliac disease (CD). DR staining was seen in a granular luminal distribution and basolaterally on surface epithelial was positive for DR almost to the bottom of the glands. This contrasted with virtually absent glandular DR standing in controls and weak staining including only the upper part of the crypts in 5 out of 11 treated patients. HLA‐DQ appeared only in three untreated patients and was restricted to patches of surface epithelium. The number of intraepithelial T lymphocytes per millimetre of surface epithelium was significantly higher in untreated than in treated CD patients or controls; it was also significantly higher in specimens with epithelial DP expression than in those without. This suggested that intraepithelial lymphocytes modulate epithelial class II expression.
Idiotypic Network in Myasthenia Gravis Demonstrated by Human Monoclonal B‐Cell Lines
Authors: LEFVERT A. K. , HOLM G.
Published: June 2006

Human monoclonal anti‐receptor and anti‐idiotypic antibodies were obtained from EpsteinBarr virus‐transformed lymphoblastoid cells of patients with myasthenia gravis. The majority of antibodies (85/117) were IgM, and all IgM antibodies had lambda light chains. A marked restriction to one recurrent idiotype was found, despite the additional presence of other idiotypes in the serum from all patients. The presence of idiotypes and anti‐idiotypes in the same patient was verified by the demonstration of specific complex formation between an antireceptor antibody and an anti‐idiotypic antibody produced by two different clones. Studies of human monoclonal antibodies produced by lymphoblastoid cell lines provide important information about the B‐cell repertoire in myasthenia gravis and demonstrate a basis for a functional antibody network in this disease.
Specific Deposition of Serum Amyloid A Protein 2 in the Mouse
Authors: SHIROO M. , KAWAHARA E. , NAKANISHI I. , MIGITA S.
Published: June 2006

The homogenates of amyloid‐laden spleens prepared from CBA mice were analysed by SDS‐PAGE and immunoblotting employing rat anti‐murine monoclonal antibody, MSA 4–26, The results showed that the precursor of amyloid A protein (AA). serum amyloid A protein 2 (SAA2). and SAA intermediates with molecular weights of 10,000, 9000, and 8000 were contained in amyloid‐laden tissues. The experiment using sonicated spleen cells and acute phase murine sera showed a delay in the degradation rate of SAA2 on cell fragments and the remains of SAAI in supernatants. This result can explain disappearance of SAA2 from the murine serum during amyloidogenesis in vivo.
Responsiveness in Diffuse versus Local Cutaneous Leishmaniasis is Due to Parasite Differences
Authors: AKUFFO H. , SCHURR E. , ANDERSSON G. , YAMANEBERHAN T. , BRITTON S.
Published: June 2006

Leishmania aethiopica infection results in two main clinical entities, diffuse disease (DCL) and localized ulcers (LCL). The lack of reactivity to leishmanial antigens has been attributed, among other things, to some inherent immunological defect of the host or considered as a consequence of the initial site of infection. Properties unique to the infecting parasite have been said to contribute little if anything to the differences between DCL and LCL found in the same areas of Ethiopia. Data are given to show that infected individuals respond by higher production of IL‐2 to antigens from LCL isolates (Icl antigen), than to antigens derived from DCL isolates (dcl antigen). Furthermore, dcl antigen induced less gamma interferon from lymphocytes of all individuals tested than did lcl antigen. Lymphocytic proliferation of cells from control individuals working in the endemic area was higher in response to lcl isolates than to del isolates. These findings suggest that some differences in the parasites may contribute to the clinical outcome of infection with L. aethiopica.
Identification of Linear HLA Class II Amino Acid Sequences Recognized by Rabbit Antisera against Native Molecules
Authors: CHERSI A. , MORGANTI M. C. , HOUGHTEN R. , CHILLEMI F. , MURATTI E.
Published: June 2006

A rabbit was immunized with B lymphoblastoid cells, and subsets of the antibodies produced were isolated on affinity columns made from synthetic peptides corresponding to known amino acid sequences from the human class II antigens DQ and DP. Those peptides for which specific antibodies were isolated could be assumed to contribute to the antigenic properties of the intact antigen. The antibody subsets were tested for binding to synthetic peptides, to glycoprotein fractions isolated from cells with different DR and DQ specificities, and to the cells used for immunization of the rabbit. The isolation of those antibodies directed against well‐defined amino acid stretches of the histocompatibility antigens is proof of the role of those regions in determining the antigenic properties of these molecules.
Functional and Phenotypical Characterization of Activated T Cells from Intra‐articular Sites in Inflammatory Joint Diseases
Authors: JAHN B. , BURMESTER G. R. , STOCK P. , ROHWER P. , KALDEN J. R.
Published: June 2006

The presence of activated T lymphocytes bearing interleukin 2 (IL‐2) receptors and HLA class II (la) antigens accompanied by impaired T cell functions such as a decreased mitogenic responsiveness are characteristic findings, especially in intra‐articular sites in chronic inflammatory joint diseases. The objective of the present study was to further characterize these in vivo activated T cells by the investigation of IL‐2 production and a possible T cell receptor modulation. IL‐2 receptors were found to tic expressed primarily in ihe CD4+ subset. The Ia+ subset expressing both DR and DQ antigens showed a weaker miiogen‐induced response as compared to the la+ fraction. A decreased mitogen‐induced IL‐2 production and a lower response to anti‐CD3 monoclonal antibodies was observed with synovial T lymphocytes as compared to peripheral blood T cells. The density of the CD3 molecule, known to be closely associated with the T cell receptor, was significantly lower in intra‐articular sites, while other T cell‐specific surface molecules were expressed to a similar extent in both compartments. The decreased synovial T cell mitogenesis was not restored by the addition of lymphokines (IL‐1 and IL‐2) or blood monocytes, nor by removing CD8+ T cells. These data present further evidence for a significant T cell activation in intra‐articular sites in chronic inflammatory joint diseases. The decreased expression of the CD3 glycoprotein suggests a modulation by so far unidentified antigen(s), which could also be responsible for the weak T cell response elicited by polyclonal mitogens.
The Amino Acid Sequence of Serum Amyloid A (SAA) Protein in Mink
Authors: SYVERSEN V. , SLETTEN K. , MARHAUG G. , HUSBY G. , LIUM B.
Published: June 2006

The amino acid sequence of serum amyloid A (SAA) protein from mink was established by characterization of peptides derived from digestion of the protein with trypsin and from cleavage with BNPS‐skatole. In three positions, two amino acid residues were found, showing that the protein is polymorphic, tn position 10 both valine and isoleucine were found, while only valine was observed in protein AA. Prominent sequence homologies with protein SAA and protein AA from other species were seen, particularly corresponding to the segment between positions 31 and 54, but also in the C‐terminal part of protein SAA, which is not shared by protein AA.
Low Degree of DNA Polymorphism in the HLA‐Linked Lymphotoxin (Tumour Necrosis Factor β) Gene
Authors: PARTANEN J. , KOSKIMIES S.
Published: June 2006

Tumour necrosis factors (TNF) α (cachectin) and β (lymphotoxin) are lymphokines with many biological activities. For example, the molecules regulate the immune system, which is of special interest since the genes for the TNF are located within the human major histocompatibility complex (MHC). The MHC encodes HLA‐molecules that play a critical role in the cellular interactions of the immune response. To test whether genetic polymorphism in the TNF genes may be involved in the associations between HLA and autoimmune diseases, we here describe an analysis of DNA polymorphism in the human TNF‐β gene. The results show that the TNF‐β gene has only a low degree of DNA polymorphism, and that this is not associated with HLA antigens showing a strong association with autoimmune‐like diseases.
Up‐regulation of the Expression of Secretory Component and HLA Molecules in a Human Colonic Cell Line by Tumour Necrosis Factor‐α and Gamma Interferon
Authors: KVALE D. , BRANDTZAEG P. , LØVHAUG D.
Published: June 2006

Secretory component (SC) acts as receptor for polymeric IgA (pIgA) and pIgM on the basolateral face of secretory epithelia. This study showed that both the production and surface membrane expression of SC were additively up‐regulated by tumour necrosis factor‐α (TNF) and gamma inferreron (IFN‐γ) in a human colonic cell line (HT‐29m2). TNF likewise enhanced membrane expression of HLA class I determinants. Moreover, TNF augmented synergistically the IFN‐induced dc novo synthesis of HLA class II (DR) molecules. These data suggest that there are different regulatory mechanisms for the action of TNF and IFN and for the expression of HLA‐DR and SC/HLA class I. Addition of actinomycin D abolished the cytokine‐mediated increase of SC synthesis and expression. This observation suggested that transcriptional events are required for the cytokine‐mediated up‐regulation of SC.
Detection of IgA Antibodies and Quantification of IgA Antibody‐Producing Cells Specific for Ovalbumin or Trichinella spiralis in the Rat
Authors: VAN LOVEREN H. , OSTERHAUS A. D. M. E. , NAGEL J. , SCHUURMAN H. J. , VOS J. G.
Published: June 2006

This report describes procedures to quantify IgA responses in the rat sensitized to ovalbumin or infected with the parasite Trichinella spiralis: an ELISPOT detecting specific IgA antibody producing cells in lymph nodes, and an ELISA demonstrating IgA antibody in scrum and gut mucosal scrapings. For this purpose a mouse monoclonal anti‐rat IgA antibody was produced. This IgG1‐κ1 antibody recognized rat IgA but not rat IgM, IgG, or IgE. It proved very suitable in both assays. Using this reagent we could demonstrate large numbers of IgA anti‐ovalbumin‐producing cells in the mesenteric lymph nodes is 15.days after sensitization to ovalbumin via the Peyer's patches. At 28 days after sensitization the numbers were much lower. IgA antibody titres to ovalbumin in serum were maximal between days 14 and 21 after immunization. Maximal numbers of IgA anti‐T. spiralis‐producing cells were found in the mesenteric lymph nodes 12 days after infection with muscle larvae, followed by a sharp decrease at 15 days. Maximal IgA anti‐T spiralis antibody titres in serum and mucus scrapings of small intestines were found on days 10 and 12 after oral infection with the parasite
Ligand‐Specific Cross‐Inhibition of Monocyte Phagocytosis
Authors: KÁVAI M. , SÁNDOR M. , SZEGEDI GY. , GERGELY J.
Published: June 2006

Human monocytes exposed to particles reacting with receptors of one specific type demonstrate a markedly reduced phagocytosis of particles reacting of the receptors of another type. The phagocytosis of yeast particles (Saccharomyces cerevisiae) coated with C3 fragments and of uncoated ones by monocytes can inhibit the subsequent endocytosis of sheep erythrocytes sensitized with IgG antibody and vice versa. The erythrocytes were labelled with 51Cr and the yeast particles with 125I. The dependence of the receptor‐ligand reaction on temperature and time of preincubation, as well as on ratio of cell and particle, suggests that this cross‐inhibition may be associated with plasma membrane modulations beginning with the attachment of ligands to a receptor and followed by their endocytosis. The differences between the functions of temperature, time, and concentration in inhibition caused by different receptor‐ligand reactions suggest that these membrane modulations are probably ligand‐specific processes.
On the Interaction of the First Complement Component C1 and its Subunit Clq with Solid‐Phase IgM Immune Complexes
Authors: WEINER E. M.
Published: June 2006

The interaction of C1 and C1q with solid‐phase anti‐dextran MOPC‐104E IgM was studied. An enzyme‐linked immunosorbent assay (ELISA) was used to detect bound C1q. The results revealed that immobilized IgM Is converted to the Functionally active ‘staple’ conformation by the specific polyvalent ligand dextran (B 1355/S). C1q is, fixed to IgM dependent on the antigen concentration, and its binding might be explained by assuming a functional binding constant (K) of approximately 109m−1. Molecules bound with a K in the range of 107m−1 cannot be detected by this ELISA procedure. The fixation of C1q saturated with an excess of the C1r2S2‐tetramer differs from that of free C1q. C1q incorporated in the C1 complex rapidly dissociates independently of the antigen concentration. Since the complement binding sites are located at definite positions on the IgM molecule because of its pentameric Structure, it is suggested that the distinguishable association properties of C1 and C1q are brought about from the altered flexibility of the C1q molecule complexed with C1r2s2.
Induction of CD43 Expression during Activation and Terminal Differentiation of Human B Cells
Authors: WIKÉN M. , BJÖRCK P. , AXELSSON B. , PERLMANN P.
Published: June 2006

Only a small population (25–30%) of human peripheral blood B lymphocytes expresses large sialoglycoprotein (LSGP) (CD43). However, in the presence of autologous T cells and pokeweed mitogen (PWM) a majority (50–90%) of the immunoglobulin‐producing cells (cÍg+ cells) that develop from these B cells express CD43 is detected with anti‐CD43 monoclonal antibodies (MoAb) B1B6, and the proportion of CD43+cIg+ cells increases with time of culture. Furthermore, a relatively larger proportion (60–80%) of the IgG‐producing cIg+ cells are CD43+ compared with IgM‐containing cIg+ cells (30–50%). In human tonsils, signficantly more CD43+ cells (35%) are found in the in vivo‐activated fraction of B cells than in the fraction of resting B cells (5%). A majority of the cIg+ cells that develop from the resting or the in vivo‐activated tonsillar B cells in a PWM‐induced B‐cell differentiation system are CD43+ (80–100%). Furthermore, tonsillar B cells depleted of CD43+ cells give rise to cIg+ cells, of which the majority are CD43+, and the proportion of such cells increases with time of culture (60–90%). Taken together, these results indicate that LSGP belongs to a group of B‐cell membrane molecules that are induced and upregulated upon activation and differentiation.
Human Antibody Responses to Two Conjugate Vaccines of Haemophilus influenzae Type B Saccharides and Diphtheria Toxin
Authors: SEPPÄLÄ I. , SARVAS H. , MÄKELÄ O. , MATTILA P. , ESKOLA J. , KÄYHTY H.
Published: June 2006

Antigenicity of two Haemophilus influenzae type b (Hib) conjugate vaccines was studied by immunizing adults and 2‐year‐old children. Both vaccines induced strong anti‐Hib responses and strong antibody responses to diphtheria toxin (DT), the protein part of the conjugate. The adults' responses were stronger than the children's. A conjugate of Hib oligosaccharide and mutant diphtheria toxin (HbOC) emerged as slightly superior to a conjugate of Hib polysaccharide and diphtheria toxoid (PRP‐D). HbOC induced somewhat higher total anti‐Hib responses and significantly higher IgG1 anti‐Hib responses than PRP‐D. IgG1 and IgG2 were the main IgG subclasses of the anti‐Hib antibodies, whereas IgG1 and IgG4 were the main subclasses of the anti‐DT antibodies. Within this main rule, the ratio IgG1/IgG2 of anti‐Hib antibodies varied between individuals. The average ratio was higher than five in children but approximately one in adults. It was lower in adult recipients of the polysaccharide conjugate (0.69) than in adult recipients of the oligosaccharide conjugate (1.55). A large interindividual variation was observed in concentrations of IgG2 of Hib specificity, perhaps reflecting a small number of IgG2‐committed B‐cell clones participating in the response.
Different Origins of IgA Antibodies with Various Antigen Specificities Appearing in Rat Bile
Authors: NILSSON K. , DAHLGREN U. I. H. , HANSON L. Å.
Published: June 2006

Eight lactating and seven non‐lactating female rats were immunized in Peyer's patches (Pp) with Escherichia coli 06 carrying type 1 pili. Eight days later the thoracic duct was drained and bile was collected at the same time. During the lymph drainage in the lactating rats, the biliary IgA anti‐pili antibodies decreased less than the anti‐lipopolysaccharide (LPS) antibodies. The non‐lactating rats showed only a very small difference in decrease between the anti‐pili and the anti‐LPS antibodies. Transfer of mesenteric lymph node cells from male donor rats immunized with the E. coli strain to syngeneic male recipients resulted in the appearance of both IgA anti‐pili and anti‐LPS antibodies in the bile. This is at variance with the results seen in lactating rats, where only biliary IgA anti‐LPS is seen after similar cell transfer. In conclusion, the study shows that in lactating rats a larger proportion of biliary IgA anti‐pili antibodies than anti‐LPS antibodies is derived from extraintestinal sites, such as the mammary glands or the liver. Thus, this study confirms that the nature of the antigen influences the transfer of the secretory antibody response to different secretions.
Immune Response in Deep Cervical Lymph Nodes and Spleen in the Mouse after Antigen Deposition in Different Intracerebral Sites
Authors: WIDNER H. , MÖLLER G. , JOHANSSON B. B.
Published: June 2006

Brain interstitial and cerebrospinal fluid drainage into the lymphatics was studied by injections of 5μl of packed sheep red blood cells (SRBC) injected into the caudate nucleus, the occipital lobe, and the lateral ventricle of the brain in mice. The number of plaque‐forming cells (PFC) was determined in the deep cervical lymph nodes, the axillar lymph nodes, and the spleen, and the number of PFC was compared with the response in the same tissues after Intravenous immunization with 0.1 ml 10% SRBC. The weight of the deep cervical lymph nodes increased 3.0 times on day 3 after injection in the brain parenchyma compared with the weight of these nodes after intravenous immunization. The antigen‐specific response peaked on day 5, 392±37 PFC/106 for IgG in the deep cervical lymph nodes after antigen deposition in the caudate nucleus, whereas only a minor peak in the antigen‐specific response was obtained after intraventricular antigen deposition, 127±79 PFC×106 for IgG on day 6. There were no increased PFC in any of the lymph nodes after intravenous immunization. The experiments show an antigen‐specific response in the deep cervical lymph nodes after intracerebral antigen deposition, whereas antigens deposited in the lateral ventricles drain preferentially to the blood, with a high response in the spleen.
Generation of High‐Rate Ovalbumin‐Specific Antibody‐Secreting Cells in Cultures of Human Peripheral Blood B Cells Obtained from Non‐Immunized Blood Donors
Authors: HART L. A.‘t , ZIJLSTRA J. , HEIJNEN J. J. , BALLIEUX R. E.
Published: June 2006

When human peripheral him id B cells are cultured for 6 days with the T cell‐dependent peptide antigen ovalbumin (OA) in the presence of antigen‐presenting cells and helper T cells, plaque‐forming cells (PFC) are generated. These OA‐induced PFC differ from the conventional high‐rate antibody‐secreting PFC formed after stimulation of B cells with recall antigens (e.g. tetanus toxoid) in that they secrete antibody at a very low level. Previous studies have shown that OA‐induced PFC are B lymphocytes in an early activation stale rather than cells that have differentiated into plasmablasts. The apparent arrest in the maturation of OA‐induced PFC in an early activation phase can he overcome by simultaneous stimulation with interleukin 2 (1L‐2) and gamma interferon (IFN‐γ). The isotype of the OA‐specific antibodies secreted, however, are only of the IgM class, demonstrating that an isotype switch docs not occur.
Association between HLA‐DR2 and Production of Tumour Necrosis Factor α and Interleukin 1 by Mononuclear Cells Activated by Lipopolysaccharide
Authors: BENDTZEN K. , MORLING N. , FOMSGAARD A. , SVENSON M. , JAKOBSEN B. , ØDUM N. , SVEJGAARD A.
Published: June 2006

The production of tumour necrosis factor (TNF) and interleukin 1 (IL‐1) by lipopolysaccharide‐activated mononuclear cells from 39 healthy donors was studied in vitro by bioassay and ELISA. The donors were typed for HLA‐A, ‐B, ‐C, ‐DR, and ‐DP antigens. There was no detectable production of TNFβ (lymphotoxin). The intracellular levels of bioactive TNFα were minimal or undetectable in all cases. Cells from HLA‐DR2+ individuals secreted significantly lower amounts of TNFα than cells from HLA‐DR2− donors [2 ng/ml (1.5–4.4) and 7.5 ng/ml (3.9–8.3) respectively (medians 25–75%); P<0.01]. The difference disappeared if the cells were preactivated for 2 days with 1000 U/ml of recombinant gamma interferon (rIFN‐γ). In some individuals, the TNFα response increased considerably after IFN‐γ priming, in particular in those possessing the HLA‐DR2 antigen. In contrast, there was no detectable difference in the production of IL‐1β between the donors, and the IL‐1β response decreased significantly after rIFN‐γ priming in HLA‐DR2+ individuals [2.3 ng/ml (1.1–8.4) versus 7.2 ng/ml (5–7.9); P<0.05] and in HLA‐DR2− individuals [3 ng/ml (1.1–5.3) versus 5.7 ng/ml (3.9–7.5); P<0.01]. There was no correlation between the TNFα and IL‐1 responses and any of the other HLA‐DR, ‐DP, or ‐B antigens. There was a significant positive correlation between the levels of TNFα measured by ELISA and by cytotoxicity assay. However, the TNFα‐containing supernatants from 9 out of 37 individuals appeared to contain inhibitor(s) of the biological activity of TNFα. The presence of inhibitor(s) was not associated with any HLA antigens.
Effective Inhibition of Cardiolipin‐Binding Antibodies in Gram‐Negative Infections by Bacterial Lipopolysaccharide
Authors: VAARALA O. , VAARA M. , PALOSUO T.
Published: June 2006

Anticardiolipin antibodies (ACA) were detected by solid‐phase enzyme immunoassay in the majority of sera from patients with Gram‐positive and Gram‐negative bacterial infections. The response involved all the major immunoglobulin classes IgG, IgM, and IgA. The specificity of the ACA was studied in competitive inhibition experiments with three putative antigens: cardiolipin, lipopolysaccharide (LPS) isolated from Salmonella minnesota, strain Re 595, and synthetic Escherichia coli lipid A. The binding of IgG class ACA from the sera of five patients with Gram‐negative infections was effectively inhibited by LPS, whereas 100‐fold more cardiolipin was required for comparable inhibition. Pure lipid A was a less effective inhibitor of anti‐cardiolipia activity than LPS. This pattern of reactivity was not seen in sera from patients with Gram‐positive infections, syphilis, or systemic lupus erythematosus. Our findings suggests that cardiolipin may not be the inducing antigen for the cardiolipin‐binding antibodies that develop in Gram‐negative infections.
High‐Density Lipoprotein has Different Binding Capacity for Different Apoproteins
Authors: HUSEBEKK A. , SKOGEN B. , HUSBY G.
Published: June 2006

Purified human amyloid protein A (AA) or serum amyloid protein A (SAA) was incubated with normal human high‐density lipoprotein (HDL). After ultracentrifugation the amount of AA or SAA associated with HDL was measured. It was found that the binding capacity of HDL for SAA was higher than that for AA. Incubation of these in vitro associated HDL‐AA and HDL‐SAA complexes with purified apo AI or apo AII resulted in varying degrees of displace‐ment of the associated AA or SAA from HDL. Under the experimental conditions used, apo AI was able to displace AA from HDL, while apo AII was able to displace both SAA and AA. This indicates that the binding capacity of HDL is different for SAA and AA Mouse acute‐phase HDL was isolated and the native complexes were incubated with human apo AII SAA2, the amyloidogenic SAA variant in mice, was displaced from HDL to a greater extent than SAA1, indicating a lower binding capacity for the amyloidogenic SAA variant for the HDL complexes.
T‐Cell Response to Purified Protein Derivative after Removal of Langerhans' Cells from Epidermal Cell Suspensions Containing Keratinocytes Expressing Class II Transplantation Antigens
Authors: TJERNLUND U. , SCHEYNIUS A. , JOHANSSON C. , HAGFORSEN E. , NILSSON H.
Published: June 2006

In a previous study we observed that human epidermal cell (EC) suspensions containing HLA‐DR‐expressing keratinocytes showed an amplified T‐cell response to purified protein derivative (PPD). To evaluate further the possible immunological importance of class II transplantation antigens on keratinocytes we have compared the T‐cell response to PPD in the presence of the following stimulator cells: EC suspensions from normal skin, or EC from tuberculin‐reactive skin with or without removal of Langerhans' cells. The proliferation of purified T lymphocytes from peripheral blood in response to PPD in the presence of various concentrations of autologous EC was measured by [3H]thymidine incorporation on day 6. In 3 experiments out of 4 the EC from tuberculin‐reactive skin, containing 28–76% HLA‐DR‐expressing cells as judged by immunocytochemistry (which also revealed fairly numerous HLA‐DQ/ ‐DP‐expressing keratinocytes and a slight increase in CD36‐ and CD4‐ but not CD1‐expressing cells), induced a more pronounced T‐cell response to PPD than did normal EC. This was not the case in the fourth experiment, in which a small number of HLA‐DR‐ (15%) and few if any HLA‐DQ‐/‐DP‐expressing keratinocytes were found. Immunomagnetic removal of CD1‐reactive Langerhans' cells from the tuberculin‐reactive EC suspensions resulted in a reduction of the T‐cell response to PPD, in most cases down to background level (T cells alone + PPD). This study does not support the hypothesis that HLA‐DR‐expressing keratinocytes can in themselves act as antigen‐presenting cells.
Increased Susceptibility of Periodate‐Treated Tumour Cells to Human but Not to Mouse or Rat Natural Killer Cells
Authors: AXBERG I.
Published: June 2006

Treatment of intact cells in the cold with low concentrations (1 mM) of sodium meta periodate (PI) selectively oxidizes the surface‐exposed sialic acid residues to the corresponding aldehydes. Such treated tumour cells show greatly enhanced sensitivity to lysis by fresh human NK cells but not to mouse or rat NK cells. Reduction of the PI‐treated cells with sodium borohydride (NaBH4) reduced their NK sensitivity to that of untreated cells. In target conjugate formation assays PI‐treated tumour cells displayed a higher binding capacity than control cells or PI + NaBH4‐treated cells to both mouse and human effector cells. Neuraminidase treatment of K562 and Molt‐4 increased target susceptibility to human NK cells but not to mouse, whereas the susceptibility of Yac‐1 cells was left unchanged using both human and mouse effector cells. The same pattern of reactivity is shown in the target binding assay. These findings indicate that Subtle molecular changes in the surface‐exposed carbohydrates of target cells might have a fundamental impact on their sensitivity to lysis by NK cells from certain species, and that in cross species effector‐target combinations a higher binding capacity is not sufficient for increased lysis to occur.
Identification of αβ and γδ T Cell Receptor‐Positive Cells
Authors: GEISLER C. , LARSEN J. K. , PLESNER T.
Published: June 2006

Two lineages of T lymphocytes bearing the CD3 antigen can be defined on the basis of the nature of the heterodimeric receptor chain (αβ or γδ T cell receptor (TCR)) expressed. Precise identification of αβ and γδ TCR+ cells is essential when studying the tissue distribution and function of these different T ceils. In immunofluorescence studies γδ TCR− cells have been identified as CD3+ WT‐31 or CD3+CD4− CD8− cells. However, this may not be the optimal procedure because γδ TCR+ cells are weakly WT‐31+, and some are CD8+. The aim of this study was to evaluate a panel of monoclonal antibodies (MoAb) directed against different chains of the TCR‐T3 complex for a more precise identification of αβ+ and γδ TCR+ cells in flow cytometric studies. We found that the MoAb anti‐Ti‐γA and δ‐TCS‐1, recognizing the TCR‐γ and the TCR‐δ chain respectively, only reacted with a subpopulation of γδ TCR+ cells, whereas another TCR‐γ chain recognizing MoAb anti‐TCR‐δ1 reacted with all γδ TCR+ cells. All MoAb reported to belong to the CD3 group reacted with both αβ TCR+ and γδ TCR+ cells as expected. Our results indicate that all γδ TCR+ cells can be identified with the MoAb anti‐TCR‐δ1. Because no MoAb recognizing the TCR‐α or TCR‐β chains at the cell surface of intact cells are yet available, we suggest that αβ TCR+ cells could be identified as CD3+ anti‐TCR‐δ1− cells.
Tolerogen‐Mediated Suppression of the Immune Response
Authors: DINTZIS R. Z. , MIDDLETON M. H. , DINTZIS H. M.
Published: June 2006

The anti‐dinitro‐phenyl (Dnp)IgM antibody response in mice was inhibited by administration of either a non‐immunogenic form of Dnp‐polyacrylamide (Dnp‐Pa) or an excess amount of an immunogenic form of Dnp–Pa. Spleen cells, alive or heat‐killed, from mice tolerized in vivo by either method, inhibited the anti‐Dnp response of naive spleen cells co‐cultured in vitro with antigen. Conversely, donor cells tolerized in vivo by a high dose of immunogenic Dnp–Pa, when titrated into a naive cell culture which contained no antigen, produced a stimulatory dose‐response curve. Both the dose‐dependent inhibition and stimulation correlated strongly with the amount of 125I‐labelled Dnp–Pa carried over by tolerized spleen cells into the naive cell culture system. Because the doses and experimental procedures used were comparable to those commonly used for suppressor cell generation and assay, it is suggested that antigen‐specific suppressor cells may produce their effects through passive transfer of antigen and/or tolerogen.
The Isolation of Human Lung Mast Cells by Affinity Chromatography
Authors: VAN OVERVELD F. J. , TERPSTRA G. K. , BRUIJNZEEL P. L. B. , RAAIJMAKERS J. A. M. , KREUKNIET J.
Published: June 2006

A method of isolation has. been developed to purify mast cells from human lung tissue. The purification steps are: (1) dispersion of human lung tissue in single‐cell suspensions by enzymatic digestion, (2) partial purification by counterflow centrifugal elutriation, (3) Percoll gradient centrifugation, and (4) enrichment of the mast cells by affinity chromatography using anti‐human IgE‐Sepharose. Enzymatic dispersion yielded 0.6±0.2×106 mast cells per gram wet tissue with purities of 3.3±1.0% (mean ±SIM n=3). Elutriation and gradient centrifugation yielded 0.36±0.05×10% mast cells per gram lung tissue in fractions with purities of 30.8±10.7%. Enriched mast cell Fractions were combined, and disposed of contaminating cells by affinity chromatography, thereby yielding 0.25±0.03×106 mast cells per gram lung tissue, and improving the purity to 75.3±8.3%. The purified mast cells were intact and vitality exceeded this way from 1 g wet lung tissue 0.25±0.03×106 mast cells may be isolated with a mean recovery of 41.7±2.4% and a mean purity of 75.3±8.3%.
Functional Properties of Neoplastic T Cells in Helper T Cell Prolymphocytic Leukaemia with IgM Hypergammaglobulinaemia
Authors: RAZIUDDIN S. , SHEIKHA A. I. , KHAN A. R. , LATIF A. B. A.
Published: June 2006

A case of T cell prolymphocytic leukaemia of helper/inducer T cell phenotype with IgM hypergammaglobulinaemia in a 65‐year‐old Saudi man is presented. The neoplastic T cells in the patient had an OKT3+, OKT4+, OKT8−, OKT11+, OKCLL+, OKIa1+, OKDR+, Tac+ phenotype. The presence of OKIa1+, OKDR+, and Tac+ antigens indicates that the leukaemic T cells were in an activated state. The cells responded to phytohaemagglutinin, but showed a diminished response to concanavalin A. The reduced interleukin 2 receptor expression and interleukin 2 production were associated with defective concanavalin A‐induced proliferation. There was suppression of mixed lymphocyte culture reaction between the patient and two healthy donors in response to concanavalin A. In vitro immunoglobulin production experiments demonstrate that the leukaemic T cells provided an enhanced helper cell function to produce IgM, and suppressor cell function to produce IgG immunoglobulins by pokeweed mitogen‐induced normal B lymphocyte differentiation. In this study we also found that the patient's T cells proliferate in response to lipopolysaccharides, thus providing the first evidence that leukaemic (OKT4+) T cells from a prolymphocytic leukaemia patient can be stimulated by lipopolysaccharides.
Early Changes in Quiescent B Cell Physiology Subsequent to Cognate and Bystander Interaction with Helper T Cells
Authors: CAMBIER J. C. , JULIUS M. H.
Published: June 2006

We have assessed early changes in quiescent B cells Following cognate and bystander interaction with cloned helper T cells. Variables monitored include Ia expression, blastogenesis, G0 to G1 transition, and progression through cycle. We have also assessed the antigen specificity. In restriction, and dependence on membrane immunoglobulin cross‐linking of both generation and delivery of effectors that mediate B cell response. The results demonstrate that antigen presentation by quiescent B cells to T cells resulting in the generation of effectors that activate B cells is Ia‐restricted and dependent on antigen and an (mIgM and mIgD) crosslinking signal However, once generated, T cell effector functions act independently of Ia haplotype to promote Ia expression, blastogenesis, and G0 to G1, transition by most small B cells. Although these responses can be mediated in T cell supernatants, further progression of B cells through S, G2, and M is only efficient when Th cells are present in cultures. Thus, results suggest that one or more Ia unrestricted, labile and/or cell‐associated factors, not active in most conventional T cell supernatants, are necessary to stimulate proliferation of small B cells.
Impaired Mitogen‐Induced Interferon‐γ Production in Rheumatoid Arthritis and Related Diseases
Authors: STOLZENBURG T. , BINZ H. , FONTANA A. , FELDER M. , WAGENHAEUSER F.‐J.
Published: June 2006

Peripheral blood lymphocytes from patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), progressive systemic sclerosis (PSS). Reiter's disease, osteoarthritis, and from healthy volunteers were investigated for interferon‐γ (IFN‐γ) production after mitogen activation. Phytohaemagglutinin stimulation revealed an impaired IFN‐γ production in RA, SLE, and PSS but normal levels to Reiter's disease and osteoarthritis. In RA this deficiency was also seen after pokeweed mitogen. OKT3, and concanavalin A activation. No major differences were found in interleukin 2 (IL‐2) production and cell proliferation. The IL‐2 receptor expression was reduced on stimulated RA lymphocytes. The deficient IFN‐γ production was compensated in RA by co stimulation of PHA or OKT3 with phorbol myristic acetate (PMA). In addition, the combination of the calcium ionophore A 23187 and PMA induced a strong IFN‐γ secretion in all patient groups and in the controls.