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A H Kang

Publications and source records attributed to A H Kang.

At least 37 records · Page 2Linked to original sources

Herpes simplex hepatitis in pregnancy: a case report and review of the literature.

Fulminant hepatic dysfunction in the third trimester of pregnancy accompanied by fever may result from disseminated herpes simplex virus. Since 1969, 24 cases of herpes simplex hepatitis, including the current case, have been reported. Mucocutaneous lesions are present in only half of cases; therefore, suspicion for diagnosis of this disease is low. Twenty-five percent of cases were not diagnosed until autopsy. Maternal and perinatal mortality are high, approaching 39 percent for both mother and fetus. Early recognition with initiation of antiviral therapy appears to be most important in maximizing survival.

Acyclovir↗

Characterization of a peptide analog of a determinant of type II collagen that suppresses collagen-induced arthritis.

Immunization of susceptible strains of mice with type II collagen (CII) elicits an autoimmune arthritis known as collagen-induced arthritis (CIA). One analogue peptide of the immunodominant T cell determinant, A9 (CII245-270 (I260-->A, A261-->B, F263-->N)), was previously shown to induce a profound suppression of CIA when coadministered at the time of immunization with CII. In the present study, A9 peptide was administered i.p., orally, intranasally, or i.v. 2 to 4 wk following CII immunization. We found that arthritis was significantly suppressed even when A9 was administered after disease was induced. To determine the mechanism of action of A9, cytokine responses to A9 and wild-type peptide A2 by CII-sensitized spleen cells were compared. An increase in IL-4 and IL-10, but not in IFN-gamma, was found in A9 culture supernatants. Additionally, cells obtained from A9-immunized mice produced higher amounts of IL-4 and IL-10 when cultured with CII compared with cells obtained from mice immunized with A2, which produced predominantly IFN-gamma. Suppression of arthritis could be transferred to naive mice using A9-immune splenocytes. Lastly, phosphorylation of TCRzeta was not altered in the immunoprecipitates from the lysates of cells exposed to analogue peptides (A9 and A10) together with wild-type A2 in a T cell line and two I-Aq-restricted, CII-specific T hybridomas. We conclude that analogue peptide A9 is effective in suppressing established CIA by inducing T cells to produce a Th2 cytokine pattern in response to CII.

Administration, Intranasal↗

Characterization of signal transduction through the TCR-zeta chain following T cell stimulation with analogue peptides of type II collagen 260-267.

The immunodominant T cell determinant of type II collagen (CII) recognized by DBA/1 mice (I-Aq) is CII 260-267. The aims of this study were to determine the role of the amino acid residues within CII 245-270 in T cell signal transduction. To that end, we utilized I-Aq-restricted, CII-specific T cell hybridomas and examined tyrosine phosphorylation of TCR-zeta following stimulation with either wild-type CII 245-270 or a panel of analogue peptides. A variety of patterns occurred, ranging from increased phosphorylation of TCR-zeta to either partial or a complete abrogation of phosphorylation. Critical substitutions also completely abrogated the phosphorylation of ZAP70, a downstream molecule in TCR-zeta signaling. Evaluation of the supernatants of the T cell hybridomas for cytokine production in response to the peptides revealed a close correlation between the induction of phosphorylation of TCR-zeta and the amount of cytokine induced. Selected analogue peptides were tested as tolerogens in neonatal mice. Analogues that did not induce the phosphorylation of zeta chain, such as B3 (CII 251-270s263F-->N), were completely unable to induce tolerance, while analogues that caused a partial phosphorylation, such as B6 (CII 251-270s267Q-->T) and A3 (CII 245-270s269P-->A), induced partial tolerance judged by intermediate degrees of suppression of arthritis. We conclude that discrete alterations in specific amino acid residues of antigenic peptides had profound effects on T cell signaling and that the signaling correlated with T cell cytokine secretion and T cell function in the induction of tolerance and suppression of arthritis.

Amino Acid Sequence↗

Induction of autoimmune arthritis in HLA-DR4 (DRB1*0401) transgenic mice by immunization with human and bovine type II collagen.

Although associations between the expression of particular HLA genes and the susceptibility to specific autoimmune diseases has been known for some time, the role that these HLA molecules play in the autoimmune response is unclear. Through the establishment of a chimeric HLA-DR/I-E transgene, we have examined the function of the rheumatoid arthritis (RA) susceptibility allele HLA-DR4 (DRB1*0401) in presenting antigenic peptides derived from the model Ag, type II collagen (CII), and in mediating an autoimmune response. As a transgene, the chimeric DR4 molecule conferred susceptibility to an autoimmune arthritis induced by immunization with human CII or bovine CII. These mice developed an inflammatory, autoimmune arthritis that was similar both histologically and in severity to that previously described for the collagen-induced arthritis model. The DR4-mediated autoimmune arthritis was accompanied by T cell and B cell responses to both the immunogen and the autoantigen, murine CII. The DR4-restricted T cell response to human CII was focused on an immunodominant determinant within CII263-270 and a minor determinant within CII286-300, the same CII determinants recently identified for yet another RA susceptibility allele, HLA-DR1 (DRB1*0101). Thus these data demonstrate that, like HLA-DR1, HLA-DR4 is capable of binding peptides derived from human CII and therefore probably plays a role in the autoimmune response to human CII observed in RA patients.

Amino Acid Sequence↗

Evidence for preferential T cell receptor V beta gene usage and T cell clonal expansion in the synovium of BB rats with early-onset collagen-induced arthritis.

Type II collagen (CII) is a potent arthritogen in the BB rat. To determine whether a restricted group of T cells is involved in the pathogenesis of collagen-induced arthritis, lymphocytes from synovium, peripheral blood, and lymph nodes of arthritic rats were studied for T cell receptor (TCR) V beta gene usage using polymerase chain reaction (PCR). Oligoclonal TCR V beta usage was found only in synovium recovered day 2 post-arthritis onset, but not day 7; lymph node and peripheral blood T cells showed diverse TCR usage at both times. To determine whether T cell local clonal expansion occurred in synovium at day 2 of arthritis, cDNA for four TCR beta families was sequenced through VDJ regions. Strong selective expansion of TCR V beta 8.2, 4, and 17 was noted. Importantly, the dominant clonotype of V beta 8.2 was identical to that of a lymph node-derived T hybridoma specific for the immunodominant epitope in CII(181-210). Cells from synovium (day 2 postonset) analyzed by flow cytometry also showed V beta 8.2+ cell enrichment. These observations, plus finding that T cells from inflamed synovium respond to CII(181-201) in vitro, suggest the local recruitment and clonal expansion of some T cells families, possibly driven by autologous CII released during cartilage degradation.

Amino Acid Sequence↗

The cartilage collagens: a review of their structure, organization, and role in the pathogenesis of experimental arthritis in animals and in human rheumatic disease.

This contribution reviews the structure and organization of collagen molecules found in cartilage and the roles that they may play in rheumatic diseases. Cartilage is unique in its physical properties and molecular composition, and contains sufficient amounts of types II, IX, X, and XI collagen to deem these molecules as "cartilage-specific." The vitreous body of the eye, a "cartilage-like" tissue is also rich in the same collagens but is type X deficient. Types VI and XII collagen are present in cartilage as well as noncartilaginous tissues. Types II, IX, and XI collagen are organized into matrix fibrils, where type II constitutes the bulk of the fibril, type XI regulates fibril size, and type IX facilitates fibril interaction with proteoglycan macromolecules. Genetic defects in these collagens can produce mild to severe developmental abnormalities, including spondyloepiphyseal dysplasia often accompanied by an accelerated form of osteoarthritis. Sensitization with collagen can produce experimental rheumatic diseases. Type II collagen induces an erosive polyarthritis in certain strains of rats, mice, and higher primates which can resemble rheumatoid arthritis and relapsing polychondritis. Type XI collagen is arthritogenic in rats but not mice; type IX induces autoimmunity in both species but not arthritis. Arthritis is initiated by complement fixing antibodies that bind to type II collagen in autologous cartilage, and the production of these antibodies is MHC restricted and T cell dependent. It is unclear whether T cells alone can induce arthritis, although they probably help sustain it. Mapping and characterizing the of T cell epitopes on type II collagen has resulted in the synthesis of small homolog and substituted peptides of type II collagen which suppress arthritis in an antigen-specific manner by a variety of routes, including mucosal. Moreover, collagen-induced arthritis has proven a valuable model to study the contribution of cytokines and other biological agents in the pathogenesis of joint injury and how they might be used to develop new therapies. Collagen autoimmunity has been implicated in the pathogenesis rheumatoid arthritis and polychondritis. Circulating antibodies to type II collagen are found in both diseases. Antibodies to types IX and XI collagen are also present in rheumatoid sera but are less prevalent. Rheumatoid cartilage and synovium contain antibodies to type II collagen at a prevalence far greater than serum, suggesting an intra-articular antigen-driven immune process. Although effective in animal models, attempts to treat rheumatoid arthritis with orally administered type II collagen have proven elusive. Different approaches using newer formulations and selected or modified oligopeptides remain to be tested and could prove effective in the treatment of the human rheumatic diseases.

Animals↗

Immunity to type IX collagen in rodents: a study of type IX collagen for autoimmune and arthritogenic activities.

Type IX collagen (CIX), a cartilage-specific glycoprotein, constitutes < or = 10% of cartilage collagen. To ascertain whether CIX can induce arthritis as shown for type II and XI collagen (CII and CXI), outbred rats were sensitized with bovine, chick and human CIX; inbred rats, mice, and guinea pigs were sensitized with bovine CIX. Mice and guinea pigs proved resistant to arthritis, as did rats sensitized with CIX/Freund's incomplete adjuvant (FIA). Arthritis was seen in rats when 100 microg of Mycobacterium tuberculosis (Mtb) were added to FIA, but seldom with smaller doses of Mtb, suggesting the arthritis was adjuvant-induced. High levels of antibodies to rat CIX, containing complement-fixing subclasses, were detected in rat sera in addition to DTH and lymphocyte proliferation responses to rat CIX. Given the potential for CIX-induced disease, CIX-sensitized rats were injected intraperitoneally with lipopolysaccharide (LPS) to stimulate proinflammatory cytokine release, and intra-articularly with rat CIX to stimulate arthritis. LPS stimulation was ineffective; however, intra-articularly injected CIX produced transient synovitis. When rats with stable adjuvant arthritis were sensitized with CIX/FIA, significant increases in paw volume were measured compared with controls given CI/FIA. Immunohistochemical studies of actively and passively sensitized rats revealed deposits of CIX antibody, but not C3, at the joint margins where proteoglycan staining was weak. Together, these findings suggest that autoimmunity to CIX, in contrast to CII and CXI, is not directly pathogenic but may contribute to joint injury provided arthritis is initiated by an independent disease process.

Animals↗

Characterization of recombinant type II collagen: arthritogenicity and tolerogenicity in DBA/1 mice.

Recombinant human type II collagen (rhCII) was produced using both the HT1080 mammalian cell expression system (rhCIIht) and a baculovirus expression system (rhCIIbac). The biosynthesis of CII requires extensive post-translational modifications, such as the hydroxylation of prolyl and lysyl residues and glycosylation of hydroxylysyl residues. Amino acid analyses indicated that the rhCIIbac was adequately hydroxylated at prolyl residues but underhydroxylated at lysyl residues and underglycosylated compared with tissue-derived hCII, while rhCIIht was hyperhydroxylated and hyperglycosylated at lysyl residues. When the murine collagen-induced arthritis (CIA) model was used to investigate the immunological properties of the two forms of recombinant CII, each induced a high incidence of arthritis following immunization of susceptible mice when emulsified with complete Freund's adjuvant (CFA). However, the severity of the arthritis, as assessed by the number of affected limbs, was significantly higher in mice immunized with rhCIIht than in mice immunized with rhCIIbac. These data indicate that the degree of hydroxylysine glycosylation may play a role in the induction of the arthritogenic response to CII. Each of the recombinant collagens was comparable to tissue-derived hCII in their ability to induce tolerance and suppress arthritis when given as intravenous or oral tolerogens. Taken together, our data suggest that recombinant CII can be prepared in adequate amounts for therapeutic uses and that the material is immunologically comparable to tissue-derived hCII when used to induce tolerance.

Administration, Oral↗

A synthetic peptide derived from the sequence of a type I collagen receptor inhibits type I collagen-mediated platelet aggregation.

A synthetic peptide-1, an 18 amino acid residue peptide derived from a hydrophilic domain of a cloned platelet type I collagen receptor, was used to study the role of the receptor on types I and III collagen-induced platelet aggregation and the release of ATP. The peptide inhibits the type I, but not the type III, collagen-induced platelet aggregation and the release of ATP in a dose-dependent manner. The [125I]peptide-1 specifically binds to type I collagen-coated microtiter wells in a dose-dependent manner (with Kd = 10 nM). The binding of [125I]peptide-1 can be inhibited by an excess of unlabeled peptide-1 suggesting that the binding is specific. The labeled peptide-1 does not bind to type III collagen-coated microtiter wells. Results from an enzyme-linked immunosorbent assay show that the peptide reacts with the poly- and monoclonal antibodies raised against the purified platelet type I collagen receptor (Mr 65 kD). The peptide also inhibits the adhesion of platelets on type I collagen matrix and rabbit aortic segments in a dose-dependent manner. These results suggest that the reactive site of the platelet receptor for type I collagen resides in this portion of the molecule.

Amino Acid Sequence↗

Cloning, characterization, and functional studies of a nonintegrin platelet receptor for type I collagen.

A cDNA (1.6 kb) encoding a platelet protein receptor that binds type I collagen has been isolated from a human bone marrow cDNA library by using a degenerate oligonucleotide probe derived from the amino acid sequence of a CNBr fragment of the purified receptor. Computer search revealed that this cDNA represents the coding sequence of a unique protein. Using the prokaryotic expression system pKK 223-3-65 cDNA, a 54-kD recombinant protein was obtained and purified to apparent homogeneity. In an eukaryotic expression vector (pcDNA3-65 cDNA), a 65-kD protein was identified that was recognized by monoclonal anti-65 kD antibody (anti-65m). The recombinant protein binds to type I, but not to type III collagen by affinity column chromatography. The binding of the recombinant protein to type I collagen-coated Petri dishes is inhibited by anti-65m in a dose-dependent manner. The pcDNA3-65 cDNA-transfected nonadherent T cells express the protein, allowing them to attach to a type I collagen matrix, and are inhibited by anti-65m in a dose-dependent manner. Like the receptor protein purified from platelet membranes, the recombinant protein inhibits type I collagen-induced platelet aggregation and the adhesion of [14C]serotonin-labeled platelets to type I collagen in a dose-dependent manner. The recombinant protein neither binds to type III collagen-coated Petri dishes nor inhibits type III collagen and ADP-induced platelet aggregation, indicating specificity for type I collagen.

Amino Acid Sequence↗

Restricted TCR V alpha repertoire in the T cell response to a tolerogenic determinant of type II collagen.

Tolerization of B10.RIII mice (H-2r) with i.v.-injected type II collagen (CII) renders the animals resistant to induction of collagen-induced arthritis (CIA). The B10.RIII mouse is of particular interest, in that the T cell determinants that induce tolerance are different from those that induce arthritis. To characterize T cells that react with the tolerogenic determinant and play a role in regulation of arthritis, we have developed a panel of T cell hybridomas reactive with the tolerogenic T cell epitope, CII 607-621. None of the hybrids cross-reacted with either the arthritogenic CII 445-453 or murine CII. As determined by PCR and immunofluorescence, the T cell response to the tolerogenic determinant was oligoclonal, with evident preferential usage of V alpha. Through the analysis of a large panel of T cell hybridomas, preferential usage of V alpha2, J alpha44, J beta2.7, and D beta2.1 was observed. Characterization of T cells reactive with the immunodominant determinant, CII 607-621, responsible for the induction of tolerance should prove important in developing novel therapeutic approaches for the treatment of autoimmune diseases.

Amino Acid Sequence↗

An HLA-DR1 transgene confers susceptibility to collagen-induced arthritis elicited with human type II collagen.

Rheumatoid arthritis (RA) is an autoimmune disease that is strongly associated with the expression of several HLA-DR haplotypes, including DR1 (DRB1*0101). Although the antigen that initiates RA remains elusive, it has been shown that many patients have autoimmunity directed to type II collagen (CII). To test the hypothesis that HLA-DR1 is capable of mediating an immune response to CII, we have generated transgenic mice expressing chimeric (human/mouse) HLA-DR1. When the DR1 transgenic mice were immunized with human CII (hCII), they developed a severe autoimmune arthritis, evidenced by severe swelling and erythema of the limbs and marked inflammation and erosion of articular joints. The development of the autoimmune arthritis was accompanied by strong DR1-restricted T and B cell responses to hCII. The T cell response was focused on a dominant determinant contained within CII(259-273) from which an eight amino acid core was defined. The B cell response was characterized by high titers of antibody specific for hCII, and a high degree of cross-reactivity with murine type II collagen. These data demonstrate that HLA-DR1 is capable of presenting peptides derived from hCII, and suggest that this DR1 transgenic model will be useful in the development of DR1-specific therapies for RA.

Adjuvants, Immunologic↗

Collagen-induced arthritis, an animal model of autoimmunity.

Collagen induced arthritis (CIA) is an autoimmune model that in many ways resembles rheumatoid arthritis (RA). Immunization of genetically susceptible strains of rodents and primates with type II collagen (CII) leads to the development of a severe polyarticular arthritis that is mediated by an autoimmune response. Like RA, synovitis and erosions of cartilage and bone are hallmarks of CIA, and susceptibility to both RA and CIA is linked to the expression of specific MHC class II molecules. Although not identical to RA, CIA clearly establishes the biological plausibility that an autoimmune reaction to a cartilage component can lead to a chronic, destructive, polyarthritis. Although it is induced in susceptible animals by immunization with heterologous CII, it is the autoreactive component of the immune response that leads to disease. A wealth of evidence indicates that synovitis is initiated by the production of pathogenic autoreactive antibodies capable of fixing and activating complement. The elucidation of the specific amino acid sequences of collagen that are recognized by the MHC molecules has enabled at least two approaches to specific immunotherapy to be considered. Firstly, small synthetic peptides representing dominant epitopes have been used as effectively as the original antigen as a tolerogen. The rather fastidious physicochemical properties of collagen that make it difficult for its routine use in therapy are thereby circumvented by the use of oligopeptides. Secondly, analysis of the specific amino acid side chains that are involved in MHC contact and TCR recognition enables analog peptides to be devised which can specifically and exquisitely inhibit the response to CII, preventing the onset of arthritis. Further investigations involving this model may contribute to the development of specific immunotherapies in the human disorder.

Amino Acid Sequence↗

Suppression of murine collagen-induced arthritis by nasal administration of collagen.

DBA/1 mice were administered type II collagen (CII) or collagen peptides intranasally before systemic immunization to determine whether tolerance could be induced and autoimmune arthritis suppressed. Although prior experiments have demonstrated that collagen given intravenously or orally is effective, the respiratory mucosal route offers several theoretical advantages for dosing peptides, in addition to ease of use. Intact CII, CB11 and a synthetic peptide containing the immunodominant T-cell epitope recognized by H-2q mice were all effective in reducing the incidence and severity of arthritis and the immune response to CII. Since previous studies have demonstrated the importance of IgG2 antibody subclasses to the induction of collagen-induced arthritis, total immunoglobulin G (IgG), IgG1, and IgG2a and IgG2b were measured. IgG2 antibody subclasses were significantly downregulated by the treatment regimen, whereas a slight decrease in IgG1 antibodies was noted that was not significant. In an effort to determine the mechanism by which arthritis was attenuated, cervical lymph node and spleen cells from treated mice were cultured separately with CII and supernatants tested for the presence of T-cell lymphokines. The cells provided a T-helper 2 (Th2)-like response to CII, with T cells from lymph nodes secreting interleukin-4 (IL-4) and splenocytes secreting both IL-4 and IL-10, whereas a Th1-like response was detected in immunized mice not tolerized with CII. These findings indicate that the downregulation of arthritis that occurs with intranasal administration of CII is associated with Th2-type lymphokine profile and a decrease in complement-fixing antibody subclass.

Administration, Intranasal↗

Involvement of phosphoprotein phosphatase 1 in collagen-platelet interaction.

The binding of type I collagen to its receptor initiates platelet aggregation, but the relationship of the receptor to other signal transduction components is not yet established. Correlation of platelet aggregation and anti-type I collagen receptor antibody immunoprecipitation of type I collagen treated [32PO4]-labeled platelets showed that there are two phosphoproteins (M(r) 53 kDa and 21 kDa) that coprecipitated with the 65 kDa platelet type I collagen receptor. In the present investigation, we have identified one of the phosphoproteins. A soluble component the 100,000x g supernatant fraction of 53 kDa protein is recognized by polyclonal anti-PP1 antibody. The activity of the precipitated phosphatase is inhibited by okadaic acid and inhibitor 1, suggesting that it is protein phosphatase 1 (PP 1). Phosphorylation decreases PP 1 activity as was found with [32PO4]-phosphorylase b as the substrate. The immunocoprecipitation of the type-1 collagen receptor and PP 1 inot the result of cross reactivity of the anti-type I collagen receptor antibody with the PP I protein. These results indicate that the platelet type I collagen receptor, PP 1, and unidentified 21 kDa protein are in close association with the platelet type I collagen receptor upon the binding of type I collagen by the receptor.

Blood Platelets↗

Autoantibodies to murine type II collagen in collagen-induced arthritis: a comparison of susceptible and nonsusceptible strains.

Collagen-induced arthritis (CIA) is an experimental autoimmune disease elicited in genetically susceptible strains of mice by immunization with heterologous type II collagen. This experimental disease is mediated by the immune response of both T cells and B cells, and susceptibility is restricted by the class II molecules of the MHC. In this study we identify specific epitopes bound by autoantibodies elicited through immunization of several haplotypes of C57BL/10 mice with chick alpha1 (II)-CB11. ELISA analysis using a panel of 15-mer murine type II collagen peptides revealed a pattern of autoantibody epitope specificity that was remarkably similar among CIA-susceptible and nonsusceptible congenic strains, regardless of class II haplotype. However, one epitope was identified that was bound only by autoantibodies from CIA-susceptible strains bearing I-A(q) (B10.Q and B10.QbetaBR). In addition, this epitope was also present within affinity-purified Ab obtained from the CIA-susceptible strain DBA/1 (I-A(q)). Analyses of immune serum from B10.Q and B10.QbetaBR mice revealed that a subset of the antibodies binding this epitope were of the IgG2 subclass, and therefore efficient at fixing complement, a requirement for pathogenicity of the Abs in CIA.

Amino Acid Sequence↗

Identification and characterization of a tolerogenic T cell determinant within residues 181-209 of chick type II collagen.

The murine model of collagen-induced arthritis is characterized by the development of an immune response against joint cartilage. Arthritis can be significantly suppressed by the administration of type II collagen (CII) or one of the CNBr peptides, CB11 (CII 124-402) as a tolerogen prior to immunization. We have previously shown that two synthetic peptides, representing sequences CII 260-270 and CII 181-209, are effective tolerogens. In this paper, we now characterize the T cell determinant with CII 181-209. A series of synthetic peptides overlapping CII 181-209 and analogs of chick CII 181-209 containing site-directed amino acid substitutions was developed and cultured with T cells from DBA/1 mice immunized with CII. Supernatants were collected and analyzed for the presence of the T cell lymphokine IFN-gamma. These data indicate the critical T cell determinant to be located within CII 190-200. This conclusion is further supported by the observation that an unodecapeptide representing CII 190-200 was just as effective as CII 181-209 in suppressing arthritis and anti-CII antibody response when tested as a tolerogen. Analogs containing single amino acid substitutions at residues 191, 194, 197, 198, or 200 were significantly less effective in inducing T cell responses. Each of these peptide analogs was then given as neonatal tolerogens to DBA/1 mice. Mice were subsequently immunized and observed for the development of arthritis. These studies identified residues 194, 197, 198, and 200, and probably residue 191, as critical for tolerance and the suppression of arthritis. Elucidation of the fine structures of T cell determinants which are critical for suppression of arthritis should allow these techniques to be used for developing specific immunotherapeutic approaches to autoimmune arthritis.

Amino Acid Sequence↗

Type XI and II collagen-induced arthritis in rats: characterization of inbred strains of rats for arthritis-susceptibility and immune-responsiveness to type XI and II collagen.

To determine the relationship between susceptibility to bovine type XI and II (BXI and BII) collagen-induced arthritis, we immunized 14 inbred and one outbred strains of rats with BXI and BII. Susceptibility to BXI-arthritis corresponded largely with susceptibility, or resistance, to BII-arthritis. LEW, BB, WF, DA, and WKY were readily susceptible to BXI- and BII-arthritis. Likewise, BII-resistant F344 and BN rats were BXI-resistant. Some strains responded differently to BXI and BII. BUF and COP, which are moderately susceptible to BII, were BXI-resistant, whereas the BII-resistant rats, DA.1N and WF.1N, were partially susceptible to BXI. (F344 x BN) F1 hybrids responded to both collagens suggesting gene complementation. Arthritis occurred in all strains producing the highest titer antisera (LEW, WF and BB). Antibody responses to BXI and BII were generally commensurate within individual strains. DA were susceptible to arthritis but produced low levels of antibody comparable to BN rats which were arthritis-resistant. BXI and BII-susceptibility was variable in rats producing intermediate antibody responses. Antibodies to RXI were detected in all BXI-immunized rats, whereas antibodies to RV and RII were uniformly weaker. DTH to RXI and RII was strong in both groups of rats, correlating poorly with arthritis and antibody responses. These studies show that phenotypic susceptibility to BXI- and BII-arthritis are largely concordant among inbred rat strains but clear differences exist in certain strains; multiple genes are likely involved.

Animals↗