Possible role of V beta T cell receptor genes in susceptibility to collagen-induced arthritis in mice

Zerumbone Protects Rats from Collagen-Induced Arthritis by Inhibiting Oxidative Outbursts and Inflammatory Cytokine Levels

Rheumatoid arthritis (RA) is an immunocompromised disorder characterized by a marked increase in the synthesis of inflammatory molecules that stimulates the destruction of bones and cartilage. The conventional treatment modalities for RA are associated with adverse side effects and lack sensitivity, suggesting an immediate demand for alternate beneficial therapeutic remedies. The current study sought to understand more about zerumbone's anti-inflammatory properties in diagnosing collagen-induced arthritis (CIA) in experimental animals. The current study observed that zerumbone reduced clinical severity in CIA-induced animals compared to healthy animals. Zerumbone administration significantly decreased (p < 0.001) the concentration of SOD, CAT, GR, and GSH in treatment groups. Zerumbone administration drove down significantly (p < 0.001) the concentration of inflammatory cytokine molecules. Zerumbone was effective in bringing significant changes in levels of MPO, NO, LDH, MMP-8, and ELA. The therapeutic potential of zerumbone was found to be associated with reduced joint destruction and restored normal histology in the cartilage and tissue. Adsorption, distribution, metabolism, excretion, and toxicity studies were used to determine the druglike properties of zerumbone. ProTox-II studies revealed that zerumbone did not possess toxic properties like hepatotoxicity, immunotoxicity, carcinogenicity, mutagenicity, and cytotoxicity. Therefore, the present study evaluated the therapeutic properties of zerumbone in CIA animal models.

Zingerone (4-(four-hydroxy-3-methylphenyl) butane-two-1) modulates adjuvant-induced rheumatoid arthritis by regulating inflammatory cytokines and antioxidants

OBJECTIVE

Ginger (Zingiber officinale Roscoe) is considered to be one of the most commonly consumed dietary condiments of the world. The present study was designed to explicate the protective role of zingerone; an active ingredient of ginger in complete Freund's adjuvant (FCA)-immunized arthritic rats.

METHODS

24 Wistar rats were divided into 4 groups with 6 rats each. Group I as control followed by group II, III and IV were treated with single intradermal injection of FCA (0.1 ml = 100 µg) to induce rheumatoid arthritis. Group III and IV were also administered with zingerone orally at 25 mg/kg b.w for 3 weeks at two different time points.

RESULTS

Adjuvant-treated rats exhibited a significant increase in lipid peroxidation and a reduction in the enzymatic antioxidants such as SOD, catalase and GPx, in the liver and joint tissues. Moreover, FCA inoculation resulted in the increase in levels of NF-κB, TGF-β, TNF-α, IL-1β, IL-6 and Hs-CRP and a decrease in IL-10 levels. Zingerone significantly reduced the levels of NF-κB, TGF-β, TNF-α, IL-1β, IL-6 and Hs-CRP and markedly increased IL-10 levels. Levels of antioxidant enzymes were also restored by zingerone treatment.

DISCUSSION

Oral administration of zingerone ameliorated inflammatory outburst and decreased oxidative stress, suggesting its role in the prevention of rheumatoid arthritis. Further mechanistic insights are necessary to study the exact mechanism involved.

Role of HLA class II genes in susceptibility/resistance to inflammatory arthritis: studies with humanized mice

Predisposition to develop rheumatoid arthritis (RA) has been associated with certain human leukocyte antigen (HLA) class II molecules, although the mechanism is still unknown. Various experimental animal models of inflammatory arthritis have been studied to address the role of major histocompatibility complex (MHC) genes in pathogenesis. We have generated transgenic mice expressing HLA class II molecules (DR and DQ) lacking complete endogenous class II molecules to study the interactions involved between class II molecules (DQ and DR) and to define the immunologic mechanisms in inflammatory arthritis. The HLA transgene can positively select CD4(+) T cells expressing various V beta T-cell receptors, and a peripheral tolerance is maintained to transgenic HLA molecules. The expression of HLA molecules on various cells in these mice is similar to that known in humans. In this review, we describe collagen-induced arthritis as a model for human inflammatory arthritis using these transgenic mice. The transgenic mice carrying RA-susceptible haplotype develop gender-biased inflammatory arthritis with clinical and histopathological similarities to RA. Our studies show that polymorphism of HLA class II genes determine the predisposition to rheumatoid/inflammatory arthritis and the epistatic interactions between HLA-DQ and HLA-DR molecules dictate the severity, progression, and modulation of the disease.

Plasma 3-nitrotyrosine is a biomarker in animal models of arthritis: Pharmacological dissection of iNOS' role in disease

The contribution of inducible nitric oxide synthase (iNOS) to oxidative/nitrative stress is well-documented in inflammation, but difficult to quantify. Using a novel, recently developed assay for 3-nitrotyrosine (3-NT), we characterized iNOS activity and its inhibition in preclinical models of inflammation. In particular, we utilized the 3-NT assay to assess the role of iNOS in the disease pathology as well as for proof of pharmacology of iNOS inhibitors in an acute endotoxin challenge model, in models of rheumatoid arthritis (RA) such as rat adjuvant- and collagen-induced arthritis (AIA and CIA) and a model of osteoarthritis (OA) such as rat sodium monoiodoacetate-induced arthritis (MIA). Quantification of nitrotyrosine was performed using immuno-affinity 2-D LC-MS/MS assay. This assay is a very specific and reproducible and is amenable to a number of biological fluids. Plasma levels of 3-NT were significantly elevated in an acute model of inflammation (rat LPS) and in models of rheumatoid arthritis (adjuvant- and collagen-induced arthritis), and osteoarthritis (monoiodoacetate-induced arthritis). Plasma 3-NT correlated with the severity of the inflammatory response; thus, a 20-fold increase was observed in the rat LPS model, a 10-fold increase in AIA, and only a 2.5-fold elevation in CIA. Pharmacological intervention with iNOS inhibitors decreased 3-NT levels and associated pathology. 3-NT determination allowed for better elucidation of the role of iNOS in RA and OA disease pathology and provided proof of pharmacology for NOS inhibitors in animal models of RA and OA.

Exacerbation of autoimmune arthritis by copolymer-I through promoting type 1 immune response and autoantibody production

Copolymer-I (COP-I) is an unique immune regulatory polymer that has been shown to suppress experimental autoimmune encephalomyelitis (EAE) and is a treatment option for multiple sclerosis (MS). To investigate whether its immune suppressive effects can be extended to other autoimmune diseases, we treated mice with COP-I during the induction of collagen-induced arthritis (CIA). Our results show that COP-I treatment exacerbated CIA, leading to faster onset, more severe and longer-lasting disease. The mechanisms underlying the exacerbation of CIA by COP-I treatment include enhanced activation and inflammatory cytokine production by autoreactive T cells and elevated production of autoreactive antibodies. In addition, germinal center response was significantly enhanced by COP-I treatment. Thus, great caution should be taken when COP-I is to be used in MS patients with other autoimmune complications or its potential therapeutic effects are to be extended beyond autoimmune demyelinating diseases.

Prevention of collagen-induced arthritis in mice by Cervus korean TEMMINCK var. mantchuricus Swinhoe

The effect of water extract of deer antler (DAA) prepared from the pilose antler of Cervus korean TEMMINCK var. mantchuricus Swinhoe (Nokyong) on collagen-induced mouse rheumatoid arthritis (RA) model was studied. Identification of common DAA capable of affording protection or modulating the onset and severity of arthritis may have important human health implications. DAA has been shown to possess anti-inflammatory and anti-carcinogenic properties in experimental animals. In this study, we determined the effect of DAA-injection on collagen-induced arthritis in mice. In three independent experiments, mice given DAA in water exhibited significantly reduced incidence of arthritis (30-45%) as compared with mice not given DAA in water (86-98%). The arthritis index also was significantly lower in DAA-injected animals. Western blot analysis showed a marked reduction in the expression of inflammatory mediators such as cyclooxygenase 2, IFN-γ, and tumor necrosis factor α in arthritic joints of DAA-injected mice. The neutral endopeptidase activity was approximately six-fold higher in arthritic joints of non-DAA-injected mice in comparison to non-arthritic joints of unimmunized mice, whereas it was only two-fold higher in the arthritic joints of DAA-injected mice. Additionally, total IgG and type II collagen-specific IgG levels were lower in serum and arthritic joints of DAA-injected mice. Taken together our studies suggest that DAA may be useful in the prevention of onset and severity of arthritis.

Antigen-specific expansion of TCR Vbeta3+ CD4+ T cells in the early stage of collagen-induced arthritis and its arthritogenic role in DBA/1J mice

To investigate type II collagen (CII)-specific CD4+ T cell receptors involving in Collagen-induced arthritis (CIA) in DBA/1J mice as a model of rheumatoid arthritis in humans, TCR Vbeta usage in draining lymph nodes (dLNs) was assessed by flow cytometric analysis at 3, 5, and 8 weeks after bovine CII immunizations. In the early stage of CIA, the draining lymph node CD4+ T cells from CIA mice showed a higher proportion of CD4+ Vbeta3+ subsets compared with those from control mice. The CD4+ Vbeta3+ T cells were specifically and primarily expanded by antigen-specific stimulation in in vitro culture of dLNs lymphocytes and splenocytes from CIA mice. In addition, CII-reactive response was observed when CD4+ Vbeta3+ T cells were added to a non-responding T cell population. The adoptive transfer of CD4+ Vbeta3+ T cells produced exaggerated arthritis compared with that in the control group. Our results indicate that CD4+ Vbeta3+ T cells, which were selectively expanded in dLN of CIA mice, play a pivotal role in CIA pathogenesis.

IgG Fc receptor polymorphisms and association with autoimmune disease

The aim of this study was to investigate whether a genetic polymorphism of Fc gammaRIII exists in mice, which could explain the different susceptibility to pathogenic IgG anti-collagen type II (CII) antibodies in mice carrying the collagen-induced arthritis (CIA)-susceptible H-2q haplotype. The gene for Fc gammaRIII was sequenced in 11 common mouse strains, and the results revealed three different haplotypes of mouse Fc gammaRIII: Fc gammaRIII:V, Fc gammaRIII:H and Fc gammaRIII:T. To study the consequences of this polymorphism, we generated mice carrying the Fc gammaRIII:H haplotype from the CIA-susceptible, H-2q-positive DBA/1 mouse or the Fc gammaRIII:V haplotype from the CIA-resistant, H-2q-positive SWR mouse. After CII immunization or transfer of IgG anti-CII antibodies, Fc gammaRIII:H-expressing mice, but not Fc gammaRIII:V-expressing mice, developed progressively severe arthritis. We also investigated if C5, in addition to Fc gammaRIII polymorphism, could affect the susceptibility to the pathogenic IgG anti-CII antibodies in H-2q-positive mice. Here we show that SWR mice, naturally deficient in C5, can develop CIA when supplemented with C5 and that anti-C5 antibody treatment of Fc gammaRIII:H-expressing mice inhibits arthritis development. These data demonstrate for the first time a genetic polymorphism of Fc gammaRIII in mice that may, together with C5, regulate induction of autoimmune disease.

Crystal structures of T cell receptor (beta) chains related to rheumatoid arthritis

The crystal structures of the Vbeta17+ beta chains of two human T cell receptors (TCRs), originally derived from the synovial fluid (SF4) and tissue (C5-1) of a patient with rheumatoid arthritis (RA), have been determined in native (SF4) and mutant (C5-1(F104-->Y/C187-->S)) forms, respectively. These TCR beta chains form homo-dimers in solution and in crystals. Structural comparison reveals that the main-chain conformations in the CDR regions of the C5-1 and SF4 Vbeta17 closely resemble those of a Vbeta17 JM22 in a bound form; however, the CDR3 region shows different conformations among these three Vbeta17 structures. At the side-chain level, conformational differences were observed at the CDR2 regions between our two ligand-free forms and the bound JM22 form. Other significant differences were observed at the Vbeta regions 8-12, 40-44, and 82-88 between C5-1/SF4 and JM22 Vbeta17, implying that there is considerable variability in the structures of very similar beta chains. Structural alignments also reveal a considerable variation in the Vbeta-Cbeta associations, and this may affect ligand recognition. The crystal structures also provide insights into the structure basis of T cell recognition of Mycoplasma arthritidis mitogen (MAM), a superantigen that may be implicated in the development of human RA. Structural comparisons of the Vbeta domains of known TCR structures indicate that there are significant similarities among Vbeta regions that are MAM-reactive, whereas there appear to be significant structural differences among those Vbeta regions that lack MAM-reactivity. It further reveals that CDR2 and framework region (FR) 3 are likely to account for the binding of TCR to MAM.

T cell receptors recognizing type II collagen in HLA-DR-transgenic mice characterized by highly restricted V beta usage

OBJECTIVE

To determine the T cell receptor (TCR) structure recognizing type II collagen (CII) in HLA-DR-transgenic mice, and to examine the role of T cells with certain V(beta)-chains in collagen-induced arthritis (CIA).

METHODS

T cell hybridomas were established from DR1- and DR4-transgenic mice and selected for their responses to CII and CII peptide containing the T cell determinants. RNA was extracted and reverse transcribed into complementary DNA, which was then amplified using appropriate V(beta)- and V(alpha)-subfamily-specific primers. The polymerase chain reaction products were purified and directly sequenced. To determine the role of T cells with certain V(beta)-chains in CIA, V(beta)-subfamily-specific antibodies were administered and the development and characteristics of arthritis were determined.

RESULTS

TCRs of 23 clonally distinct T cell hybridomas that were derived from DR1-transgenic mice and that were reactive to the CII peptide containing the immunodominant determinant were analyzed. These hybridomas predominantly used the TCR V(beta)14 and V(beta)8 gene segments (70% and 30%, respectively). The same restriction in V(beta) usage was also found in CII-reactive T cell hybridomas from DR4-transgenic mice. There was also restricted use of V(alpha) genes, although this was less marked than that of V(beta). In contrast, the hybridomas expressed a diverse third complementarity-determining region. Deletion of both V(beta)14-bearing and V(beta)8-bearing T cells significantly reduced the incidence and severity of CIA.

CONCLUSION

These data demonstrate that DR1 and DR4 not only bind and present the same CII immunodominant peptide, but also stimulate a highly restricted subset of T cells.

IFNgamma deficient C57BL/6 (H-2b) mice develop collagen induced arthritis with predominant usage of T cell receptor Vbeta6 and Vbeta8 in arthritic joints

BACKGROUND

Transgenic deficiency in interferon gamma (IFNgamma) or IFNgamma receptor makes resistant strains of mice bearing H-2(b) or H-2(d) susceptible to collagen induced arthritis (CIA).

OBJECTIVE

To determine whether the escape from regulation of disease susceptibility at the major histocompatibility complex level involves a new use of autoimmune T cells expressing T cell receptor (TCR) Vbeta that vary from the cell populations previously identified within arthritic joints.

METHODS

Arthritis was induced by a standard protocol with type II bovine collagen (CII) in complete Freund's adjuvant. Clinical features, histopathology, immunological responses, and TCR profile in arthritic joints in IFNgamma knockout C57BL/6 (B6.IFNgamma KO) mice (H-2(b)) were compared directly with those in DBA/1 mice (H-2(q)).

RESULTS

60-80% of B6.IFNgamma KO mice developed a progressive arthritis with a similar clinical course to classical CIA in DBA/1 mice. The affected joints in B6.IFNgamma KO mice had an erosive form of arthritis with similar features to joint disease in DBA/1 mice. B6.IFNgamma KO mice produced significantly higher levels of IgG2b and IgG1 autoantibodies to murine CII and showed increased proliferative response to CII compared with B6 mice. Comparable levels of interleukin 1beta and tumour necrosis factor alpha expression were detected in arthritic joints from beta6.IFNgamma KO and DBA/1 mice. B6.IFNgammaKO mice used predominantly TCR Vbeta6 and Vbeta8 in arthritic joints. This TCR Vbeta profile is similar to that found in DBA/1 mice with CIA.

CONCLUSIONS

C57BL/6 mice deficient in IFNgamma production can develop arthritis that resembles classical CIA. These data suggest that IFNgamma is a key factor mediating susceptibility to CIA.

Genetic Control of Tolerance to Type II Collagen and Development of Arthritis in an Autologous Collagen-Induced Arthritis Model

T cell recognition of the type II collagen (CII) 260-270 peptide is a bottleneck for the development of collagen-induced arthritis (CIA), an animal model of rheumatoid arthritis. We have earlier made C3H.Q mice expressing CII with glutamic acid instead of aspartic acid at position 266 (the MMC-C3H.Q mouse), similar to the rat and human CII epitope, which increases binding to MHC class II and leads to effective presentation of the peptide in vivo. These mice show T cell tolerance to CII, but also develop severe arthritis. The present investigation shows that non-MHC genes play a decisive role in determining tolerance and arthritis susceptibility. We bred MMC into B10.Q mice, which display similar susceptibility to CIA induced with rat CII as the C3H.Q mice. In contrast to MMC-C3H.Q mice, MMC-B10.Q mice were completely resistant to arthritis. Nontransgenic (B10.Q x C3H.Q)F(1) mice were more susceptible to CIA than either of the parental strains, but introduction of the MMC transgene leads to CIA resistance, showing that the protection is dominantly inherited from B10.Q. In an attempt to break the B10-mediated CIA protection in MMC-transgenic mice, we introduced a transgenic, CII-specific, TCR beta-chain specific for the CII(260-270) glycopeptide, in the highly CIA-susceptible (B10.Q x DBA/1)F(1) mice. The magnification of the autoreactive CII-specific T cell repertoire led to increased CIA susceptibility, but the disease was less severe than in mice lacking the MMC transgene. This finding is important for understanding CIA and perhaps also rheumatoid arthritis, as in both diseases MHC class II-restricted T cell recognition of the glycosylated CII peptide occurs.

Potential biologic agents for treating rheumatoid arthritis

The encouraging clinical results observed in trials using anti-TNF therapy clearly warrant further studies to determine whether TNF inhibitors are capable of modifying the destructive component of this disease in long-term follow-up studies as well as to assess the safety of long-term use (see the article by Keystone in this issue). It is also reasonable to propose that interfering with the cytokine cascade earlier in the course of disease may be of even greater therapeutic benefit. As the pathogenetic mechanisms in RA are more clearly defined, especially in early disease and in those individuals destined to develop severe disease, the potential of other biologic agents to specifically inhibit these critical pathways may provide better treatments for our patients. Many potential targets in the immune-mediated process of RA are currently being rigorously evaluated in clinical trials. Use of combinations of biologic therapies, perhaps in human patients with RA, should be of considerable interest in future trials.

A role for complement in antibody-mediated inflammation: C5-deficient DBA/1 mice are resistant to collagen-induced arthritis

Collagen-induced arthritis (CIA) represents an animal model of autoimmune polyarthritis with significant similarities to human rheumatoid arthritis that can be induced upon immunization with native type II collagen. As in rheumatoid arthritis, both cellular and humoral immune mechanisms contribute to disease pathogenesis. Genotypic studies have identified at least six genetic loci contributing to arthritis susceptibility, including the class II MHC. We have examined the mechanism of Ab-mediated inflammation in CIA joints, specifically the role of complement activation, by deriving a line of mice from the highly CIA-susceptible DBA/1LacJ strain that are congenic for deficiency of the C5 complement component. We show that such C5-deficient DBA/1LacJ animals mount normal cellular and humoral immune responses to native type II collagen, with the activation of collagen-specific TNF-alpha-producing T cells in the periphery and substantial intra-articular deposition of complement-fixing IgG Abs. Nevertheless, these C5-deficient mice are highly resistant to the induction of CIA. These data provide evidence for an important role of complement in Ab-triggered inflammation and in the pathogenesis of autoimmune arthritis.

Intravenous tolerization with type II collagen induces interleukin-4-and interleukin-10-producing CD4+ T cells

Intravenous (i.v.) administration of type II collagen (CII) is an effective way to induce tolerance and suppress disease in the collagen-induced arthritis (CIA) model. In this study, we demonstrated that a single i.v. dose of CII (as low as 0.1 mg/mouse) completely prevented the development of CIA. This suppression was accompanied by decreases in levels of antibody specific for the immunogen, bovine CII and autoantigen, mouse CII. Splenocytes obtained from CII-tolerized mice and stimulated with CII in vitro produced predominantly the T helper 2 (Th2)-type cytokines interleukin-4 (IL-4) and interleukin-10 (IL-10). In contrast, cells obtained from mice immunized with CII produced predominantly interferon-gamma (IFN-gamma). Two-colour flow cytometric analysis of cytokine expression and T-cell phenotype demonstrated that CD4+ cells and not CD8+ or gammadelta+ cells were the predominant regulatory cells producing IL-4 and IL-10. Transgenic mice bearing a T-cell receptor (TCR) specific for CII had a greater increase in the number of IL-4-secreting CD4+ cells, as well as a marked increase of IL-4 in culture supernatants. This cytokine was produced by transgene-bearing T cells. Elucidation of mechanisms for the induction of tolerance in mature T cells is an important line of study in autoimmune models because of the potential application for treating organ-specific autoimmune disease.

Prevention of collagen-induced arthritis in mice by a polyphenolic fraction from green tea

Identification of common dietary substances capable of affording protection or modulating the onset and severity of arthritis may have important human health implications. An antioxidant-rich polyphenolic fraction isolated from green tea (green tea polyphenols, GTPs) has been shown to possess anti-inflammatory and anticarcinogenic properties in experimental animals. In this study we determined the effect of oral consumption of GTP on collagen-induced arthritis in mice. In three independent experiments mice given GTP in water exhibited significantly reduced incidence of arthritis (33% to 50%) as compared with mice not given GTP in water (84% to 100%). The arthritis index also was significantly lower in GTP-fed animals. Western blot analysis showed a marked reduction in the expression of inflammatory mediators such as cyclooxygenase 2, IFN-gamma, and tumor necrosis factor alpha in arthritic joints of GTP-fed mice. Histologic and immunohistochemical analysis of the arthritic joints in GTP-fed mice demonstrated only marginal joint infiltration by IFN-gamma and tumor necrosis factor alpha-producing cells as opposed to massive cellular infiltration and fully developed pannus in arthritic joints of non-GTP-fed mice. The neutral endopeptidase activity was approximately 7-fold higher in arthritic joints of non-GTP-fed mice in comparison to nonarthritic joints of unimmunized mice whereas it was only 2-fold higher in the arthritic joints of GTP-fed mice. Additionally, total IgG and type II collagen-specific IgG levels were lower in serum and arthritic joints of GTP-fed mice. Taken together our studies suggest that a polyphenolic fraction from green tea that is rich in antioxidants may be useful in the prevention of onset and severity of arthritis.

Epitope glycosylation plays a critical role for T cell recognition of type II collagen in collagen-induced arthritis

Immunization of mice with type II collagen (CII) leads to collagen-induced arthritis (CIA), a model for rheumatoid arthritis. T cell recognition of CII is believed to be a critical step in CIA development. We have analyzed the T cell determinants on CII and the TCR used for their recognition, using twenty-nine T cell hybridomas derived from C3H.Q and DBA/1 mice immunized with rat CII. All hybridomas were specific for the CII(256-270) segment. However, posttranslational modifications (hydroxylation and variable O-linked glycosylation) of the lysine at position 264 generated five T cell determinants that were specifically recognized by different T cell hybridoma subsets. TCR sequencing indicated that each of the five T cell epitopes selected its own TCR repertoire. The physiological relevance of this observation was shown by in vivo antibody-driven depletion of TCR Valpha2-positive T cells, which resulted in an inhibition of the T cell proliferative response in vitro towards the non-modified CII(256-270), but not towards the glycosylated epitope. Most hybridomas (20/29) specifically recognized CII(256-270) glycosylated with a monosaccharide (beta-D-galactopyranose). We conclude that this glycopeptide is immunodominant in CIA and that posttranslational modifications of CII create new T cell determinants that generate a diverse TCR repertoire.

Inhibition of type II collagen-induced arthritis in rats by triptolide

The effects of purified triptolide, a diterpenoid triepoxide compound derived from the Chinese traditional anti-rheumatic medicinal plant extract, Tripterygium wilfordii Hook f (TWHf), were determined in type II collagen-induced arthritis (CIA) in rats. Lewis rats were immunized with bovine type II collagen and treated with purified triptolide 0.1 mg/kg/day or control (vehicle for triptolide) by daily gavage feedings for 28 days. Triptolide was well-tolerated with no evidence of toxicity. Treatment with triptolide resulted in significant delay in time to onset of arthritis (P = 0.039), as well as significantly decreased arthritis incidence (P = 0.024), clinical arthritis severity score (P < 0.0001), histopathological arthritis severity score (P < 0.0001), and in vivo cell-mediated immunity to collagen (P = 0.0004). Triptolide appeared to be a potent immunomodulatory inhibitor of CIA in rats and this may account for the previously observed anti-rheumatic properties of crude extracts of TWHf, although more extensive studies will be needed to confirm these effects.

T cells infiltrating the skin of Tsk2 scleroderma-like mice exhibit T cell receptor bias

The T cell repertoire expressed by Tsk2 mice, a novel experimental model of systemic sclerosis, was examined to determine whether cells infiltrating the areas of involved skin exhibit a T cell receptor (TCR) bias. Reverse transcription-polymerase chain reactions (RT-PCR) were conducted using RNA extracted from lymph nodes and skin from TSk2 mice and from normal mice, with an oligonucleotide primer library specific for the variable region of the TCR (beta) chain. RT-PCR signals were observed in all lymph node cell (LNC) samples from both Tsk2 mice and control mice, with eighteen of the twenty-one Vbeta types present. In contrast, cDNA extracted from areas of involved skin from Tsk2 mice exhibited a restricted pattern, with positive Vbeta signals corresponding to eight T cell subtypes (Vbeta1, 6, 8.1, 8.2, 10, 11, 16, and 18). Band strength analysis revealed that three Vbeta subtypes dominated within this restricted pattern (Vbeta8.1, 11, and 18). Moreover, this pattern of Vbeta bias was consistent among the four skin samples from different Tsk2 mice. These data suggest that a restricted T cell population participates in the inflammatory cell infiltrate of Tsk2 skin.

Anti-T-cell receptor therapy in murine experimental systemic lupus erythematosus

Experimental systemic lupus erythematosus (SLE), similar to that observed after immunization with the human anti-DNA mAb 16/6 Id+, could be induced in mice by injection of 16/6 Id specific T-cell lines. The above T-cell lines were exclusively CD4+ CD8- and the majority of cells expressed the Vbeta8 T-cell receptor (TCR) gene products. Furthermore, lymph node cells of mice immunized with the 16/6 Id were enriched with CD4+ Vbeta8+ T-cells. The TCR used by 16/6 Id-specific T-cells showed a limited homology in their CDR3 junctional regions. Nevertheless, mice injected with the anti-Vbeta8 mAb developed autoantibody titers that were not significantly different from those found in the non-treated, 16/6 Id-injected group.

Genetic control of susceptibility to collagen-induced arthritis in T cell receptor beta-chain transgenic mice

OBJECTIVE

To study the genes in the mouse background which predispose to the development of collagen-induced arthritis (CIA).

METHODS

T cell receptor beta transgenic (TCRbetaL) mice that have a T cell repertoire that predisposes to the development of CIA were used. Classic genetic studies and microsatellite gene mapping were done in (SWR-betaL x DBA/1)F2 hybrid mice.

RESULTS

Besides TCRbeta, major histocompatibility complex class II, and Igh-C, at least 2 other genes are absolutely required for CIA development in these mice. A strict association of CIA with the presence of functional complement C5 allele (Hc1) was found, suggesting that Hc1 or a closely linked gene might be one of these essential genes.

CONCLUSION

This study provides new evidence of the pathogenetic role of complement C5 in CIA. Furthermore, these transgenic mice may facilitate molecular identification of other genes that predispose to CIA.

TCRV and TCRJ gene usage in MBP responding T cells from (B10.PL x PL/J)F1 mice is biased towards that of B10.PL mice

We analyzed myelin basic protein (MBP) specific T cell hybridoma clones from (B10.PL x PL/J)F1 mice. MBP-reacting T cell hybridomas from F1 mice preferentially expressed B10.PL TcraV2.3 (53%) and B10.PL TcraV4.2 (13%) with minor expression of TcraV4.4 (13%) gene segments. A dominant expression of TcrbV8.2 (73%) accompanying with TcrbV8.1 (20%) and TcrbV13 (7%) gene segments have been identified in these MBP-reacting T cell hybridomas from F1 mice. There was less restrictive but non-random usage of the TcraJ and TcrbJ gene segments. Overall, the MBP-reacting T cell hybridomas from (B10.PL x PL/J)F1 mice were dominated by the MBP-reacting T cell pattern seen in B10.PL mice.

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.

Staphylococcal enterotoxin B induces arthritis in female DBA/1 mice but fails to induce activation of type II collagen-reactive lymphocytes

It has been proposed that superantigens are involved in the pathogenesis of autoimmune diseases. To test the possibility of superantigens inducing arthritis in naive mice, V beta 8-reactive superantigen staphylococcal enterotoxin B (SEB) was injected into naive mice. We used female DBA/1 mice, because they were susceptible to collagen-induced arthritis (CIA), in which the pathogenic T cells were supposed to preferentially use limited V betas of T cell receptors including V beta 8. Mild monoarthritis developed in uninjected hindlimbs of mice administered with SEB in higher frequency (an average incidence of 24%) than the control phosphate-buffered saline-injected mice (4.2%). Autoimmune responses in mice administered with SEB were compared with those in mice developing CIA. However, activation of type II collagen (IIC)-reactive T cells was not detected in SEB-injected mice. Production of autoantibodies, anti-IIC antibody and rheumatoid factor was also undetected. Although exact mechanisms of pathogenesis of this arthritis remain to be known, V beta 8+ T cells were activated for a long period and the unresponsiveness of V beta 8+ T cells was not detected in this strain. From these results, we discuss the pathogenesis of arthritis induced by SEB and the possibility that superantigen may play a role in the induction of autoimmune diseases.

In vivo the environmental pollutants lead and mercury induce oligoclonal T cell responses skewed toward type-2 reactivities

An oligoclonal utilization of Vbetas has been reported for pathogenesis of several autoimmune diseases, anti-tumorigenic activity, and superantigen-regulation of thymic T cell development. Altered ratios of Th1 and Th2 cells also are observed in immunodysregulations, leading to impaired cell-mediated immunity with an increased incidence of infectious disease or cancer and/or aberrant immunity that could culminate with an autoimmune disease. Lead (Pb) and mercury (Hg) are known pollutants with immunodisrupting activities; Hg is known to cause autoimmune glomerulonephritis. Both metals are known to suppress host resistance to pathogens. To further evaluate the manner by which these metals cause in vivo immunomodulation, their in vivo effects on Vbeta expression were evaluated along with the Th1 and Th2 frequency. Exposure of BALB/c mice to PbCl2 or HgCl2 induced an oligoclonal response with increases of Vbeta 5+, Vbeta 7+, and Vbeta 13+ CD4+ splenic, but not thymic, T cells. A significantly skewed frequency of Pb-induced splenic Th2 cells expressing Vbeta 7 or Vbeta 13 over Th1 cells was determined by limiting dilution analysis, but this Th2 predominance was not observed with CD4+ T cells expressing Vbeta 8. DO11.10 transgenic mouse exposed to Pb and antigen also demonstrated a skewed type-2 response evidenced by significantly increased IgE levels, lowered IFN-gamma levels, and increased IgG1 and lowered IgG2a anti-OVA levels. Even in the absence of specific T cell responses to a Pb-induced antigen, due to the restricted T cell specificity in the transgenic mouse model, Pb still was able to skew the response toward type-2 reactivity. However, this skewing occurred only in the presence of antigen. Therefore, the Pb-induced oligoclonal T cell response in BALB/c mice which must be initiated by self-antigens and was predominately type-2 may be responsible for autoantibody production and the detrimental health effects associated with Pb exposure.

Regulatory T cells specific for the same framework 3 region of the Vbeta8.2 chain are involved in the control of collagen II-induced arthritis and experimental autoimmune encephalomyelitis

Recent evidence indicates that chronic autoimmune disease can result from breakdown of regulation and subsequent activation of self-reactive T cells. In many murine autoimmune disease systems and in the Lewis rat, antigen-specific T cells utilizing the T cell receptor (TCR) Vbeta8.2 gene segment play a major role. In the myelin basic protein-induced experimental autoimmune encephalomyelitis (EAE) model in H-2(u) mice, we had shown that T cells recognizing a peptide determinant within the framework 3 region of the Vbeta8.2 chain have a critical role in influencing the course of the disease. Here, we report experiments in another disease system, collagen II (CII)-induced arthritis (CIA) in DBA/1LacJ (H-2(q)) mice, indicating a remarkably parallel control circuit to that found for EAE. A critical role is played by CII-specific Vbeta8.2-bearing T cells in the CIA system, which we have confirmed. Animals treated with the superantigen SEB before CII administration are significantly protected from CIA. Next, we tested the ability of peptides encompassing the entire Vbeta8.2 chain to induce proliferative responses. Only TCR peptide B5 (amino acids 76-101), a regulatory peptide in EAE, induced proliferation. B5 was then used to vaccinate DBA/1LacJ mice and was shown to reduce greatly the severity and incidence of CIA as measured by joint inflammation or histology. Furthermore, similar protection was found when B5 was administered after CII immunization. It was shown that there is physiological induction of a proliferative response to B5 during CIA and that the determinant within B5 is produced from a single chain TCR construct containing the entire Vbeta8.2 chain. Finally, the regulation of CIA is discussed in the context of other experimental autoimmune diseases, especially EAE, with emphasis on what appear to be strikingly common mechanisms.

T cell receptor (V beta) bias in the response of rheumatoid arthritis synovial fluid T cells to connective tissue antigens

T cell receptor (V beta) use in the response to type II collagen and cartilage proteoglycans was analysed in peripheral blood and synovial fluid T cells from RA patients. T cells from RA patients with an immune response to connective tissue antigens, and paired PB and SF samples were stimulated in vitro with type II collagen, high density aggrecan proteoglycans (PG), and the T cell mitogen concanavalin A. After short term culture, mRNA was extracted from cells and a reverse transcription-polymerase chain reaction was performed, using primers specific for eight TCR V beta determinants. Blood cells stimulated with ConA generated strong bands with virtually all the V beta primers tested, but the TCR (V beta) expression by SF T cells stimulated with mitogen was biased, suggesting a selection process during joint infiltration. The V beta phenotypes of cells responding to PG was restricted in individual RA patients, but the pattern of V beta use in the the RA population was not consistent. In contrast, the V beta phenotypes of SF cells responding to CII was highly biased in both individual patients and the RA population, with V beta 14, V beta 17, and V beta 8 phenotypes predominant. We conclude that the T cell response to connective tissue antigens is restricted compared with mitogen stimulation, with the highest degree of TCR bias seen in the response of SF T cells to stimulation with type II collagen.

Prevention and amelioration of collagen-induced arthritis by blockade of the CD28 co-stimulatory pathway: requirement for both B7-1 and B7-2

Collagen type II-induced arthritis (CIA) is an experimental model of arthritis that has been successfully used to dissect the pathogenesis of human rheumatoid arthritis and to identify potential therapeutic targets. We have used this model to evaluate the role of T cell co-stimulation in both disease development and progression. T cell co-stimulation is provided by ligation of CD28 with either B7-1 or B7-2 present on antigen-presenting cells and can be prevented by a soluble form of CTLA-4 (CTLA-4Ig) which binds with high affinity to both B7-1 and B7-2. We found that administration of CTLA-4Ig at the time of immunization prevented the development of CIA and was associated with lack of lymphocyte expansion within the draining lymph node and failure to produce anti-collagen IgG1 or IgG2a antibodies. To determine which CD28 ligand plays a more dominant role in CIA, we treated mice with monoclonal antibodies (mAb) against either B7-1 or B7-2. Neither anti-B7-1 nor anti-B7-2 had any effect on the course of CIA when given alone, but resulted in reduced incidence and clinical scores when given together. Interestingly, when treatment was delayed until after the onset of clinical disease, both CTLA-4Ig or anti-B7-1 plus anti-B7-2 mAb still ameliorated disease. Effective treatment was associated with a reduction in interferon-gamma production by lymph node cells following stimulation in vitro, suggesting that Th1 responses were diminished. This study points to a critical role of CD28 co-stimulation in the development and perpetuation of CIA in DBA/1 mice. Interestingly, it demonstrates an active role for T cells in the later stages of this disease and implicates both B7-1 and B7-2-mediated co-stimulation in the pathogenesis of CIA.

Immunization with T cell receptor V beta chain peptides deletes pathogenic T cells and prevents the induction of collagen-induced arthritis in mice

Collagen-induced arthritis (CIA) in susceptible strains of mice is an animal model of T cell-mediated inflammatory polyarthritis. Analysis of T cell receptor (TCR) V beta gene usage in cells isolated from arthritic joints of BUB/BnJ (BUB) mice (H-2q, TCR V beta a) showed that TCR V beta chain gene usage was limited to TCR V beta 3 and V beta 10 gene families. All of the BUB mice immunized with a mixture of TCR V beta 3 and TCR V beta 10 peptides, but not with control TCR V beta 14 peptide, were refractory to the induction of CIA. Immunization with TCR V beta 3 and V beta 10 peptides completely blocked the development of clinical and subclinical inflammation, formation of pannus and synovial hyperplasia, and the erosion of cartilage and bone. Further studies revealed that preimmunization of BUB mice with V beta 10 peptide alone was sufficient to render the mice resistant to CIA. Analysis of TCR V beta chain gene expression in lymph node cells from arthritic and arthritis-protected mice showed the expression of TCR V beta 10 subfamily in all of the arthritic mice, but not in arthritis-protected mice. Immunization with TCR V beta peptides did not diminish the humoral responses to chicken type-II collagen and also elicited significant levels of anti-V beta 3 and anti-V beta 10 peptide antibodies. Antibodies cross-reactive with mouse chicken type-II collagen were detected in both the arthritic and arthritis-protected mice. Adoptive transfer of serum from arthritis-protected BUB mice significantly delayed the onset (P < 0.005) of arthritis in recipient BUB mice. In contrast, mice injected with serum from arthritic mice had early onset of arthritis. These results demonstrate that immunization of BUB mice with TCR V beta chain peptides elicited antibodies reactive with the self-TCR and prevented the induction of collagen-induced arthritis by eliminating or downregulating pathogenic T cells and consequently blocking the development of humoral immune response. These findings may have clinical applications in treating human autoimmune diseases characterized by common TCR gene usage.

Limited heterogeneity in T-cell receptor V beta chain gene expression in arthritic joints of BUB/BnJ (H-2q) mice--a T-cell receptor V beta a strain

We have earlier shown that T-cells in arthritic joints and LNs of B10.Q mice (H-2q, TCR V beta b) use a restricted number of TCR V beta chain genes (V beta 6, 8, 9). In the present study, we have investigated the TCR V beta chain gene expression in arthritic joints and LN of BUB/BnJ mice (H-2q, TCR V beta a). Mice were immunized with [table: see text] chicken type-II collagen, and arthritic joints and draining LNs were removed at the onset of arthritis and the TCR V beta chain gene expression was studied by PCR. A restricted usage of TCR V beta was observed in both the tissues. A dominant usage of TCR V beta 4, 7, and 15 was found in the LNs while TCR V beta 3 and 10 were predominantly expressed in arthritic joints in the majority of the arthritic mice (5/7). Our results indicate that (a) in H-2q mice with CIA there is a restricted usage of TCR V beta chain genes regardless of the TCR V beta genotype; and (b) in the absence of TCR V beta 8 and 9, TCR V beta 3 and 10 are predominantly used by joint-infiltrating T-cells.

Altered development of collagen induced arthritis in T cell receptor V beta congenic B10.RIII mice

Analysis of the mouse T cell receptor (TCR) V beta genome has revealed the existence of two distinct genotypes which bear deletions of certain V beta genes. Mice bearing the V beta a genotype lack approximately 50% of the V beta genome while V beta c mice lack 70% of the known V beta genes. Studies of the experimental model collagen induced arthritis (CIA) have indirectly suggested that the presence of truncated V beta genotypes may influence susceptibility to this autoimmune disease. In order to confirm the influence of V beta a and V beta c genotypes on CIA, we derived mice congenic for the known V beta haplotypes in the CIA susceptible B10.RIII (H-2r) background. Flow cytometric analysis of splenic lymphocytes revealed normal T cell levels in both B10.RIII-V beta congenic lines. Expectedly, a generalized increase in the expression of some non-deleted V beta genes was detected. In addition, the mice were immunized with porcine type II collagen and monitored for CIA. B10.RIII-V beta a mice showed little difference in arthritis incidence or severity versus B10.RIII, but a significant delay in the onset of CIA was seen. In contrast, B10.RIII-V beta c mice showed a marked decrease in arthritis incidence versus B10.RIII and the severity of CIA in arthritic mice was also significantly lower (p < 0.01). Thus, in the B10.RIII strain, the presence of truncated TCR V beta genotypes alters the development of CIA. These findings may shed light on the influence of TCR genotypes in the induction and development of human rheumatoid arthritis.

Restricted expression of T cell receptor V beta and lymphokine genes in arthritic joints of a TCR V beta a (H-2q) mouse strain-BUB/BnJ-with collagen-induced arthritis

Type II collagen-induced arthritis (CIA) is an animal model of inflammatory polyarthritis with clinical and pathological features resembling rheumatoid arthritis (RA). We compared the expression of T cell receptor (TCR) V beta genes in T cells isolated from the inflamed joints, draining lymph nodes and the spleens of BUB/BnJ (H-2q) mice (BUB) during the early phase of CIA. We also investigated the profiles of cytokine gene expression in T cells obtained from the same tissues. We found that the expression of TCR V beta s, in arthritic joints of mice, during the early phase of the disease was limited to TCR V beta 3 and 10 gene families. In contrast, TCR V beta 4, 7, and 15 were predominant in the draining lymph nodes (LNs) and TCR V beta 2, 6, and 14 were predominant in the spleens of arthritic mice. Molecular cloning and sequence analysis revealed that the T cell populations in the arthritic joints were oligoclonal as determined by the limited N-D-N region diversity observed in the sequenced clones. These results demonstrate, for the first time, that (1) joint infiltrating T cells in TCR V beta a genotype mice use a restricted repertoire of TCR V beta genes; (2) there was oligoclonal expansion of infiltrating T cells in arthritic joints in mice with collagen-induced arthritis. Our results on cytokine gene expression in the arthritic joints of BUB mice indicate that Th-1-like T cell derived cytokines may be the predominant cytokines in the arthritic joints as illustrated by the presence of transcripts for IL-2 and IFN-gamma but not IL-4. In summary, our results provide evidence that T cells with restricted specificities, and more specificially, Th-1 type T cells, are crucial in the early phase of collagen induced arthritis in mice.

Transfer of experimental antiphospholipid syndrome by bone marrow cell transplantation. The importance of the T cell

OBJECTIVE

To investigate the potential of bone marrow cells from mice with primary antiphospholipid syndrome (APS) to transfer the disease to naive mice, and to determine the importance of the role of T cells in the APS.

METHODS

Experimental primary APS was induced in naive mice following active immunization with anticardiolipin (aCL) monoclonal antibody (MAb). Whole-population or T cell-depleted bone marrow cells from mice with experimental primary APS were infused into total body-irradiated naive BALB/c recipients.

RESULTS

Bone marrow cells (in the presence of T cells) had the potential to induce experimental APS in naive mice, which resulted in high serum titers of aCL, antiphosphatidylserine, and antiphosphatidylinositol antibodies; an increased number of antibody-forming cells specific for each of the above phospholipids; a positive lymph node cell proliferative response to aCL MAb; and clinical features of primary APS, including thrombocytopenia, prolonged activated partial thromboplastin time (indicating the presence of lupus anticoagulant), and a high frequency of fetal resorptions (the equivalent of human fetal loss). T cell-depleted bone marrow cells did not transfer the disease.

CONCLUSION

This study demonstrates the important role of T cells in the development and transfer of experimental primary APS and raises the possibility of T cell manipulations in treatments to prevent this condition.

T cell regulation of collagen-induced arthritis in mice. III. Is T cell vaccination a valuable therapy?

Since T cells play a critical role in collagen-induced arthritis (CIA), CD4+ T cell hybridomas were derived from DBA/1 mice immunized with bovine type II collagen (CII). The hybrid clones selected were Thy-1-2+, CD4+, CD8-, T cell receptor (TcR) alpha beta + and produced interleukin-2 in response to CII peptides presented by I-Aq molecules. The clones were collagen type-specific and recognized CII from many species except the mouse. More precisely, the reactivity was directed against the immunodominant cyanogen bromide-cleaved fragment CB11(II). Analysis of the TcR carried by the T cell hybridomas showed that they used identical V alpha and J alpha (V alpha BMB, J alpha 20) gene segments and two distinct V beta (V beta 1 and V beta 4) associated with the J beta 2.5 gene segment. Interestingly, the junctional regions were highly conserved in structure and length. These findings may indicate a strong in vivo selection by the antigen for a particular combination of both alpha and beta chains of the TcR. Inoculation of irradiated anti-CII T cell hybrids into DBA/1 mice, before priming with CII, altered the course of the disease resulting in either a long-lasting suppression or an exacerbation of CIA whereas a control CD4+ hybridoma with an unrelated specificity did not influence the development of arthritis. However, the regulatory effect of anti-CII T cell clones was unpredictable, suggesting that the TcR structure may not solely account for the modulation of CIA and that T cell vaccination is not a reliable method for inducing suppression of CIA.

HLA-linked rheumatoid arthritis

Twenty-eight pedigrees were ascertained through pairs of first-degree relatives diagnosed with rheumatoid arthritis (RA). RA was confirmed in 77 pedigree members including probands; the absence of disease was verified in an additional 261 pedigree members. Pedigree members were serologically typed for HLA. We used likelihood analysis to statistically characterize the HLA-linked RA susceptibility locus. The genetic model assumed tight linkage to HLA. The analysis supported the existence of an HLA-linked RA susceptibility locus, estimated the susceptibility allele frequency as 2.16%, and estimated the lifetime penetrance as 41% in male homozygotes and as 48% in female homozygotes. Inheritance was recessive in males and was nearly recessive in females. In addition, the analysis attributed 78% of the variance within genotypes to genetic or environmental effects shared by siblings. The genetic model inferred in this analysis is consistent with previous association, linkage, and familial aggregation studies of RA. The inferred HLA-linked RA susceptibility locus accounts for approximately one-half of familial RA, although it accounts for only approximately one-fifth of the RA in the population. Although other genes may account for the remaining familial RA, a large portion of RA cases may occur sporadically.

A genetically determined insertion/deletion related polymorphism in human T cell receptor beta chain (TCRB) includes functional variable gene segments

Polymorphism in the human T cell receptor beta chain (TCRB) gene complex includes haplotypes with different numbers of TCRBV genes. An insertion/deletion related polymorphism (IDRP) in the human TCRBV region was found to involve TCRBV gene segments. Inserted TCRB haplotypes contain an additional 21.5 kb in which three TCRBV genes are encoded, members of the TCRBV7, TCRBV9, and TCRBV13 families. Two TCRBV gene segments were present only in inserted haplotypes; one of these, TCRBV7S3, is a functional gene and the other, TCRBV9S2(P), is a pseudogene because of an inframe termination colon. In addition, inserted haplotypes contain two identical copies of the TCRBV13S2 gene, whereas deleted haplotypes have only one copy. Deleted haplotypes could be subdivided into two types, deleted*1 and deleted*2, on the basis of sequence variations in TCRBV6S7 and TCRBV13S2 genes. Both deleted*1 and deleted*2 haplotypes contained the same number of TCRBV genes; both contain 60 genes of which 50 are functional, whereas, inserted haplotypes contained 63 genes of which 52 are functional. Comparisons of inserted region sequences with the homologous region in a deleted haplotype, and with sequences surrounding related TCRBV genes, revealed patterns of similarity that suggest insertion as well as deletion events have occurred in the evolution of the TCRBV gene complex. These data indicate that the genomic TCR repertoire is expanded in individuals who have inserted TCRBV haplotypes. The presence of additional TCRBV genes or, alternatively, the absence of certain TCRBV genes may have an impact upon immune responses and susceptibility to autoimmune diseases.

Collagen-induced arthritis in T cell receptor V beta congenic B10.Q mice

B10.Q (H-2q) mice congenic for the truncated T cell receptor (TCR) V beta a and V beta c haplotypes were derived to examine the influence of TCR V beta genomic deletions in murine collagen-induced arthritis (CIA). Previous studies using gene complementation and segregation analyses suggested that in SWR (H-2q) mice, possession of the V beta a gene deletion results in CIA resistance. However, other studies have suggested alternative hypotheses. Thus, analysis of TCR V beta congenic mice allows for direct examination of V beta genotypes in CIA control. After immunization with bovine type II collagen, B10.Q-V beta a mice showed no difference in arthritis susceptibility, onset, or severity when compared with prototype B10.Q mice. In contrast, B10.Q-V beta c mice, which lack the V beta 6, 15, 17, and 19 families in addition to the V beta a deletion, were highly resistant to CIA. In vivo depletion of V beta 6+ T cells in B10.Q-V beta a mice significantly delayed arthritis onset suggesting that, among those V beta genes present in V beta a but absent in V beta c, V beta 6+ T cells contribute to arthritogenesis. Our findings show that, in B10.Q-V beta congenic mice, while the V beta a genotype does not prevent CIA, the highly truncated V beta c genotype renders B10.Q mice resistant to CIA. Thus, deletions within the V beta TCR genome can indeed influence CIA and suggests that the TCR repertoire displays only marginal flexibility in response to arthritogenic stimuli.

Analysis of the V beta specificity of superantigen activation with a rapid and sensitive method using RT PCR and an automatic DNA analyser

Polymerase chain reaction (PCR) by the specific amplification of a DNA target sequence has been shown to permit analysis of T cell receptor usage. The complete repertoire is amplified using oligonucleotide primers specific for each of the known V alpha or V beta regions of the T cell receptor. One of the methods currently used to appreciate the relative quantity of different V chains of the TCR is by coamplifying in the same reaction tube the variable region of one chain together with the constant region of the other chain. We have optimised PCR conditions and analysed PCR products on an automatic DNA analyser facilitating the quantification of the amplified products, avoiding the use of radioisotopes, and allowing the determination of the sizes of CDR3 regions, thus giving new information on the modification of the T cell repertoire. This method was used to analyse the precise V beta specificity of the T cell activation with the superantigen SEB.

T-cell antigen receptors in rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic disease of unknown etiology characterized by chronic inflammation mainly in the joints. Several lines of evidence suggest that T cells are involved in the pathogenesis of the disease. RA is associated with certain HLA-DR alleles. Studies analyzing T-cell receptor transcripts in RA have found biased or preferential usage of certain V alpha and/or V beta gene segments by T cells infiltrating the synovial membrane or extravasating into the synovial fluid compared to peripheral blood. In certain patients few T-cell antigen receptor (TCR) clones dominated the infiltrating T cells, suggesting that T cells from the synovial membrane or the synovial fluid comprise oligoclonal populations of T cells. However, other studies have found a polyclonal population of T cells. In interpreting these results the phase of the disease (early vs. late RA), the source of T cells and the limitations of the methods used in these studies should be taken into consideration. However, it appears that synovial T cells comprise oligoclonal populations of T cells and that there is a bias towards particular TCR gene segments, although a specific TCR gene segment in RA has not emerged.