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In several human T-cell-mediated autoimmune diseases and animal models of such illnesses, T-cell receptors (TCR) specific for antigens that initiate or perpetuate the disease share a limited number of variable region determinants. Vaccinations with peptides derived from over-represented TCRs are effective treatment for some of these disorders. RA is a chronic inflammatory disease in which there is prominent T-cell infiltration in the synovial lining layer. TCR V beta 3, V beta 14, and V beta 17 have been found to be over-represented among IL-2 receptor-positive T-cells from patients with RA. A phase II clinical trial in RA, using a combination of three peptides derived from V beta 3, V beta 14, and V beta 17, has yielded promising results. Larger clinical efficacy and safety studies must be performed to determine if TCR peptide vaccination will become a viable treatment alternative for patients with RA.  相似文献   

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OBJECTIVE: To evaluate radiologic progression in patients with early rheumatoid arthritis (RA) receiving methotrexate (MTX) as the first slow acting drug. METHODS: An open, prospective study of 29 patients with RA (21 F, 8 M, mean age 48.5+/-15.4 yrs). The mean duration of RA was 6.6 (2-60) months; and rheumatoid factor was present in 11 cases. Clinical, biological, and radiographic evaluations were done before the start of MTX treatment and after 13+/-3.8 months. Radiographs of hands and wrists were blindly studied by 2 physicians, using Larsen's and modified Sharp's methods. There was a significant correlation for the scores of the 2 physicians evaluated by kappa coefficient. Radiographic evolution was defined as an increase of 15 points in the radiologic score by each method used. RESULTS: Patients showed significant clinical improvement after one year of MTX treatment. Despite clinical and biological improvement, significant mean radiographic progression was noted, with Larsen's method (p = 0.001) and Sharp's method (p = 0.034), without reaching the maximum score. However, using the definition of radiographic progression, the radiologic scores indicated stabilization in 23 patients with Larsen's method and in 24 patients with Sharp's method. CONCLUSION: This study revealed mild radiographic progression in early RA patients treated with MTX for one year. Further controlled studies are needed.  相似文献   

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Cognate interaction between TCRs and MHC class II molecules plays an important role in initiating the allergen-specific immune response. Therefore, we analyzed the TCR distribution of human PBLs of 56 atopic and nonatopic (NA) individuals, including 4 monozygotic twin pairs, from two extended and four nuclear families. The expression of 23 V beta and 3 V alpha elements was analyzed. The blood samples of symptomatic birch pollen-sensitized individuals that were taken < or = 6 wk after the birch pollen season (n = 8) showed a significantly higher frequency of V beta 16.1+ and V beta 20.1+ T cells compared with the blood samples of birch pollen-sensitized individuals that were obtained out of allergen season (n = 10) or from NA individuals (p < 0.0005 and p < 0.0001, respectively). Allergen-specific lymphocyte proliferation was detected in the allergic individuals, and the distribution of V beta 16.1+ and V beta 20.1+ T cells returned to normal levels after the pollen season. The frequency of these V beta-expressing T cells correlated with the levels of allergen-specific IgE Abs. In addition, cat-sensitized individuals (n = 8) showed a significantly higher frequency of V beta 17.1-expressing T cells than did NA individuals (p < 0.005). Our results indicate restricted TCR-V beta gene usage in cat and birch pollen allergies; we suggest that both genetic and environmental factors contribute to TCR-V beta gene expression and to the development of a specific T cell response.  相似文献   

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Population-based genetic associations have been reported between RFLPs detected with probes corresponding to the genes encoding the beta chain of the T-cell receptor for antigen (TCRB) and a variety of autoimmune disorders. In the case of multiple sclerosis (MS), these studies have localized a putative disease-associated gene to a region of approximately 110 kb in length, located within the TCRB locus. In the current study, all 14 known TCRBV (variable region) genes within the region of localization were mapped and identified. The nucleotide sequences of these genes were determined in a panel of six MS patients and six healthy controls, who were human-leukocyte antigen and TCRB-RFLP haplotype matched. Nine of the 14 TCRBV genes studied showed evidence of polymorphism. PCR-based assays for each of these polymorphic genes were developed, and allele and genotype frequencies were determined in a panel of DNA samples from 48 MS patients and 60 control individuals. No significant differences in allele, genotype, or phenotype frequencies were observed between the MS patients and controls for any of the 14 TCRBV-gene polymorphisms studied. In light of the extensive linkage disequilibrium across the region studied, the saturating numbers of polymorphisms examined, and the direct sequence analysis of all BV genes in the region, these results suggest that it is unlikely that germ-line polymorphism in the TCRBV locus makes a major contribution to MS susceptibility.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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OBJECTIVES: To investigate the prognostic significance of clinical and genetic markers on the outcome of patients with recent-onset rheumatoid arthritis (RA) treated actively with slow acting antirheumatic drugs (SAARDs). METHODS: A total of 142 consecutive patients with early RA (median disease duration of 7 months) were treated according to the "sawtooth" strategy and prospectively followed up for an average of 6.2 years. Several clinical parameters at start as well as genetic markers were related to the functional outcome (ARA Functional class and HAQ disability score) and radiographic joint damage (Larsen's score) at the latest visit. RESULTS: In logistic regression analysis only Mallya score (including morning stiffness, pain scale, grip strength, Ritchie's articular index, haemoglobin, and erythrocyte sedimentation rate) at baseline, and Mallya score and rheumatoid factor (RF) positivity at one year were found to be of significance with respect to the radiographic outcome of the patients. Furthermore, at the latest visit HAQ score was related to radiographic score. At baseline the mean ages of the DR4 positive patients and the patients with RA associated DR alleles were statistically significantly lower than those without the above mentioned risk factors (44 v 49, p = 0.03 and 41 v 53, p = 0.04, respectively). However, these genetic markers had no prognostic significance on the functional or radiographic outcome of the patients. CONCLUSION: High clinical disease activity at baseline and RF positivity especially at one year after the institution of SAARD treatment are the best predictors of poor prognosis in early RA. However, from the clinical point of view, the disease outcome of an individual patient with early RA, cannot be predicted accurately enough by present means.  相似文献   

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In order to explore the expression and regulation of T3 receptor genes, the relative amount of peripheral lymphocytes c-erbA alpha and c-erbA beta mRNA from patients with Graves disease and Hashimoto thyroiditis with hypothyroidism (HTH) was determined with hybridization by using human c-erbA alpha and c-erbA beta probes. The results showed that there were two types of c-erbA alpha mRNA (6.0 kb, 3.2 kb) and three types of c-erbA beta mRNA (5.0 kb, 3.0 kb, 2.0 kb). The levels of c-erbA alpha and c-erbA beta mRNA were found to increase in HTH patients, but unaltered in Graves disease patients. This result suggests the presence of up-regulation of nuclear T3 receptor at the gene level in the lymphocytes of hypothyroid patients. The high level of c-erbA alpha and c-erbA beta mRNA may contribute in part to the increase in T3 receptor.  相似文献   

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OBJECTIVE: To investigate the long-term radiographic course as a mathematical function of disease duration in individual patients and in a group of patients with rheumatoid arthritis (RA). METHODS: In 109 patients with RA, radiographic examinations of 46 diarthrodial joints were performed at regular intervals of 1-3 years, for up to 30 years after disease onset. RESULTS: Five main types of progression were identified: 1) a rare type (<1%), with no radiographic progression at all; 2) a type with a slow or moderate onset, but an increasing progression rate (9% exponential growth type and 30% linear type); 3) a type with a moderate-to-fast onset and a stable progression rate (the square-root type; 11%); 4) a type with a fast onset, but a later decreasing progression rate (the first-order kinetics type, 30%); and 5) a type characterized by slow onset, then acceleration and later deceleration (the sigmoid type, 20%). CONCLUSION: The progression of radiographic damage in RA followed mathematical functions of time. The identification of progression type may be used in the prediction of outcome in patients with RA.  相似文献   

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beta 2-Microglobulin knockout mice (beta 2-m-/-) with MHC class I expression deficiency are able to develop functional TCR(+)-alpha beta, CD8+ CTLs in response to tumor cell injection. The i.p. injection of beta 2-m-/- mice with tumor results in the massive accumulation of highly lytic CD8+ CTLs in the peritoneum and causes the local recruitment of CD8+ T cells into lymph nodes and spleens of immune animals. The accumulation of CD8+ CTLs in peritoneum is accompanied by the rejection of tumor cells and the survival of animals. The deficiency in MHC class I expression in beta 2-m/- mice is reflected in the delayed tumor rejection and CD8+ cell accumulation during the primary anti-tumor response in comparison with normal mice. The secondary response, however, is identical in normal and MHC class I-deficient mice. The rejection of tumor cells appears to be MHC class I directed because no rejection of tumors, no accumulation of CD8+ CTLs, and no survival of animals were observed when syngeneic tumor cells were used for injection with the notable exception of anti-minor Ag response. The Ag specificity of CD8+ CTLs in beta 2-m-/- mice is demonstrated using a panel of tumor target cells and class I transfectants. Although no substantial differences were found in the number and specificity of peritoneal CD8+ CTLs in beta 2-m-/- and normal mice using tumor rejection studies, the analysis of TCR-V beta phenotype using the panel of mAbs revealed the reduction in proportion of TCR-V beta 5 and TCR-V beta 6 used by CD8+ cell population from beta 2-m-/- mice. Development of lytic and H-2-directed CD8+ cells in regional lymph nodes was also observed after footpad immunization of beta 2-m-/- mice with TNP-labeled C57BL/6 splenocytes, suggesting anti-minor Ag reaction.  相似文献   

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A number of human TCR V beta gene segments are reported to be polymorphic, with alleles differing by one or a small number of amino acid substitutions. In the absence of detailed structural information regarding the interaction of specific positions in the TCR with Ag or MHC, the significance of such variation is difficult to assess. In this report the relative use of the two common alleles of the human V beta 6.7 gene, 6.7a and 6.7b, which differ by two non-conservative amino acid substitutions, and the use of two common alleles of the V beta 12.2 gene, which differ by only silent substitutions, were measured in PBL derived from individuals heterozygous for these alleles. Equal use of V beta 12.2 alleles was observed, consistent with the inability of selection mechanisms to discriminate between the products of these alleles that are indistinguishable at the amino acid level. However, statistically significant skewing in the use of V beta 6.7 alleles was observed in 15 of 16 individuals studied. Expression levels for each allele ranged from 16 to 84% of the total V beta 6.7 signal in heterozygous individuals, with either the 6.7a or the 6.7b allele predominant in different individuals. Based on segregation studies in families, it seems unlikely that other unidentified polymorphism in the TCR beta locus, such as in the V beta 6.7 promoter, was responsible for the differential allele expression. Family studies provided no evidence for an association between specific HLA haplotypes and V beta 6.7 allele use. These results indicate that even modest allelic variation in human TCR V beta coding regions can have a significant impact on the expression of human V beta genes in the peripheral repertoire.  相似文献   

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Beh?et's disease (BD) has been known to be strongly associated with the human leukocyte antigen (HLA) B51. This B51 association has been confirmed in many different ethnic groups between the Middle East and Japan, and it has been proposed that BD is prevalent in those ethnic groups along the old Silk Route. The hypothesis could be made that B51 molecules are primarily involved in BD development through specific antigen presentation. However, polymorphic analyses of the TNFB gene and Tau-a microsatellite between the HLA-B and TNF genes indicate that the pathogenic gene of BD is not the HLA-B51 gene itself but another gene located around the HLA-B gene. HLA-C genotyping by the PCR-SSP method also suggests that the BD pathogenic gene is not the HLA-C gene itself but other gene located near the HLA-B gene. Recently we sequenced a single contig of 236,822 bp from the MICA gene (58.2 kb centromeric of HLA-B) to 90.8 kb telomeric of HLA-C and identified 8 novel genes designated NOB1-8 (NOB: new organization associated with HLA-B). During the course of the genomic sequence analysis we clarified the genetic structure of the MICA (MHC class I chain-related gene A) gene and found a triplet repeat microsatellite polymorphism of (GCT/AGC)n in the transmebrane (TM) region. Furthermore, the microsatellite allele consisting of 6 repetitions of GCT/AGC (MICA A6 allele) was present at a significantly higher frequency in the BD patient group than in the control group and a significant fraction of B51-negative patients were positive for this MICA A6 allele. These results suggest the possibility of a primary association of BD with MICA rather than HLA-B.  相似文献   

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The generation of a productive "in-frame" T cell receptor beta (TCR beta), immunoglobulin (Ig) heavy (H) or Ig light (L) chain variable region gene can result in the cessation of rearrangement of the alternate allele, a process referred to as allelic exclusion. This process ensures that most alphabeta T cells express a single TCR beta chain and most B cells express single IgH and IgL chains. Assembly of TCR alpha and TCR gamma chain variable region genes exhibit allelic inclusion and alphabeta and gammadelta T cells can express two TCR alpha or TCR gamma chains, respectively. However, it was not known whether assembly of TCR delta variable regions genes is regulated in the context of allelic exclusion. To address this issue, we have analyzed TCR delta rearrangements in a panel of mouse splenic gammadelta T cell hybridomas. We find that, similar to TCR alpha and gamma variable region genes, assembly of TCR delta variable region genes exhibits properties of allelic inclusion. These findings are discussed in the context of gammadelta T cell development and regulation of rearrangement of TCR delta genes.  相似文献   

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Globoid cell leukodystrophy (GLD) of Krabbe disease results from mutations in the galactocerebrosidase (GALC) gene. Previously, we had identified a large deletion in the GALC gene together with a C to T polymorphism at cDNA position 502 in a significant number of cases of infantile Krabbe disease; however, the deletion breakpoint had not been found. In this paper we show that the deletion is approximately 30 kb starting near the middle of the 12 kb intron 10, and includes all of the coding region through exon 17 plus an additional 9 kb. The deletion junction contains a 4 bp direct repeat and is preceded by sequence identified as belonging to the Alu family of interspersed repetitive elements. Using genomic DNA and a PCR-based test to detect normal and deleted sequences at that location, a large number of patients with all clinical types of GLD were analyzed. Of 21 infantile patients found to be heterozygous for the 502T polymorphism reported previously, 15 had the deletion, one could not tested and five, including a Hmong child, did not have the deletion. Sixteen other infantile patients previously tested were found to be either homozygous (10) or heterozygous (6) for the deletion. In addition, five patients with juvenile and adult GLD were found to be heterozygous for the deletion. In every case tested, the deletion was always found on the same allele as the 502T polymorphism. However, other disease-causing mutations have been found on the 502T allele. With careful genotype analysis these families can receive improved genetic information including patient and carrier identification and preimplantation diagnosis.  相似文献   

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There is a strong genetic influence on the susceptibility to celiac disease. Although in the vast majority of patients with celiac disease, the HLA-DQ(alpha1*0501, beta1*0201) heterodimer encoded by the alleles HLA-DQA1*0501 and HLA-DQB1*0201 seems to confer the primary disease susceptibility, it cannot be excluded that other genes contribute to disease susceptibility, as indicated by the difference in concordance rates between monozygotic twins and HLA identical siblings (70% vs. 30%). Obviously other genes involved in the genetic control of T cell mediated immune response could potentially influence susceptibility to celiac disease. The density of T cells using the gammadelta T cell receptor (TCR) is considerably increased in the jejunal epithelium of patients with celiac disease, an abnormality considered to be specific for celiac disease. This suggests an involvement of gammadelta T cells in the pathogenesis of the disease. To ascertain whether the TCR delta (TCRD) gene contributes to celiac disease susceptibility we carried out an association study and genetic linkage analysis using a highly polymorphic microsatellite marker at the TCRD locus on chromosome 14q11.2. The association study demonstrated no significant difference in allele frequencies of the TCRD gene marker between celiac disease patients and controls; accordingly, the relative risk estimates did not reach the level of statistical significance. In the linkage analysis, performed in 23 families, the logarithm of the odds (LOD) scores calculated for celiac disease versus the TCRD gene marker excluded linkage, suggesting that there is no determinant contributing to celiac disease status at or 5 cM distant to the analyzed TCRD gene marker. In conclusion, the results of the present study provide no evidence that the analyzed TCRD gene contributes substantially to celiac disease susceptibility.  相似文献   

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OBJECTIVE: To describe the longitudinal radiographic course of rheumatoid arthritis (RA), and to identify and quantitate predictors of radiographic progression. METHODS: This prospective, longitudinal study of radiographic progression and clinical predictors of RA involved 256 patients with RA who were seen within the first 2 years of disease (mean 0.77 years) and were followed up for up to 19 years. Participants underwent a total of 6,278 clinical assessments (mean 24.5) and 934 paired radiographs (mean 3.1, range 2-6). Clinical assessments at every visit included determination of the erythrocyte sedimentation rate (ESR), grip strength, pain scores, tender joint counts, and anxiety and depression measurements. Regression analyses utilized time-integrated predictors. RESULTS: Overall, radiographic progression rates, as measured by the summary Sharp scores, appeared constant over the course of RA. The strongest correlate of progression was the time-integrated ESR (rho=0.53). This association grew stronger with time. At 0-5 years, 5-10 years, 10-15 years, and 15-20 years, correlations were 0.40, 0.50, 0.65, and 0.74, respectively, and for the period 10-20 years, the correlation was 0.67. In multivariate models, the mean ESR, mean grip strength, rheumatoid factor positivity, and tender joint count were independent predictors of radiographic progression. CONCLUSION: Radiographic damage occurs at a constant rate in RA, and is not greater early in RA or reduced later in the course of the illness. Acute-phase reactants are, by far, the strongest determinants of progression.  相似文献   

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In this study we have analyzed the TCR V alpha and V beta regions at the DNA level in the CD4+CD45RO+ memory T cell population of synovial tissue infiltrating T lymphocytes of three rheumatoid arthritis (RA) patients and one patient with chronic arthritis. Cell lines of CD4+CD45RO+, CD4+CD45RO-, CD8+CD45RO+ and CD8+CD45RO- T lymphocyte populations were generated following FACS cell sorting of freshly isolated synovial tissue mononuclear cell infiltrates (STMC) and of freshly isolated peripheral blood mononuclear cells (PBMC) of these patients. The phenotypic and molecular analyses have revealed the following. (i) The TCR repertoires of tissue infiltrating T lymphocytes in the various subsets were extensive on the basis of TCR V gene family usage. (ii) Furthermore, each patient displayed individual specific TCR V gene expression patterns in the various STMC and PBMC derived T cell subsets. However, the majority of these arthritis patients manifested increased expression of multiple TCR V gene families in the synovial tissue derived CD4+CD45RO+ T cell population when compared with the peripheral blood derived CD4+CD45RO+ subset. Of these gene families, we found enhanced expression of the TCR V alpha 7 and V beta 11 gene segments in synovial tissue to be shared by all four patients analyzed. (iii) Nucleotide sequence analysis of the CDR3 regions of a number of TCR V regions in the CD4+CD45RO+ T cell subsets has revealed that the CDR3 regions comprised within synovial tissue derived TCR V regions differed from those found in peripheral blood derived TCR V regions. These differences in CDR3 diversity might be the consequence of a specific interaction with particular MHC-peptide complexes expressed at the site of inflammation. (iv) The CDR3 region analysis also showed individual specific amino acid motifs within the N-D-N regions of all analyzed TCR V beta genes derived from PBMC as well as STMC.  相似文献   

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