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At least 685 records · Page 38Linked to original sources
PubMed1990

HLA antigens in juvenile arthritis. Pauciarticular and polyarticular juvenile arthritis are immunogenetically distinct.

Using DNA techniques, we investigated the role of HLA-DR, DQ, and DP alleles in susceptibility to juvenile arthritis (JA). We studied 2 groups of patients with JA having a different disease prognosis and course. The pauciarticular form is usually benign, while the polyarticular disease frequently leads to joint destruction and disability. Persistent pauciarticular disease developed preferentially in patients having HLA-DRw13-Dw18 and DQw6-Dw18, but these antigens did not confer susceptibility in patients whose disease converted to the polyarticular form. HLA-DPw2.1 was an additional susceptibility factor for patients with JA of pauciarticular onset. In the polyarticular form of JA, HLA-DPw3 was the major factor for susceptibility, giving a relative risk of 10.3 (P less than 0.0001). In addition, we found that DRw8.1 and DQw4 were increased, and HLA-DR4 was markedly decreased, in patients with pauciarticular and polyarticular disease. These results indicate that in addition to some shared factors, distinct HLA class II alleles are important in pauciarticular or polyarticular JA. We conclude that typing with oligonucleotide probes may be useful in predicting the outcome in some children with arthritis.

Adolescent↗
PubMed1994

The large granular lymphocyte syndrome with rheumatoid arthritis. Immunogenetic evidence for a broader definition of Felty's syndrome.

OBJECTIVE: To assess whether the HLA-DR4 association found in rheumatoid arthritis (RA) is also seen in the large granular lymphocyte (LGL) syndrome. METHODS: HLA-DR genotyping was performed using restriction fragment length polymorphism and polymerase chain reaction analysis. RESULTS: LGL syndrome patients with RA showed the same HLA-DR4 association seen in RA/Felty's syndrome (FS), while LGL syndrome patients without arthritis did not. CONCLUSION: It is proposed that FS and the LGL syndrome represent different variants of a broader syndrome comprising RA, neutropenia, LGL expansions, HLA-DR4 positivity, and splenomegaly.

Adult↗
PubMed1995

HLA type as a predictor of mixed connective tissue disease differentiation. Ten-year clinical and immunogenetic followup of 46 patients.

OBJECTIVE: To determine any clinical or genetic markers of differentiation and outcome in a previously described cohort of 46 patients with mixed connective tissue disease (MCTD). METHODS: Patients were clinically evaluated, chart notes reviewed, and HLA subtyping and immunology profiles performed where possible. Eleven had died and 7 were lost to followup. RESULTS: MCTD had differentiated into systemic lupus erythematosus in 12 patients and into systemic sclerosis in 13. The latter was associated with HLA-DR5 (P = 0.038), and nondifferentiation was associated with HLA-DR2 or DR4 (P = 0.007). Three HLA-DR4 positive patients had MCTD that evolved into rheumatoid arthritis. Erosive and/or deforming arthritis was associated with HLA-DR1 or DR4 (P = 0.015). HLA-DR3 was associated with interstitial lung fibrosis (P = 0.044) and keratoconjunctivitis sicca (0.001 < P < 0.01). Severe Raynaud's phenomenon predicted higher mortality (0.01 < P < 0.05). CONCLUSION: We suggest that MCTD is, for most patients, an intermediate stage in a genetically determined progression to a recognized connective tissue disease. Those whose disease remains undifferentiated might be considered a distinct subset.

Adolescent↗
PubMed1996

The coexistence of systemic sclerosis and rheumatoid arthritis in five patients. Clinical and immunogenetic features suggest a distinct entity.

To elucidate the clinical characteristics and pathogenesis of scleroderma-rheumatoid arthritis (SSc-RA) overlap syndrome, we analyzed the clinical features of 5 patients with SSc-RA overlap. Their HLA phenotypes and genotypes were also determined. Generalized skin sclerosis, severe seropositive polyarthritis, pulmonary fibrosis, anti-topoisomerase I antibodies, and HLA-DR4,53;DQA1*0301;DBQ1*04 haplotype were observed in all of the patients. Similar clinical features were recognized in most of the 10 cases reported previously. Our case studies indicate that SSc-RA overlap may be a distinct entity.

Aged↗
PubMed1996

Autoantibodies to fibrillarin in systemic sclerosis (scleroderma). An immunogenetic, serologic, and clinical analysis.

OBJECTIVE: To determine the frequency, clinical associations, and any major histocompatibility complex correlations of antifibrillarin antibodies in patients with systemic sclerosis (SSc). METHODS: Antifibrillarin antibodies were determined by indirect immunofluorescence, immunoblotting, and immunoprecipitation, and HLA class II alleles by DNA oligotyping, in a large cohort of SSc patients. RESULTS: Antifibrillarin was found in 8% of 335 SSc sera and was significantly more common in blacks (16%) than whites (5%), in males (33%) than females (14%), and in patients with cardiac, renal, or gut involvement. The HLA class II haplotype DRB1*1302, DQB1*0604 was found significantly more frequently in SSc patients with antifibrillarin compared with race-matched normal controls and 260 SSc patients without antifibrillarin. In addition, 1 or more of the HLA-DQB1 alleles *0604, *0301, *0602, and/or *0302 was found in all antifibrillarin-positive patients, and 62% of the antifibrillarin-positive patients had 2 of these HLA-DQB1 alleles, a highly significant difference from both race-matched normal controls and antifibrillarin-negative SSc patients. CONCLUSION: Antifibrillarin, although an infrequent nucleolar autoantibody, is a marker for severe SSc, especially in blacks and males, and is strongly associated with a unique HLA haplotype, as well as with combinations of certain HLA-DQB1 alleles.

Alleles↗
PubMed1996

Ribosomal P autoantibodies in systemic lupus erythematosus. Frequencies in different ethnic groups and clinical and immunogenetic associations.

OBJECTIVE: To determine the frequencies and clinical associations of antiribosomal P antibodies (anti-P) in a large multiethnic cohort of patients with systemic lupus erythematosus (SLE), and to assess whether anti-P was associated with any major histocompatibility complex (MHC) class II alleles or shared amino acid sequences. METHODS: Sera from 394 SLE patients were studied for anti-P using an enzyme-linked immunosorbent assay, and MHC class II alleles (HLA-DRB1, DQA1, and DQB1) were determined by DNA oligotyping. RESULTS: Anti-P antibodies were found in 13-20% of patients in the majority of ethnic groups, but were perhaps more frequent in Chinese patients (36%) and less common in Bulgarian patients (6%). Neuropsychiatric lupus (psychosis and/or depression) was significantly associated with anti-P. The HLA-DR2, DQ6 haplotypes DRB1*1501 or *1503, DQA1*0102, and DQB1*0602 were increased in anti-P-positive whites, blacks, and Mexican Americans. The HLA-DQB1*0602 allele showed the strongest association with anti-P when these 3 ethnic groups were combined and compared with both race-matched anti-P-negative SLE patients and normal controls. The HLA-DQ8 specificity (DQB1*0302) was increased both in whites and in Mexican-Americans with anti-P who were negative for HLA-DQB1*0602, and perhaps also increased in Greeks, but not in blacks, in whom HLA-DQB1*0301 was increased. A shared amino acid sequence in HLA-DQB1 (at position 26 of leucine and position 30 of tyrosine) was strongly associated with anti-P positivity (70%) versus anti-P negativity (42%) across ethnic lines. CONCLUSION: The anti-P response in SLE patients, occurring in approximately 15% of patients, was strongly influenced by certain MHC class II alleles and was correlated with diffuse neuropsychiatric dysfunction.

Black or African American↗
PubMed2006

Immunogenetic risk and protective factors for juvenile dermatomyositis in Caucasians.

OBJECTIVE: To define the relative importance (RI) of class II major histocompatibility complex (MHC) alleles and peptide binding motifs as risk or protective factors for juvenile dermatomyositis (DM), and to compare these with HLA associations in adult DM. METHODS: DRB1 and DQA1 typing was performed in 142 Caucasian patients with juvenile DM, and the results were compared with HLA typing data from 193 patients with adult DM and 797 race-matched controls. Random Forests classification and multiple logistic regression were used to assess the RI of the HLA associations. RESULTS: The HLA-DRB1*0301 allele was a primary risk factor (odds ratio [OR] 3.9), while DQA1*0301 (OR 2.8), DQA1*0501 (OR 2.1), and homozygosity for DQA1*0501 (OR 3.2) were additional risk factors for juvenile DM. These risk factors were not present in patients with adult DM without defined autoantibodies. DQA1 alleles *0201 (OR 0.37), *0101 (OR 0.38), and *0102 (OR 0.51) were identified as novel protective factors for juvenile DM, the latter 2 also being protective factors in adult DM. The peptide binding motif DRB1 (9)EYSTS(13) was a risk factor, and DQA1 motifs F(25), S(26), and (45)(V/A)W(R/K)(47) were protective. Random Forests classification analysis revealed that among the identified risk factors for juvenile DM, DRB1*0301 had a higher RI (100%) than DQA1*0301 (RI 57%), DQA1*0501 (RI 42%), or the peptide binding motifs. In a logistic regression model, DRB1*0301 and DQA1*0201 were the strongest risk and protective factors, respectively, for juvenile DM. CONCLUSION: DRB1*0301 is ranked higher in RI than DQA1*0501 as a risk factor for juvenile DM. DQA1*0301 is a newly identified HLA risk factor for juvenile DM, while 3 of the DQA1 alleles studied are newly identified protective factors for juvenile DM.

Adolescent↗
PubMed1983

Simultaneous absence of the human IgG1, IgG2, IgG4 and IgA1 subclasses: immunological and immunogenetical considerations.

Simultaneous absence of the IgG1, IgG2, IgG4 and IgA1 immunoglobulins has been unambiguously demonstrated in a healthy 75-year-old woman by testing for allotypes, isoallotypes and for isotypes of these four subclasses. Only IgM, IgD, IgG3, IgA2 and IgE were present. The IgG3 levels were significantly increased. Family investigation showed inheritance of a haplotype Gm-;-;b A2m2. This person is homozygous for an extensive DNA deletion including the C gamma 1, C gamma 2, C gamma 4 and C alpha 1 genes.

Aged↗
PubMed2001

Immunogenetic analysis reveals that epitope shifting occurs during B-cell affinity maturation in primary biliary cirrhosis.

Primary biliary cirrhosis (PBC) is a liver disease characterized by serum autoantibodies against the pyruvate dehydrogenase complex (PDC) located in the inner mitochondrial membrane. The predominant target in PDC has previously been localized to the inner lipoyl domain (ILD) of the E2 subunit. The etiology of PBC is unknown, although molecular mimicry with bacterial PDC has been proposed. Here, we have investigated the etiology of PBC and nature of the autoimmune response by analyzing the structure of a human monoclonal antibody with ILD specificity. Mutants of the monoclonal antibody, which was originally isolated from a patient with PBC, were expressed as Fab by phage display, and tested for reactivity against recombinant domains of the E2 subunit. Fab in which the V(H)-encoded portions were reverted to germline lost reactivity against the ILD alone, but recognized a different epitope in a didomain construct encompassing the ILD, hinge region and E1/E3 binding domain. The complete V(H) and V(L )germline revertant was unreactive with the human ILD and didomain, the Escherichia coli didomain, and whole PDC. We hypothesize that the IgM on the surface of the naïve B-cell first recognizes an as yet unidentified antigen, and that accumulation of somatic mutations results in an intermolecular epitope shift directed towards an epitope involving the E1/E3 binding domain. Further mutations result in the specificity being redirected to the ILD. These findings also suggest that bacterial molecular mimicry is not involved in initiating disease.

Amino Acid Sequence↗
PubMed1994

Immunogenetic aspects of IgE-mediated responses.

The reported significant HLA association is consistent with the codominant expression of MHC-linked Ir genes. Similar studies are needed in the case of the other HLA-immune response associations. It seems unlikely that any unique HLA-D genetic sequence will be found only among subjects responding to a particular Ag. It is likely, however, that we will find that a particular sequence is a necessary, but not sufficient, requirement for responsiveness to a particular antigenic epitope. Previous family studies, in which failed to observed parent-to-child transmission of specific immune responsiveness to a particular allergen, suggest that further genetic and/or environmental factors are required for the expression of specific immune responsiveness. These factors include variations in the degree of antigenic exposure. Of particular importance is the need for Ag-specific TcR genes to be expressed in the mature T-cell repertoire. In study of the specific immune response, there have been several studies of the protein and DNA sequences of allergenic proteins; therefore, in regard to understanding the genetics of specific immune responsiveness to allergens and its relationship to atopic diseases, rapid advances can be anticipated over the next several years.

Allergens↗
PubMed1984

Cultured human T lymphocyte lines and clones as immunogenetic tools.

Human T lymphocytes were sensitized in vitro to allogeneic determinants encoded by the HLA region and subsequently cloned by limiting dilution in the presence of human T cell growth factor. An in vitro priming protocol entailing multiple rounds of allostimulation in mixed lymphocyte culture, using a disparate stimulating to responding cell ratio (10:1), enabled a high frequency of functionally active clones to be isolated. The specificity of the proliferative and cytotoxic reactivities was ascertained directly by screening in an HLA characterized family.

Alleles↗