HLA-DRB1*01 and DRB1*04 alleles in Sardinian rheumatoid arthritis patients

In Sardinia, like in other Caucasoid populations, rheumatoid arthritis (RA) is significantly associated with HLA-DR4 and DR1 antigens. To discover which DR4 and DR1 alleles were associated with the disease we selected 22 Sardinian patients affected by RA. Fifty DR4+ and 28 DR1+ healthy individuals coming from the same geographical area were used as controls. In the Sardinian patients only two DRB1*04 alleles were observed: DRB1*0405 in 11 and DRB1*0403 in three patients. The DRB1*0102 allele was observed in two patients and DRB1*0101 in six patients. Hereditary predisposition to RA in Sardinia therefore seems to be almost exclusively associated with the DRB1*0405 and DRB1*0101 alleles which share the 67LLEQRRAA74-85VG86 epitope in the peptide binding groove.     

Endothelial dysfunction in rheumatoid arthritis: influence of HLA-DRB1 alleles

Cardiovascular disease is the commonest cause of premature mortality in rheumatoid arthritis (RA) patients. Vascular endothelial injury is the primary event in atherosclerosis. It has been associated with endothelial dysfunction. We have recently observed that actively treated RA patients had endothelial dysfunction. HLA-DRB1 shared epitope alleles, in particular HLA-DRB1*0404, seem to be implicated in the development of endothelial dysfunction. These results underline the influence of genetic factors in the risk of atherosclerosis in RA patients.     

HLA-DRB1 alleles and HLA-DRB1 shared epitopes are markers for juvenile rheumatoid arthritis subgroups in Colombian mestizos

We studied the association of human leukocyte antigen (HLA)-DRB1 and HLA-DQB1 alleles and HLA haplotypes with juvenile rheumatoid arthritis (JRA) in 65 patients and 65 controls from Colombia. The JRA subsets were distinguished on the basis of criteria established by the American College of Rheumatology. Two alleles were associated with protection, HLA-DRB1*1501 (p = 0.002) and HLA-DRB1*1402 (p = 0.01). HLA-DRB1*1602 (p = 0.0000002) was associated with susceptibility for systemic JRA and HLA-DRB1*1104 (p = 0.0002) for pauciarticular JRA. Amino acid sequences at residues 70-74 of DRB1 chain shared by HLA-DRB1 alleles (shared epitomes) were also informative. The polyarticular JRA subset revealed association with (70)QRRAA(74), which includes HLA-DRB1*04, 01, and (70)DRRAA(74), which includes DRB1*1601, 1602, 1101, and 1104. Two new findings of interest were the association of the haplotypes DRB1*1104, DQB1*0301(p = 0.0002) with pauciarticular JRA and DRB1*1602, DQB1*0301 (p = 0.0000002) association with systemic JRA. The DRB1 alleles of these two haplotypes share the epitope (70)DRRAA(74)and were associated with both the pauciarticular and the systemic subset of JRA. Our results suggest that studies of disease susceptibility in populations of admixed genetic background should take into account the contribution of different ethnic groups or nationalities in the recruitment of controls and patients studied in order to rule out genetic stratification.     

Functional categorization of HLA-DRB1 alleles in rheumatoid arthritis: the protective effect

Because of past recombination event, human leukocyte antigen (HLA) alleles that are not closely related in overall sequence may come to resemble each other in areas coding for peptide binding regions (PBR) of HLA molecules. Peptide binding is likely to be important for the role of HLA molecules in autoimmune disease. As a result, it has been suggested that a strategy of searching for HLA disease associations that groups alleles in functional categories based on PBR motifs may be more successful than conventional strategies based on studying different alleles. Using such functional categorization, we examined the possibility of discriminating subcategories of HLA-DRB1 alleles associated with rheumatoid arthritis (RA) in a Southern French population. HLA-DRB1 genotyping was performed by polymerase chain reaction with sequence-specific oligonucleotide hybridization or sequence-specific primers. HLA-DRB1 alleles were classified according to a functional categorization that defined seven similar subregion structures or restrictive supertype patterns (RSPs) within pocket 4 of HLA-DR peptide binding groove as the molecular basis for grouping these alleles. HLA-DRB1* RSPs "A," "De," "Q," "Dr," "E," " R," and "a" association with susceptibility or resistance to disease was then studied in 200 RA patients versus 200 controls. DRB1* RSP "A" containing the shared epitope alleles (DRB1*0101, *0102, *0401, *0404, *0405, *0408, *1001, *1402; odds ratio [OR] = 4.35; pc < 0.001) had a predisposing effect, with double-dose effect as expected, OR 6.68 (pc < 0.001). Among the six remaining RSPs, two had significantly protective effect: DRB1* RSP "De" (DRB1*0103, *0402, *1102, *1103, *1301, *1302, *1304; OR = 0.33; p(c) < 0.001), and DRB1* RSP "Q" (DRB1*0701; OR = 0.40; pc < 0.001). One had non-significantly protective effect: DRB1* RSP "Dr" (DRB1*08, *1101, *1104, *1106, *12, *1303, *16; OR = 0.68; p < 0.05, pc = not significant [NS]). Three had neutral effect: HLA-DRB1* RSPs "E" (DRB1*0403, *0407, *0901, *1401; OR = 0.71; p = NS), " R" (DRB1*0301, *0302; OR = 0.76; p = NS), and "a" (DRB1*1501, *1502; OR = 0.94; p = NS). The functional categorization allowed us to discriminate among the HLA-DRB1 alleles those that confer a predisposing effect, a neutral effect, and a protective effect in RA.     

HLA-DRB1*04 alleles in psoriatic arthritis: comparison with rheumatoid arthritis and healthy controls.

Psoriatic arthritis (PsA) is an inflammatory arthritis associated with psoriasis usually seronegative for rheumatoid factor. An increased frequency of HLA-DR4 has been noted in PsA, particularly among patients with a rheumatoid arthritis like (RA) arthritis. The aim of the current investigation was to compare HLA-DRB1*04 alleles in patients with PsA, patients with RA, and healthy controls. Sample size calculations based on the frequency of HLA-DR4 suggested that 90 individuals in each patient group would be sufficient to address our question. Therefore, 90 HLA-DRB1*04 positive patients from each patient group underwent high resolution molecular typing and were included in this study. Although HLA-DRB1*0401 was the most frequent allele in all groups, its frequency among the PsA patients was lower than that of RA patients and controls. HLA-DRB1*0402 was higher among patients with PsA. Patients with RA were more likely to have more than one shared epitope allele than either PsA or the healthy control group. HLA-DQB1 alleles did not contribute further information. We suggest that the differences in the class II HLA epitope(s) may also be related to interaction specificity with another molecule functioning in the immune response to a putative arthritogenic antigen and result in differences in disease expression.     

中国人类风湿关节炎与PAD14功能基因多态性及部分HLA-DRB1等位基因相关性研究

目的 分析类风湿关节炎(rheumatoid arthritis,RA)中4型肽精氨酸转亚胺基酶(peptidylarginine deiminase IV,PAD14)功能基因多态性,探讨PAD14基因多态性与RA易感性的关系,以及编码与RA易感性相关HLA共同表位(shared epitope,SE)的HLA-DRB1等位基因与PAD14基因多态性的相关性.方法 采用逆转录合成cDNA、DNA测序和T载体克隆方法 分析67例RA患者、81名正常人PAD14基因外显子4个单核苷酸多态性(single nucleotide polymorphisms,SNPs),包括PADH_89*A/G,PADl4 90*C/T,PAD1492*C/G,PAD14 104*C/T;采用PCR-序列特异性引物方法 分析HLA-DRB1.*-01、*04、* 10基因型.结果 RA患者PAD14 89、90、104位基因多态性分布与正常对照组比差异有统计学意义,携带PAD14少见等位基因者对RA的危险性较携带常见等位基因者显著增加;分析编码SE等位基因与PAD14 SNPs的相关性发现,SE+/PAD14_89G-携带者较SE-/PAD14_89G-携带者发生RA的危险性高4.7倍(OR=4.7,95%CI:1.6～13.4,P=0.003),携带SE+/PAD14 89G+者高5.6倍(OR=5.6,95%CI:2.0～15.7,P=0.003).在PAD14 90、92、104位均出现相似的情况.结论 PAD14功能基因多态性与中国人RA的易感性相关,编码SE的HLA-DRB1等位基因仍然是RA的重要遗传标记,而且HLA-DRB1等位基因与PAD14的少见等位基因间可能存在一定的协同作用.     

Epigenome-wide methylation haplotype association analysis identified HLA-DRB1, HLA-DRB5 and HLA-DQB1 as risk factors for rheumatoid arthritis

The aim of this study was to compare nonrandom associations between physically adjacent single methylation polymorphism loci among rheumatoid arthritis (RA) and normal subjects for investigating RA-risk methylation haplotypes (meplotype). With 354 ACPA-positive RA patients and 335 normal controls selected from a case–control study based on Swedish population, we conducted the first RA epigenome-wide meplotype association study using our software EWAS2.0, mainly including (i) converted the β value to methylation genotype (menotype) data, (ii) identified methylation disequilibrium (MD) block, (iii) calculated frequent of each meplotypes in MD block and performed case–control association test and (iv) screened for RA-risk meplotypes by odd ratio (OR) and p-values. Ultimately, 545 meplotypes on 334 MD blocks were identified significantly associated with RA (p-value < .05). These meplotypes were mapped to 329 candidate genes related to RA. Subsequently, combined with gene optimization, eight RA-risk meplotypes were identified on three risk genes: HLA-DRB1, HLA-DRB5 and HLA-DQB1. Our results reported the relationship between DNA methylation pattern on HLA-DQB1 and the risk of RA for the first time, demonstrating the co-demethylation of ‘cg22984282’ and ‘cg13423887’ on HLA-DQB1 gene (meplotype UU, p-value = 2.90E − 6, OR = 1.68, 95% CI = [1.35, 2.10]) may increase the risk of RA. Our results demonstrates the potential of methylation haplotype analysis to identify RA-related genes from a new perspective and its applicability to the study of other disease.     

Meta-analysis of HLA-DRB1 polymorphism in Latin American patients with rheumatoid arthritis

OBJECTIVES: To estimate the common effect size of HLA-DRB1 alleles on rheumatoid arthritis (RA) susceptibility across Latin America populations through a meta-analysis combining the results of published data. METHODS: Case-control studies on HLA-DRB1 association with RA in Latin America were searched up to October 2006. Genotype frequencies were extracted according to both shared epitope (SE) and HLA-DR4 positive or negative alleles. The effect summary odds ratio (OR) and 95% confidence intervals was obtained. Heterogeneity and publication bias were assessed. RESULTS: Eight studies containing 684 cases and 1015 controls were included. Under the random effects model, the common OR was 3.28 (1.93, 5.60) (p<0.0001) and 3.54 (2.47, 5.05) (p=4.22 x 10(-12)) for HLA-DR4 and SE, respectively. There was no evidence of publication bias according to Funnel plot and Egger's regression test (p=0,445 for DR4 and p=0,464 for SE meta-analysis). Significant heterogeneity was observed for HLA-DR4 (I2=81.06%, Q=36.96, p=0.000005) but not for the SE meta-analysis. CONCLUSIONS: HLA-DR4 and SE positive HLA-DRB1 alleles (mainly HLA-DRB10404) are associated with RA in Latin Americans. Heterogeneity is expected owing to the diverse degree of admixture between the examined populations. Our findings support the HLA as a major susceptibility locus for RA and validate the SE hypothesis in Latin America.     

Associations of HLA-DRB1 and -DQB1 alleles with severe recurrent respiratory papillomatosis in Korean patients

Recurrent respiratory papillomatosis (RRP) is characterized by frequent recurrences of papilloma of the larynx with significant morbidity. It is caused by human papillomavirus (HPV) types 6 and 11. Some associations of HLA genes with RRP have been reported, mainly in Caucasians. We performed HLA class II (DRB1 and DQB1) genotyping using Dynal RELI™ HLA-DRB1 SSO kit and PCR-single strand conformation polymorphism on 22 Korean patients with severe RRP and 207 healthy controls. The gene frequencies of HLA-DRB1*11:01 (18.2% vs 3.6%, p = 0.0006, p_c = 0.02, odds ratio [OR] = 5.9) and DQB1*03:01 (36.4% vs 14.5%, p = 0.0009, p_c = 0.01, OR = 3.4) and the haplotype frequency of DRB1*11:01-DQB1*03:01 (15.9% vs 3.6%, p = 0.003, OR = 5.0) was higher in RRP patients than controls. DRB1*11:01 and DRB1*11:01-DQB1*03:01 haplotype were strongly associated with disease susceptibility to severe RRP in Koreans.     

HLA-DRB1 motifs and heat shock proteins in rheumatoid arthritis

Susceptibility to develop Rheumatoid arthritis (RA) maps to a highly conserved amino acid motif expressed in the third hypervariable region of different HLA-DRB1 alleles. This motif, namely QKRAA, QRRAA or RRRAA helps the development of RA by an unknown mechanism. In the past ten years, we have extensively studied the unique properties of the QKRAA motif of HLA-DRB1*0401 and have found: (1) That it can constitute B and T cell epitopes on many infectious agents; (2) That it can shape the T cell repertoire; (3) That it is overrepresented in protein databases; (4) That it constitutes a binding motif for the highly conserved family of 70 kD heat shock proteins. This may cause abnormal trafficking of HLA-DRB1*0401 in B cells and/or abnormal T cell responses to bacterial and human 70 kD heat shock proteins in people who express HLA-DRB1*0401.     

HLA-DRB1 and -DQB1 alleles in mestizo patients with Vogt-Koyanagi-Harada's disease in Southern California

We evaluated human leukocyte antigen (HLA)-DRB1 and -DQB1 alleles as genetic markers for Vogt-Koyanagi-Harada (VKH) disease in Mestizo patients in Southern California. Mestizo individuals with VKH disease (n = 29) at two institutions were evaluated. Typing of HLA-DRB1 and DQB1 genes was performed using DNA-based techniques. Gene frequencies were compared to Mestizo individuals living in Southern California. All patients had HLA-DRB1*01, DRB1*04, DQB1*03 or DQB1*05, or a combination of these genes. The gene frequency of combined HLA-DR4 alleles was increased when compared to controls. The frequencies of HLA-DRB1*0404 and DRB1*0407 were increased compared to controls, but were not significant after Bonferroni correction. Three patients had the HLA-DRB1*0410 allele; this allele was not found in controls. All HLA-DRB1*01 positive patients had the DRB1*0102 subtype. No HLA-DQB1 allele was significantly increased compared to controls. This study is the first to identify a possible association between HLA-DRB1*0404 and VKH disease, as well as to find DRB1*0102 and DRB1*0410 in Mestizo patients.     

HLA-DRB1 and anti-cyclic citrullinated peptide antibody production in rheumatoid arthritis

Anti-cyclic citrullinated peptide antibodies (anti-CCP) are a new diagnostic marker for rheumatoid arthritis (RA), which shows a specificity of 97% and a sensitivity of 81% in the second generation assay. About 61% of RA patients express HLA-DRB1*0401. In a cohort of patients with RA we investigated whether the expression of anti-CCP correlates with the carriage of certain genes on the HLA-DRB1 locus. Our data reveal a highly significant association between anti-CCP and HLA-DR4, and a weaker but still significant association with HLA-DR1. HLA-DRB1*0401 is not a prerequisite for anti-CCP production, but if HLA-DRB1*0401 was present, 90% of our RA patients were anti-CCP positive.     

HLA DPB1 alleles and susceptibility to rheumatoid arthritis.

HLA-DPB1 genotypic and phenotypic frequencies were investigated in a series of 35 adult rheumatoid arthritis (RA) patients and 42 controls. No significant associations between DPB1 alleles and susceptibility to RA were demonstrated, although some non-significant differences in DPB1*0301 and 0401 allele frequencies between patients and controls were observed.     

Contribution of LILRB1 polymorphism and HLA-DRB1-shared epitope to rheumatoid arthritis

Objectives

The LILRB1 gene has recently been associated with rheumatoid arthritis (RA) susceptibility in HLA-DRB1-shared epitope (SE) negative Japanese individuals. Since the contribution of the LILRB1 polymorphism to RA susceptibility may vary among ethnic populations, we examined this association in a group of Caucasian patients. The frequency of LILRB1 alleles was also determined in patients according to the presence of DRB1-SE.

Methods

Samples from 103 RA patients and 107 healthy controls were randomly collected. Polymorphism of the LILRB1 gene was analyzed by sequencing with primers that amplified intron 3 and exon 4.

Results

The frequencies of LILRB1 alleles in RA patients did not differ from those of controls. However, when patients and controls were grouped according to SE, the PE-01/01 genotype was less frequent in negative-SE patients than in controls. Whereas SE is associated with higher anti-CCP antibody levels, as expected, the production of anti-CCP antibodies was lower in negative-SE patients with PE-01/01 genotype. Moreover, radiographic damage in hand and feet of SE-negative PE-01/01 patients was less severe than in patients with other genotypes.

Conclusions

The participation of this LILRB1 polymorphism in the RA pathogenesis of this Caucasian cohort differed from that reported in a Japanese sample. Our findings suggest that the LILRB1-PE-01/01 genotype could exert a protective role in RA susceptibility and disease severity in the absence of SE.     

The role of HLA-DRB1 alleles on susceptibility of Chinese patients with anti-GBM disease

Anti-glomerular basement membrane (GBM) disease, a rare autoimmune disorder, is associated with HLA-DR15 genotype in Caucasian and Japanese populations. But the distribution of HLA-DRB1 alleles in Chinese patients with anti-GBM disease and their association with clinical characteristics of anti-GBM disease are to be determined. The present study analyzed the HLA-DRB1 alleles by sequence based typing in 44 Chinese patients with anti-GBM disease and 200 healthy controls. The effects of DRB1 alleles on susceptibility to anti-GBM disease were examined by a relative predispositional effects (RPEs) method. The clinical and pathological data of the patients were collected and analyzed. The DRB11501 allele was significantly associated with anti-GBM disease (p = 1.597 × 10⁻⁷). The RPEs test also showed a significant increased frequency of DRB10404 in anti-GBM disease (p = 0.037). Interestingly, the patients with DRB11501 or 0404 had more crescent formation in glomeruli than those without the two alleles (p = 0.021). But the DRB10404 was rare in both patients and control groups, which indicates that the importance of the 0404 allele is limited in anti-GBM disease. We conclude that the HLA-DRB11501 allele is a genetic marker for susceptibility to anti-GBM disease.     

HLA-DRB1, -DQB1 alleles in head and neck carcinoma patients

Certain HLA class II alleles have been reported to play a role in development or prevention of cervical carcinoma, an epithelial malignancy linked to human papillomavirus (HPV). In head and neck carcinomas, of which a subset is also HPV associated, the impact of HLA genes remains unknown. HLA-DRB1, -DQB1 alleles were determined in a comprehensive series of 162 head and neck carcinoma patients, for which 83 consecutive cadaveric organ donors of Finnish origin served as controls. DRB1*03 was associated with node-negative disease and DRB1*08 and 13 with small tumors; DRB1*04 was protective against disease relapse. Most alleles of borderline significance in this study act similarly in cervical carcinomas.     

HLA-DRB1 alleles and juvenile idiopathic arthritis: Diagnostic clues emerging from a meta-analysis

Juvenile Idiopathic Arthritis (JIA) is characterized with a variable pattern of articular involvement and systemic symptoms and, thus, it has been classified in several subtypes. Genetic predisposition to JIA is mainly due to HLA class II molecules (HLA-DRB1, HLA-DPB1), although HLA class I molecules and non-HLA genes have been implicated, too. Here, we carried out a meta-analysis including selected studies designed to assess HLA genetic background of JIA patients, compared to healthy controls; particularly, we focused our attention on HLA-DRB1. In summary, our meta-analysis showed four main findings regarding HLA-DRB1 locus as a genetic factor of JIA: i) HLA-DRB1*08 is a strong factor predisposing to JIA, both for oligo-articular and poly-articular forms (oJIA > pJIA); ii) HLA-DRB1*01 and HLA-DRB1*04 may be involved in the genetic predisposition of Rheumatoid Factor (RF) positive forms of JIA; iii) HLA-DRB1*11 was confirmed to be predisposing to oligo-articular JIA; iv) HLA-DRB1*04 was confirmed to have a role in systemic JIA. Importantly, RF positivity seems to select the JIA clinical subset with the strongest immunogenetic similarities with adult rheumatoid arthritis.     

Ten novel HLA-DRB1 alleles and one novel DRB3 allele

Ten novel HLA-DRB1 and one DRB3 alleles are described. Eight of the variants are single-nucleotide substitutions, four resulting in an amino acid change (DRB1*1145, *1148, *0828 and *1514) and four with silent substitutions (DRB1*040504, *130103, *160502 and DRB3*020204). Two alleles differ by two nucleotide changes altering one (DRB1*1447 and *1361) amino acid and one allele alters three nucleotides and two amino acids.     

Identification of HLA-DRB1 alleles associated with Graves' disease in Koreans by sequence-based typing

The human leukocyte antigen (HLA) region, particularly class II genes, plays a primary role in the susceptibility to development of GD. We investigated the allelic polymorphism of HLA class II DRB1 genes to examine its association with GD in Koreans. We performed the high resolution polymerase chain reaction-sequence based typing (PCR-SBT) of HLA-DRB1 in 133 patients with GD and 200 healthy controls. Compared to healthy controls, the patients with GD had increased frequencies of DRB1*030101 (4.9% vs.1.8%, p = 0.034), DRB1*080201 (5.3% vs. 2.3%, p = 0.050) and DRB1*140301 (3.4% vs. 1.0%, p = 0.043). In contrast, the frequencies of DRB1*070101 (3.0% vs. 7.3%, p = 0.024) and DRB1*130201 (4.1% vs. 9.0%, p = 0.010) were decreased in the patients with GD. However, the corrected p values were not significant in above all alleles. Patients with DRB1*040301 were significantly older than controls (45 years vs. 35 years, p = 0.017). DRB1*040301, DRB1*150201, DRB1*120101 and DRB1*120201 were associated with male predominance, strong familial associations, thyroid ophthalmopathy and radioactive iodine therapy, respectively. In conclusion, there were no significant HLA-DRB1 alleles associated with GD in Koreans, although some alleles were correlated with the clinical characteristics.