The correlation between human leukocyte antigen-DRB1 alleles and anti-neutrophil cytoplasmatic antibodies in Han and Uygur ulcerative colitis patients in Xinjiang region

Abstract

Objective To study the correlation between human leukocyte antigen (HLA)-DRB1 alleles and anti neutrophil cytoplasmatic antibodies (ANCA) in Han and Uygur ulcerative colitis (UC)patients in Xinjiang region.Methods The serum ANCA was determined by indirect immunofluorescence assay in 62 Uygur UC patients,58 Han UC patients,188 Uygur and 184 Han healthy control individuals.HLA-DRB1 typing was performed by polymerase chain reaction-sequence based typing (PCR-SBT).The allele frequency of HLA-DRB1 was compared in ANCA positive and negative Han and Uygur patients as well as healthy controls.Stratified analysis was performed according to UC clinical type,severity and involvement.SPSS 17.0 software was applied for x2 test.Once P＜0.05,the odds ratio (OR) and 95％ confidence intervals (95％CI) was calculated.Results The positive rate of ANCA in Uygur UC patients (53.2％,33/62) was significantly higher than that of Han patients (34.5％,20/58) and the difference was statistically significant (x2=4.269,P =0.045).In Uygur,the gene frequency of HLA-DRB1 * 13 in ANCA positive UC patients (0.202)was significantly higher than that of ANCA negative patients (0.017) (x2 =10.092,P=0.016,OR=16.000,95％CI:2.892 to 88.524) and healthy controls (0.075) (x2=9.351,P＝0.040,OR=3.407,95％CI:1.666 to 6.971).The gene frequency of HLA-DRB1 * 13 in ANCA positive pancolitis type UC patients (9/15) was significantly higher than that of ANCA negative pancolitis type UC patients (1/14) and the difference was statistically significant (x2=8.955,P =0.040,OR =19.500,95％CI:2.787 to 136.461).However,in Han patients,there were no significant differences of HLA-DRB1 alleles frequencies among ANCA positive patients,ANCA negative patients and healthy controls (all P＞0.05),and the results of stratified analysis were same.Conclusions In Uygur UC patients of Xinjiang region,HLA-DRB1 * 13 may correlated with ANCA and with ANCA of pancolitis type UC patients.There is no such correlation in Han patients of Xinjiang region. Key words: Colitis, ulcerative; HLA-DRB1 chains; Antibodies, antineutrophil cytoplasmic; Ethnic groups