Disease predisposition of human leukocyte antigen class II genes influences the gut microbiota composition in patients with primary biliary cholangitis.

Background: The human leukocyte antigen (HLA) susceptibility gene is the main genetic risk factor for primary biliary cholangitis (PBC). The prognosis of patients with PBC is linked to gut microbiota dysbiosis. However, whether the HLA alleles are associated with the gut microbiota distribution and disease severity remains unknown. Methods: A cohort of 964 Chinese patients with PBC was enrolled at Beijing YouAn Hospital, Beijing, China. High-resolution genotyping of the HLA class I and class II loci from 151 of these patients was performed using sequence-based PCR. Stool samples were collected from 43 of the 151 fully HLA-typed patients to analyze their microbiota compositions via 16S RNA gene sequencing. Results: Of the 964 patients, the male:female ratio was 114:850, and 342 of these patients (35.5%) had already developed liver cirrhosis (LC) before enrollment. Patients with PBC showed a significantly higher frequency of HLA DRB1*08:03 than did the controls (21.2% vs. 9.0%, P=0.0001). HLA-DRB1*03:01, DRB1*07:01, DRB1*14:05, and DRB1*14:54 frequencies were also increased but did not reach significance after Bonferroni's correction. Conversely, the DQB1*03:01 frequency was significantly lower in patients with PBC than in the controls (24.5% vs. 39.2%, P=0.0010). The patients' gut microbiota were analyzed from four perspectives. The microbial community abundances were significantly lower in FHRAC-positive patients (patients with a combination of five HLA DRB1 high-risk alleles) than in FHRAC-negative patients (P<0.05). Of the top 10 microbial genera, Lachnospiraceae_incertae_sedis was higher in the FHRAC-positive patients than in the FHRAC-negative patients (P<0.05). linear discriminant analysis (LDA) effect-size (LEfSe) analysis showed different microbes at different levels in the FHRAC-negative patients but not in the FHRAC-positive patients. DQB1*03:01-positive patients contained mostly Lactobacillaceae at the family level. A comparison of the FHRAC-positive patients with and without liver cirrhosis showed that the abundances of Veillonella were significantly higher in patients with cirrhosis and FHRAC than in those without cirrhosis and are FHRAC-negative. Conclusion: The HLA class II genes may influence the gut microbiota compositions in patients with PBC. Differential gut microbiota were expressed at different taxonomic levels. Some bacterial abundances may be increased in FHRAC-positive patients with PBC and cirrhosis.

Clinical characteristics and HLA genotypes in Chinese patients with anti-SLA/LP-positive autoimmune hepatitis.

BACKGROUND: Anti-soluble liver antigen/liver pancreas (anti-SLA/LP) is a highly specific serological marker for the diagnosis of autoimmune hepatitis (AIH). The aim of the present study was to define the clinical characteristics and human leucocyte antigen (HLA) genotypes of Chinese patients with anti-SLA/LP positive AIH. METHODS: Ninety-one AIH patients who were anti-SLA/LP positive were enrolled in this case control study. Clinical information was obtained through reviewing patients' clinical notes. High-resolution genotyping of HLA-A, B, C, DRB1, and DQB1 alleles was performed by sequence-based typing polymerase chain reaction on 62 of the 91 patients. Data from 500 healthy patients were used as baseline controls. RESULTS: Anti-SLA/LP-positive AIH patients were characterized as follows: adults (age 20-80 years), female (88%), and frequent anti-nuclear antibody positivity (91%). Genetically, compared with the controls, HLA-B*35:01 and C*08:01 were significantly more frequent in patients. The frequencies of HLA-B*08:01, B*40:02, DRB1*04:01, DRB1*04:05, DRB1*14:01, and DRB1*16:02 increased, and the frequency in DRB1*15:01 decreased in patients, but did not reach significance after Bonferroni's correction. Patients with other autoimmune diseases had a higher DRB1*04:05 and DQB1*04:01 allele carrier frequency than those without. DRB1*04:05 and DQB1*04:01 alleles were found at increased frequency in patients with decompensated liver disease than those with compensated liver disease. CONCLUSIONS: Chinese anti-SLA/LP-positive AIH patients have some distinct clinical characteristics than other populations reported in the literature. The presence of certain specific HLA alleles could potentially increase the risk of developing anti-SLA/LP-positive AIH or other autoimmune disease and decompensated liver disease in the Chinese population.

Human leucocyte antigen alleles and haplotypes and their associations with antinuclear antibodies features in Chinese patients with primary biliary cirrhosis.

BACKGROUND & AIMS: Primary biliary cirrhosis (PBC) is an autoimmune liver disease. Genetic factors are critical in determining susceptibility to PBC. Among human leuocyte antigen (HLA) genes, an association between the DRB1*08 allele and PBC has been reported in many populations, but not in Chinese patients. METHODS: We investigated HLA-A, B, DRB1, and DQB1 alleles and haplotypes in 145 PBC patients and 500 healthy subjects. Patients were also stratified according to autoantibody features, and associations between these and HLA alleles were analyzed. RESULTS: Significant associations existed between HLA-DRB1*08:03 (22.1% vs. 9.0%, Pc < 0.0001, OR = 2.86), DQ2 (41.4% vs. 25.4%, Pc < 0.0001, OR = 2.07) and DQB1*06:01 (31.0% vs. 17.8%, Pc = 0.014, OR = 2.08) alleles and PBC. DRB1*08:03-DQB1*06:01 (22.1% vs. 8.2%, P < 0.0001, OR = 3.17) and DRB1*07:01-DQB1*02:02 haplotypes (28.3% vs. 17.6%, P = 0.005, OR = 1.85) were also associated with PBC susceptibility. In contrast, the DQB1*03:01 allele (21.4% vs. 39.2%, Pc < 0.0001, OR = 0.42) and DRB1*12:02-DQB1*03:01 haplotype (6.9% vs. 14.6%, P = 0.015, OR = 0.43) were significantly decreased in PBC patients compared with controls. DRB1*14:54 and DQ5(1) protected against antinuclear antibody (ANA) (OR = 0.25) and anti-gp210 antibody (OR = 0.39) production, respectively, while HLA-B*44:03 predisposed patients to anti-gp210 antibody (OR = 5.70) production. CONCLUSION: These results suggest that Chinese patients with PBC have a distinct genetic background in eastern Asia, and we confirmed the role of HLA genes in determining PBC susceptibility and autoantibody features in the Chinese population.