Objective To elucidate the causal relationship between specific immune cells and autoimmune hepatitis(AIH)using a two-sample Mendelian randomization(MR)approach.Methods A bidirectional MR analysis was conducted using data from large publicly accessible Genome-Wide Association Study(GWAS)databases.The inverse variance weighted(IVW)method was employed as the primary method to evaluate the relationship between 731 immune cell traits and AIH.The false discovery rate(FDR)was controlled using the Benjamini-Hochberg correction.Additionally,pleiotropy and heterogeneity tests were performed,and a leave-one-out sensitivity analysis was conducted to further validate the robustness of the results.Results At a significance level of 0.20,it was found that the absolute count of CD28-CD8+regulatory T-cells(IVW:odds ratio[OR]=1.486;95％confidence interval[CI],1.189-1.859;P＜0.001;PFDR=0.185),the level of CD28 on CD39+secreting regulatory T-cells(IVW:OR=1.194;95％CI,1.074-1.328;P=0.001;PFDR=0.185),and the level of CD45 on mononuclear myeloid-derived suppressor cells(IVW:OR=1.243;95％CI,1.108-1.394;P＜0.001;PFDR=0.143)were associated with an increased risk of AIH.The level of programmed death-ligand 1 on CD14+CD16+monocytes(IVW:OR=0.849;95％CI,0.771-0.935;P＜0.001;PFDR=0.185)was associated with a reduced risk of AIH.Conclusion Four immune cell phenotypes associated with AIH risk are identified.Further investigation is needed to validate these findings and explore new therapeutic avenues.

objective To investigate the epidemiological and molecular typing features of the pathogenic Haemophilus influenzae(H.influenzae)by biotyping,serotyping and pulsed-field gel electrophoresis(PFGE).Methods A total of 273 invasive isolates of H influenzae were collected from the pediatric patients with pneumonia at Chengdu Children Hospital of Sichuan province from 1988 and 2004 to 2007.The idenbfication of H.influenzae strains were done according to the laboratory standard methodology described by Manual of Clinical Microbiology(American).All strains were biotyped according to Kilian's classification with the API[R]NH system.And serotyped by a slide agglutination assay with type a to f specific antlaerum as described by Pittman.PCR method for identification of H.influenzae were performed as described by Falla.One hundred of 273 strains were analyzed by PFGE as described by Saito with some modifications.The resuIts of PFGE were analyzed by Bionumerics soft(Version 4.0,Applied Maths BVBA,Belium).Restilts 78.2%of 273 cases occurred under 1 years old.Eight biotypes were found among the 273 H.influenzae isolates.17.6%(48/273)of all isolates belonged to biotype Ⅰ,43.6%(119/273)were biotype Ⅱ,22.7%(62/273)were biotype Ⅲ,7.3%(20/273)were biotype Ⅳ,5.9%(16/273)were biotype Ⅴ,0.4%(1/273)were biotype Ⅵ,1.8%(5/273)were biotype Ⅶ and 0.7%(2/273)were biotype Ⅷ.respeetively.99.6% of all 273 isolates were nontypeable.There was only one isolate was serotvpe f Ninty-six PFGE genotypes were obtained in this study.One hundred strains demonstrated a variety of genomic Datterns by PFGE.The most isolates of the flame PFGE genotype(type 35)was 3 isolates.Each of93 PFGE genotypes was represented by only a single isolate.The genotypes distribution didn't correlate with the time distribution of the strains were isolated.Conclusion Nontypeable H.influenzae primarily caused acute Dneumoma in children under 1 years old.They mostly belonged to biotype Ⅰ,Ⅱ and Ⅲ biotypes.The nontypeable H.influenzae strains appeared to more heterogeneous patterns by PFGE genotyping.Genotyping may helP understand the molecular characteristics of outbreak and endemicity according to the results of PFGE.PFGE genotyping proved to have a much stronger discriminatory power than either serotyping or biotyping.Our findings suggest that PFGE analysis is useful for the epidemiologieal study of H.influenzae infections.