Characterization Of The Gut Microbiota In Immunological Non-Responders Among HIV Infection

Objective:Acquired immunodeficiency disease syndrome(AIDS)has become a major threat to human health and past research has shown that the structure and function of the gut microbiota changes following human immunodeficiency virus(HIV)infection.Although active anti-retroviral therapy(ART)can improve the dysbiosis of the gut microbiota caused by HIV infection,it does not lead to complete recovery,and the immune response to ART varies between HIV-positive individuals,as does the degree of recovery of CD4~+T-lymphocyte counts.In contrast,the role of gut microbiota in HIV infection and immune response has not been clarified.In this study,the structure and composition of the gut microbiota of healthy controls(HC),immune responder(IR)and immune non-responder(INR)were analysed by 16S ribosomal DNA amplicon sequencing in order to:(1)Carify the differences in the structure and composition of the gut microbiota between HIV and HC;(2)Investigate the characteristics of the gut microbiota of IR and INR;and(3)Explore the relevance of differential microbiota associated with HIV infection to inflammatory factors and microbial translocation.Methods:The study consecutively included 68 HIV-infected patients attending the Infectious Diseases Hospital of Anhui Provincial Hospital,the First Affiliated Hospital of the University of Science and Technology of China,between December 2021 and March 2022,divided into 35 IR and 33 INR,and 15 men who have sex with men(MSM)from Public Health Service Centre and 12 friends and relatives of HIV-infected patients who accompanied the clinic as HIV-negative controls.A self-designed questionnaire was used to investigate the basic demographic information,dietary habits and lifestyle habits of the study subjects using a combination of electronic and paper questionnaires.Blood and stool samples were also collected from the study subjects,while clinical information on HIV-infected patients was collected from the outpatient antiretroviral treatment bank.The gut microbiota of the study population was examined by 16S r DNA amplicon sequencing,and the structure and composition of the different groups of microbiota and differences were analysed.Results:(1)There were 68 HIV and 27 HC among the study participants,with a median age of 39.00(31.00,51.00),89(93.68%)were male,and most had university degrees or higher(58.95%).(2)Alpha diversity of gut microbiota was higher in the HIV than in the HC,and Beta diversity showed that there were also structural differences between the two groups.The relative abundance of 25 species,including Acidaminococcus,Actinomyces,Collinsella,Fusobacterium,Megamonas,Megasphaera and Slackia,were found in elevated relative abundance in the HIV-infected group.(3)HIV-infected patients were divided into 35 in the IR group and 33 in the INR group based on current CD4~+T-lymphocyte counts combined with duration of ART and viral load;there were no statistical differences in demographic information and dietary habits between the two groups(all P>0.05).(4)The abundance of Porphyromonadaceae,Parabacteroides,Veillonella and Butyricimonas was elevated in the IR group,and Actinomycetales,Micrococcaceae,Actinomyces,Intestinibacter,Rothia Micrococcaceae,Actinomyces,Intestinibacter,and Rothia were more abundant in the INR group(all LDA>2.000,P<0.05).A random forest model screened five species of Clostridium spp.Xl Va(Clostridium＿Xl Va),Streptococcus,alloprevotella,Roseburia and Parabacteroides as diagnostic biomarkers of immune nonresponsiveness in HIV-infected patients.(5)TNF-αwas inversely correlated with the relative abundance of Dialister(r=-0.278,P=0.022);IL-6 was significantly negatively correlated with the relative abundance of Dialister,Actinomyces and Parabacteroides(Dialister:r=-0.457,P<0.001;Actinomyces:r=-0.251,P=0.039;Parabacteroides:r=-0.262,P=0.031).CD54 was also negatively correlated with Dialister(r=-0.306,P=0.011)and also with the relative abundance of Subdoligranulum(r=-0.265,P=0.029).The concentration of the microbial translocation marker LBP was negatively correlated with the relative abundance of Dialister(r=-0.290,P=0.016);the inflammatory marker CRP was also negatively correlated with the relative abundance of Dialister(r=-0.274,P=0.024)and with Sporobacter and Veillonella(Sporobacter:r=-0.264,P=0.030;Veillonella:r=-0.246,P=0.043).Both recent CD4~+T-lymphocyte counts and CD4~+T-lymphocyte counts at diagnosis were positively correlated with the relative abundance of Butyricimonas and Parabacteroides(all P<0.05),Rothia and Veillonella were negatively correlated with recent CD4~+T-lymphocyte counts(Rothia:r=-0.309,P=0.010;Veillonella:r=-0.247,P=0.043),Odoribacter spp.0.309,P=0.010;Veillonella:-0.247,P=0.043)and Odoribacter spp.were positively correlated with CD4~+T-lymphocyte counts at diagnosis(r=0.250,P=0.039).Conclusions:This study validated the changes in the structure and composition of the gut microbiota of HIV-infected patients.This study provides clues for the discovery of new methods of treatment for HIV infection and non-invasive diagnosis of immune non-response from the perspective of intestinal flora.