HIV-associated gut microbial alterations are dependent on host and geographic context. hiv_gut_microbe_host_geographic_context

HIV-associated changes in intestinal microbiota are believed to be important drivers of disease progression. However, the majority of studies have focused on populations in high-income countries rather than in developing regions where HIV burden is greatest. To better understand the impact of HIV on fecal microbiota globally, we compare the fecal microbial community of individuals in the U.S., Uganda, and Botswana. We identify significant bacterial taxa alterations with both treated and untreated HIV infection with a high degree of uniqueness in each cohort. HIV-associated taxa alterations are also significantly different between populations that report men who have sex with men (MSM) behavior and non-MSM populations. Additionally, while we find that HIV infection is consistently associated with higher soluble markers of immune activation, most specific bacterial taxa associated with these markers in each region are not shared and none are shared across all three geographic locations in our study. Our findings demonstrate that HIV-associated changes in fecal microbiota are overall distinct among geographical locations and sexual behavior groups, although a small number of taxa shared between pairs of geographic locations warrant further investigation, highlighting the importance of considering host context to fully assess the impact of the gut microbiome on human health and disease.

HIV感染相关的肠道菌群（intestinal microbiota）改变被认为是疾病进展的关键驱动因素。然而，绝大多数相关研究均聚焦于高收入国家人群，而非HIV负担最重的发展中地区人群。为全面阐明HIV对全球粪便菌群（fecal microbiota）的影响，本研究对比分析了美国、乌干达及博茨瓦纳三地人群的粪便微生物群落（fecal microbial community）组成。本研究发现，接受治疗与未接受治疗的HIV感染者均存在显著的细菌类群（bacterial taxa）改变，且各队列（cohort）的菌群特征均具有高度独特性。自述为男男性行为者（men who have sex with men, MSM）的人群与非MSM人群之间，HIV相关的细菌类群改变同样存在显著差异。此外，尽管本研究发现HIV感染始终与更高水平的免疫激活可溶性标志物（soluble markers of immune activation）相关，但各地区与这些标志物相关的特异性细菌类群大多并不重合，且本研究中三个地理区域均共有的类群则完全不存在。本研究结果表明，HIV相关的粪便菌群改变在不同地理区域与性行为群体中整体存在显著差异；尽管部分成对地理区域间存在少量共有的细菌类群，值得进一步研究，但这一结果也凸显了考量宿主背景的重要性——唯有如此才能全面评估肠道微生物组（gut microbiome）对人类健康与疾病的影响。