Chronic Viral Illness Service, McGill University Health Centre, 3650 Saint Urbain, Montreal, QC, Canada H2X 2P4 ; Research Institute, McGill University Health Centre, Montreal, QC, Canada H3H 2R9.
Chronic Viral Illness Service, McGill University Health Centre, 3650 Saint Urbain, Montreal, QC, Canada H2X 2P4 ; Research Institute, McGill University Health Centre, Montreal, QC, Canada H3H 2R9 ; Division of Hematology, McGill University Health Centre, 687 Pine Avenue West, Montreal, QC, Canada H3A 1A1.
J Immunol Res. 2015;2015:614127. doi: 10.1155/2015/614127. Epub 2015 Feb 22.
The gut microbiota plays a key role in health and immune system education and surveillance. The delicate balance between microbial growth and containment is controlled by the immune system. However, this balance is disrupted in cases of chronic viral infections such as HIV. This virus is capable of drastically altering the immune system and gastrointestinal environment leading to significant changes to the gut microbiota and mucosal permeability resulting in microbial translocation from the gut into the peripheral blood. The changes made locally in the gut have far-reaching consequences on the other organs of the body starting in the liver, where microbes and their products are normally filtered out, and extending to the blood and even brain. Microbial translocation and their downstream effects such as increased indolamine 2,3-dioxygenase (IDO) enzyme expression and activity create a self-sustaining feedback loop which enhances HIV disease progression and constitute a vicious cycle of inflammation and immune activation combining viral and bacterial factors. Understanding this self-perpetuating cycle could be a key element in developing new therapies aimed at the gut microbiota and its fallout after infection.
肠道微生物群在健康和免疫系统的教育和监测中起着关键作用。微生物生长和控制之间的微妙平衡由免疫系统控制。然而，在慢性病毒感染（如 HIV）的情况下，这种平衡会被打破。这种病毒能够极大地改变免疫系统和胃肠道环境，导致肠道微生物群和黏膜通透性发生显著变化，从而导致微生物从肠道转移到外周血液中。肠道内的局部变化对身体的其他器官产生深远的影响，从肝脏开始，微生物及其产物通常在肝脏中被过滤掉，然后延伸到血液，甚至大脑。微生物易位及其下游效应，如增加吲哚胺 2,3-双加氧酶（IDO）酶的表达和活性，形成一个自我维持的反馈环，增强 HIV 疾病的进展，并构成炎症和免疫激活的恶性循环，结合病毒和细菌因素。了解这种自我维持的循环可能是开发针对感染后肠道微生物群及其后果的新疗法的关键因素。
