AUTHOR=Liu Jinbiao , Xiao Qianhao , Zhou Runhong , Wang Yong , Xian Qiaoyang , Ma Tongcui , Zhuang Ke , Zhou Li , Guo Deyin , Wang Xu , Ho Wen-Zhe , Li Jieliang TITLE=Comparative Analysis of Immune Activation Markers of CD8+ T Cells in Lymph Nodes of Different Origins in SIV-Infected Chinese Rhesus Macaques JOURNAL=Frontiers in Immunology VOLUME=7 YEAR=2016 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2016.00371 DOI=10.3389/fimmu.2016.00371 ISSN=1664-3224 ABSTRACT=

Altered T-cell homeostasis, such as expansion of CD8+ T cells to the secondary lymphatic compartments, has been suggested as a mechanism of HIV/simian immunodeficiency virus (SIV)-pathogenesis. However, the role of immune activation of CD8+ T cells in the CD4/CD8 turnover and viral replication in these tissues is not completely understood. In this study, we compared the expression of immune activation markers (CD69 and HLA-DR) on CD8+ T cells in the peripheral blood and lymph nodes (LNs) of SIV-infected/uninfected Chinese rhesus macaques. SIV-infected macaques had significantly higher percentages of CD8+CD69+ and CD8+HLA-DR+ T cells in all these anatomical compartments than uninfected macaques. LNs that located close to the gastrointestinal (GI) tract (colon, mesenteric, and iliac LNs) of SIV-infected macaques had profoundly lower numbers of CD4+ T cells, but no significant difference in expression of activation marker (CD8+CD69+ and CD8+HLA-DR+) as compared with the peripheral lymphatic tissues (axillary and inguinal LNs). The CD4/CD8 ratios were negatively correlated with the activation of CD8+ T cells in the overall LNs, with further associations with CD8+HLA-DR+ in GI LNs while CD8+CD69+ in peripheral LNs. These observations demonstrate that the increase of CD8+ T cell activation is a contributing factor for the decline of CD4/CD8 ratios in GI system.