1 Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of BioactivePeptides of Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming Yunnan 650223, China2 University of Chinese Academy of Sciences, Beijing 100049, China3 Kunming Primate Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming Yunnan 650223, China
This work was partly supported by grants from the National Natural Science Foundation of China (81471620; 81671627; 81571606; 81601808; 81172876; U0832601), the National Basic Research Program of China (2012CBA01305), the 13th Five-Year Key Scientific and Technological Program of China (2017ZX10304402-002-004; 2017ZX10202102-001-005), and the National Key Research & Development (R & D) Plan 2016YFC1201000)
Parasites can increase infection rates andpathogenicity in immunocompromised humanimmunodeficiency virus (HIV) patients. However, invitro studies and epidemiological investigationsalso suggest that parasites might escapeimmunocompromised hosts during HIV infection.Due to the lack of direct evidence from animalexperiments, the effects of parasitic infections onimmunocompromised hosts remain unclear. Here,we detected 14 different parasites in six northernpig-tailed macaques (NPMs) before or during the50th week of post-simian immunodeficiency virus(SIV) infection by ELISA. The NPMs all carriedparasites before viral injection. At the 50th week afterviral injection, the individuals with negative resultsin parasitic detection (i.e., 08247 and 08287) werecharacterized as the Parasites Exit (PE) group, withthe other individuals (i.e., 09203, 09211, 10205, and10225) characterized as the Parasites Remain (PR)group. Compared with the PR group, the NPMs in thePE group showed higher viral loads, lower CD4+ Tcells counts, and lower CD4/CD8 rates. Additionally,the PE group had higher immune activation andimmune exhaustion of both CD4+ and CD8+ T cells.Pathological observation showed greater injury tothe liver, cecum, colon, spleen, and mesentericlymph nodes in the PE group. This study showedmore seriously compromised immunity in the PEgroup, strongly indicating that parasites might exit animmunocompromised host.