ABSTRACT
Objective To study the effect of repeated rectal exposure of low -dose simian immunodeficiency virus on the systemic cellular immunity in monkeys .Methods Eight 3-to 4-year old rhesus macaques ( Macaca mulatta) (male:female 1:1) were used in this study.The monkeys were inoculated with 10 TCID50 SIVmac239 virus through rectum twice a week for consecutive 6 weeks to establish a multiple rectal exposure model of SIVmac 239 virus infection.Then, plasma viral load, CD4+ T cell count, T cell subsets and IFN-γsecretion of the experiment monkeys were determined . Results Low-dose SIVmac239 virus induced some changes in the immune system through the rectal mucosa , but didn’t induce typical infection.Repeated rectal mucosal low-dose virus exposure can activate the cellular immune system . Conclusions This study defines the effect of repeated low -dose simian immunodeficiency virus exposure on the systemic cellular immunity, and provided basic information for HIV-1 vaccine research.