Objective: To determine the relative resistance to HIV-1 infection of CD4 + T lymphocytes in HIV-exposed seronegative individuals (ESNs) in China.
Methods: HIV primary isolates were obtained from peripheral whole blood of HIV-infected persons. CD4 + T lymphocytes of Chinese ESNs were separated from peripheral blood mononuclear cells with magnetic cell sorting (MACS). The purified CD4 + T lymphocytes were cocultured with HIV primary isolates. The p24 level was detected and the culture medium was refreshed every 3 days within 2 weeks.
Results: For M tropic HIV strains, p24 level was significantly lower in ESN group than in control group (P < 0.05); for some M tropic HIV strains, even no p24 replicated in ESN group. However, T tropic virus strains had no significant difference between these two groups (P > 0.05).
Conclusion: CD4 + T lymphocytes of Chinese ESNs may possess relative resistance to M tropic HIV strains, which may be one of the main influencing factors that result in ESN.