Detection of elevated serum beta-chemokine levels in seronegative Chinese individuals exposed to human immunodeficiency virus type 1

The mutations in the CCR5 coding region, such as CCR5 Delta 32 and CCR5m303 , that suppress the transmission of human immunodeficiency virus (HIV) type 1 do not exist in Chinese people. However, 9 Chinese subjects in Taiwan wi th histories of multiple sexual exposures to HIV remained uninfected, sugge sting that certain anti-HIV factors do indeed exist. Experiments were there fore designed to investigate the immune mechanism that protects this cohort against HIV infection. Peripheral blood samples from these 9 subjects and 7 healthy people who had not been exposed to HIV were obtained for the quan titation of the levels for beta -chemokines and interleukin 16 (IL-16) in s erum samples or secreted by peripheral blood lymphocytes. Significantly hig her serum levels for nearly all 3 beta -chemokines, regulation on activatio n, normal T cell-expressed and secreted, macrophage inflammatory protein (M IP)-1 alpha, and MIP-1 beta (P < .05, P<.05, and P = .05, respectively), bu t not IL-16, were detected in the 9 HIV-uninfected subjects as compared wit h control subjects. The result suggests that among the host genes and cellu lar factors thus far identified, beta -chemokines are the major HIV-suppres sive factors that protect Chinese people from infection with HIV.