Background HIV-1 infected and immune-activated macrophages and microglia secrete neurotoxins,such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β),which play major role in the neuronal death.It has been shown that different HIV-1 variants have varying abilities to elicit secretion of TNF-α by peripheral blood mononuclear cell (PBMC); however,whether the difference of gp120 gene could affect the secretion of TNF-α and IL-1β by glial cells is unknown.The aim of this study was to explore the association between gene diversity and induction of neurotoxic cytokines.Methods In this study,we constructed retroviral vectors MSCV-IRES-GFP/gp120 using HIV-1 gp120 genes isolated from four different tissues of one patient who died of AIDS dementia complex (ADC).Recombinant retroviruses produced by cotransfection of MSCV-IRES-GFP/gp120,pCMV-VSV-G and pUMVC into 293T cells were collected and added into U87 glial cells.Concentrations of TNF-α and IL-1β secreted by transduced U87 cells were assayed with ELISA separately.Results The four HIV-1 gp120 were in the different branch of the neighbor-joining tree.Compared to the pMIG retrovirus (gp120-negative) or U87 cells,all the gp120-positive recombinant retroviruses induced more TNF-α (P ＜0.01) and IL-1β (P ＜0.01).In addition,compared with the L/MIG retrovirus,all the three brain gp120-positive recombinant retroviruses induced less TNF-α (P ＜0.01) and IL-1β (P ＜0.01).Conclusions HIV-1 gp120 could induce U87 cells secret more TNF-α and IL-1β again.The more important is that difference of HIV-1 gp120,especially cell-tropism may account for the different ability in eliciting secretion of TNF-α and IL-1β,which might supply a novel idea helping understand the pathogenesis of ADC.