Development of Epigallocatechin Gallate as an HIV-1 Microbicide Agent: Impact on Dendritic Cell Innate Immune Responses (46.12)

Langerhans cells (LC) and monocyte-derived dendritic cells (MDDC), the first line of defense against viral infection, initiate innate immune responses via toll-like receptors (TLR). Previously, we showed inhibition of HIV-1-gp120 binding to CD4 on T cells by the green tea catechin, epigallocatechin gallate (EGCG). We present evidence of EGCG inhibition of the mucosal route of HIV-1 without alteration of dendritic cell (DC) innate immune responses. Methods utilized were CD34+ hematopoietic stem cells and CD14+ cells differentiated to LC and MDDC, respectively, isolated from peripheral blood of HIV-1 seronegative donors, flow cytometry of HIV-1-gp120 binding and TLR profiling with RT-PCR, radioisotope assays for antigen (Ag) studies, MTT assay for cytotoxicity, p24 ELISA for HIV-1 infectivity studies and statistical significance by Student’s t test. EGCG significantly inhibited HIV-1 infectivity in LC in a dose-dependent manner; 100%(50uM;p