Capture and transmission of HIV-1 by the C-type lectin L-SIGN (DC-SIGNR) is inhibited by carbohydrate-binding agents and polyanions

It was recently shown that capture of HIV-1 by DC-SIGN-expressing cells and the subsequent transmission of HIV to CD4+ T-lymphocytes can be prevented by carbohydrate-binding agents (CBAs), whereas polyanions were unable to block virus capture by DC-SIGN. In this study, we could show that a short pre-exposure of HIV-1 to both mannose- and N-acetylglucosamine (GlcNAc)-specific CBAs or polyanions dose-dependently prevented virus capture by L-SIGN-expressing 293T-REx/L-SIGN cells and subsequent syncytia formation in co-cultures of the drug-exposed HIV-1-captured 293T-REx/L-SIGN cells and uninfected C8166 CD4+ T-lymphocytes. Additionally, the inhibitory potential of the compounds against L-SIGN-mediated HIV-1 capture and transmission was more pronounced than observed for DC-SIGN-expressing 293T-REx/DC-SIGN cells. The excess value of CBAs and polyanions to prevent HIV-1 capture and transmission by DC-SIGN and L-SIGN-expressing cells to susceptible T-lymphocytes could be of interest for the development of new drug leads targeting HIV entry/fusion.