FIG. 4.

Mechanisms through which dextrans and peptide triazoles inhibit DC-SIGN-mediated HIV infection. (A) Interaction of HIV-1 with DC-SIGN expressed on dendritic cells (DCs) results in (a) infection of DCs and (b) transmission of the virus to CD4⁺ T cells and antigen presentation through MHC class II molecules. (B) Dextrans block HIV-DC-SIGN interaction resulting in a decreased infection. The quantity of HIV-DC-SIGN complex cycling through the endosome pool is decreased. (C) Interaction of peptide triazoles with HIV-1 gp120 induces irreversible breakdown and virion activation. Dextran and peptide triazole act complementarily, decreasing the amount of virus through irreversible inactivation combined with decreasing the quantity of HIV-DC-SIGN complex cycling through the endosome pool. Color images available online at www.liebertpub.com/aid