Figure 4. Anti-HIV-1 activities of monomeric and trimeric C34 and N36 peptides.
HeLa cells expressing envelope glycoproteins from either HIV-1 LAI (X4-tropic virus) (A,B) or HIV-1 ADA (R5-tropic virus) (C,D) were incubated with HeLa cells expressing human CD4 receptor and CXCR4 or CCR5 HIV-1 co-receptors in the presence of monomeric or trimeric C34 peptides used at 5 × 10−8 M that had previously been incubated with escalating amounts of monomeric or trimeric N36 peptides (10−11–10−6 M) and vice versa. After 20 h, the capacity of N36 peptide to cancel the C34 anti-fusion activity was evaluated. ‘mock’ corresponds to the syncytia formation obtained in the absence of peptide inhibitors but including the same medium as that used for the solubilization of the peptide inhibitor tested. Experiments were performed in triplicate and repeated three times. A representative experiment is shown as mean ± standard deviation. ns, nonsignificant.