Binding of mAb ACT-1, HIV-1 gp120, and cyclic V2 peptides to RMPI8866 cells.

<p><b>(A)</b> RPMI8866 cells (0.5 x10⁶) were incubated with 1 μg APC labeled ACT-1 (α4β7 specific antibody). Antibody binding was measured by flow cytometry and is presented as a histogram. Over 99% of the RPMI8866 cells expressed α4β7 integrin. Unstained cells (grey shading) and isotype control antibody (solid line) were used as controls. <b>(A and C)</b> Histograms show the binding of CHO-expressed HIV-1 gp120 (2.5 μg, blue line panel <b>B),</b> biotin labeled cyclic V2 TH023 peptide (1μg and 5 μg; black and orange lines, respectively; panel <b>C</b>), and biotin labeled cyclic V2 TH023 -fully scrambled peptide (SCR; 1 μg and 5 μg; blue line and green line; panel <b>C</b>) to RMPI8866 cells. Polyclonal mouse anti-gp145 antibody followed by goat anti-mouse-Texas Red was used to visualize the gp120 protein binding while the V2 peptides were visualized with neutrAvidin-PE. Cells treated with only anti-mouse-Texas Red (red line, panel <b>B</b>) and unstained cells (red line, panel <b>C</b>) were used as controls in addition to the fully scrambled V2 peptide (blue and green line, panel <b>C</b>). Representative histograms are shown for panels <b>A</b>, <b>B</b>, and <b>C</b> (n = 2).