HIV-Captured DCs Engage in Prolonged Contacts with T Cells in a gp120:CD4-Dependent Manner
(A) Control or HIV-captured DCs were co-cultured with T cells and embedded into a collagen matrix for 4 h. T cells were extracted after collagenase treatment and incubated for an additional 48 h to measure productive infection. Normalized fold increase in T cell infection in the indicated conditions are shown. Data are from three independent experiments. Mean ± SEM are shown. Ral, raltegravir. ∗∗∗p < 0.01, Unpaired Student's t test.
(B) Time-lapse micrographs of DC:T cell contacts that are defined as brief or prolonged interactions. Time stamp are in min:sec of the movie recordings.
(C) DC:T cell contact duration in the presence of wild-type or HIV-iGFPΔEnv. Red lines indicate median values. αCD4, anti-CD4 antibody. ∗∗∗∗p < 0.001, Mann-Whitney U test. Data from ten independent experiments are shown (n = 1,172 total DC:T cell contact events).
(D) Percent distribution of DC:T cell contact times defined as brief (>7 min; black), prolonged (7–17 min; blue), or stable (>17 min; red) are shown.
(E) Representative of instantaneous speeds of a T cell during a brief, prolonged, or stable contact with a DC is shown. Red shaded area represents a DC-T cell contact event. Data from two independent experiments are shown (n = 3 of total DC:T cell contact events).
(F) Mean T cell velocity during brief, prolonged, or stable contacts with HIV-captured DCs. Red lines indicate median values. Data from three independent experiments are shown (n = 75 total cells). ∗∗∗∗p < 0.001, Mann-Whitney U test.
(G) Mean T cell velocity during contact with control, wild-type HIV, or HIV-iGagΔEnv-pulsed DCs. Mean velocity was defined as the average speeds of a single T cell track contacting a DC. Red lines indicate median values. Data from three independent experiments are shown (n = 171 total cells). ns, not significant. ∗∗∗∗p < 0.001, Mann-Whitney U test.