Figure 6.

LFA-1:ICAM-1 Binding Stabilizes Stable DC:T Cell Contacts and Facilitates Viral Transmission

(A) Flow cytometry analysis of high-affinity LFA-1 expression (mAb clone 24) on T cells after co-culture with HIV-captured DCs. Data are normalized to no virus DC:T cell controls. Data from two healthy donors. Mean ± SEM are shown. ∗∗p < 0.01, Unpaired Student's t test.

(B) DC:T cell contact duration in the presence or absence of LFA-1:ICAM-1 interactions. ICAM-1, anti-ICAM-1 antibody; αLFA-1, anti-LFA-1 antibody. Red lines indicate median values. ∗∗p < 0.01, ∗∗∗p < 0.001, Mann-Whitney U test. Data from eight independent experiments are shown (n = 957 total DC:T cell contact events).

(C) Percent distribution of DC:T cell contact times defined as brief (>7 min; black), prolonged (7–17 min; blue), or stable (>17 min; red) from data in (B) are shown.

(D) Percent normalized T cell infection with the indicated antibody blockade. Data are from two independent experiments. Mean ± SEM are shown. n.s., not significant. ∗∗p < 0.01, Unpaired Student's t test.

(E) IPA identified biological pathways that were significantly (p < 0.01) upregulated (Z score > 1) in T cells co-cultured with wild-type HIV-pulsed DCs (T cells co-cultured with HIV-iGagΔEnv-pulsed DCs set as background controls). The p value (red line), calculated with the Fischer's exact test, reflects the likelihood that the association between a set of activated kinases and a biological function is significant (p value ≤ 0.05).