Could CD4 Capture by T Cells Play a Role in HIV Spreading?
Figure 4
CD8+ T cells having acquired CD4 induced syncytia formation in infected MOLT-4 cultures. (A) Transmission microscopy analysis (low power fields) of cultures in which anti-CD3 anti-CD28-activated CD8+ T cells that had been cocultured with HEK cells either expressing CD4-GFP (middle and lower panels) or not (upper panels), were then mixed with uninfected MOLT-4 cells (left panels) or HIV-infected MOLT-4 cells either in the absence (middle panels) or the presence (right panels) of the anti-CD4 mAb Leu3a. The controls shown on the bottom panels correspond to T cells that have been cocultured with HEK cells expressing CD4-GFP, but had not previously been activated with the anti-CD3 + anti-CD28 mAbs, (CTROL) white arrows indicate the positions of syncytia. (B) Quantification of syncytia in different randomly selected high power fields. Data are mean SD values of at least four different fields. Note that syncytia formation was never detected when uninfected MOLT-4 cells were used, whatever the condition tested. Asterisks denote statistically significant differences between activated and control CD8+ T cells cocultured with HEK-CD4-GFP cells (, test) and significant inhibition was induced by Leu3a (, test).
