Figure 2

Immunofluorescence microscopy demonstrating reduced cell surface expression of CXCR4 in HIV-1 infected RH9 cells. Panel A: Immunofluorescence staining control with isotype-matched monoclonal antibody. Panel C: CXCR4 immunofluorescence staining of H9 cells. Panels E and G: CXCR4 immunofluorescence staining of H9 cells acutely infected by HIV-1. Panels B, D, F and H show phase contrast images of the same fields of cells shown in left panels. The fluorescent syncytial cell in panel G is representative of a minor population of cells in the infected culture (<10%) with a CXCR4 surface distribution similar to uninfected cells.