Figure 1. Expression of CD4, CXCR4, and CCR5 in HRCEC. CXCR4 (C and D) and CCR5 (E and F) receptors were positive on the cell surface of HRCEC, but the CD4 receptor (A and B) was negative. A, C, and E were by immunocytochemistry; B, D, and F were by immunofluorescent staining. To focus on specific markers in immunofluorescent staining, 4', 6-diamidino-2-phenylindole (DAPI) nuclear staining on B, D, and F was not displayed. Three independent experiments were performed.