Flow cytometric analysis of CD4 T cell subpopulations. Fresh
total PBMC isolated from healthy uninfected individuals were stained
with antibodies to CCR5 (FITC), CXCR4 (PE), CD3 (Cy5PE), CD4 (Cy7PE),
CD8 (Cy5.5APC), CD45RA (Cascade blue), and CD62L (Cy5.5PE) as described
in Materials and Methods. Naive, M1 and M2 CD4 T cells
are identified on the basis of expression of CD45RA and CD62L
(Upper Left). The other plots show the expression of
CXCR4 and CCR5 on gated subsets of CD4 T cells. Numbers indicate the
percentage of each subset that expresses CCR5. Cells above the dashed
line express CXCR4; as expected, a majority of all subsets are
CXCR4+. The antibody for CCR5 (2D7) binds competitively
with CCR5 ligands; however, there are no chemokines in these
unstimulated cultures so no blocking can occur.