HIV :: p21 stops HIV-1 in its tracks in hematopoietic stem cells
Hematopoietic stem cells (HSCs) are one of the few cell types able to resist infection with HIV-1 despite expressing the cell surface molecules to which HIV-1 binds before entering a cell. In a study that appears in the February issue of the Journal of Clinical Investigation, researchers from Harvard Medical School, Boston, show that HSC expression of a protein known as p21Waf1/Cip1/Sdi1 (p21) is required for HSCs to be resistant to infection with HIV-1.