Palmitoylation and association with LCK contribute to the enrichment of CD4 in lipid rafts.
Cell membrane. Localizes to lipid rafts. Removed from plasma membrane by HIV-1 Nef protein that increases clathrin-dependent endocytosis of this antigen to target it to lysosomal degradation. Cell surface expression is also down-modulated by HIV-1 Envelope polyprotein gp160 that interacts with, and sequesters CD4 in the endoplasmic reticulum.
Overlay histogram showing peripheral blood lymphocytes stained with ab18280 (red line). The cells were incubated with the antibody (ab18280, 1/20 dilution) for 30 min at 4ºC. Isotype control antibody (black line) was mouse IgG1 [ICIGG1] (ab91353, 2µg/1x106 cells) with secondary antibody DyLight® 649 goat anti-mouse IgG (H&L) (ab96882) at 1/200 dilution for 30 min at 4ºC. Acquisition of >5,000 events was performed gating on peripheral blood lymphocytes.