HIV-1 Nef induced variable levels of chemokine receptor downregulation in different cell types.

*For each type of cell, Nef effect on the expression of the indicated CKR was evaluated along with that of CD4 (endogenous or plasmid expressed).**CEM-NKR cell line expressing CCR5 and CXCR4 was used.#CXCR4 was analyzed in a K562 CXCR4 cell line.Cells were transfected with IRES plasmid encoding Nef and or NefXho (null) and GFP. Cell surface expression of endogenous CCR2B, CCR5 (fresh PBLs, monocytes), CCR7 (PBMCs only), CXCR4 (fresh PBLs, monocytes, Jurkat and CEM cells), or from expression plasmids for the indicated CKRs (CHO or K562 or Jurkat) was evaluated by flow cytometry of GFP gated cells. MFV for GFP (+) and NefXho (null) population was set to 100 in each case. The downregulation was significant when compared to endogenous or plasmid expressed receptor levels for all the CKRs and CD4 (p$.The data in the table represents mean ± standard deviation. (n = 4, for PBMCs, monocytes, CHO and K562 cells; and n = 3 for CEM and n = 4 for Jurkat cells).