Cellular Nucleotide Availability Does not Affect the Rate of HIV-1 Recombination. Note the enhancement of HIV-1 infection in macrophages but not in peripheral blood lymphocytes, indicating that dNTP levels are limiting in the former but not the latter.

Peripheral blood lymphocytes were stimulated with PHA-L and IL-2 (50 units/ml) for 4 days before infection. Macrophages were prepared from peripheral blood monocytes by adherence to plastic dishes, cultured in M-CSF (1,000 units/ml) for 5 days before infection, and then analyzed 4 days after infection. Nucleosides (2'-deoxycytidine, 2'-deoxyadenosine, 2'-deoxyguanosine, and thymidine) (Sigma) at the indicated amounts (values are for each nucleoside) were added to the culture medium at the time of infection with copackaged NLENY1-ES-internal ribosome entry sequence (IRES) and NLENC1-ES-IRES pseudotyped with VSV-G protein. For flow analysis of macrophages, gating was on cells positive for CD13 and CD14.