Effect of LEDGF/p75 on replication capacity of newly produced HIV-1 virions. (A) Replication of HIV+ (virus produced in WT Nalm 6 cells) and HIV− (virus produced on Nalm−/− cells), after normalization for p24, was monitored in Nalm+/c cells by p24 ELISA. (B) Thin section TEM images of HIV-1 particles generated by NL4.3 infected Nalm+/c or Nalm−/− cells. Arrows indicate immature particles (scale bar = 200 nm). (C) Viral particles were classified into mature particles with conical capsid (black bars), immature particles (white bars), and budding particles (gray bars), and the percentage of each category was calculated relative to the total number of particles (HIV−; 150, HIV+; 350 viral structures per condition) analyzed.