The results in Fig. 2A and Table 2 confirm previous observations [4,6,10,11] of almost no detectable viral cDNA integration in LEDGF/p75-knockdown cells (HeLaP4/shp75Cl15 cells [27]) infected by a WT HIV-1 (in this case at a multiplicity of infection (MOI) of 1.0). Here, PSIP1 is linked to infection.