When X4- or R5-tropic HIV-1 viral particles were incubated with CEM.NKR-CCR5 permissive cells, HIV-1 entry and infection was significantly impaired in gelsolin-EGFP-expressing cells as compared with control cells (Figure 2D), with a similar impairment of both the X4- or R5-tropic HIV-1 viral strains (Figure 2D; 54% and 58% of X4-tropic and R5-tropic infection, respectively). This evidence concerns the gene CCR5 and infection.