Second, infection experiments revealed that all three C-terminal mutant viruses (KK215,9AA, KK240,4AE and RK263,4AA) exhibited more severe defect of induction of β-Gal positive cells and luc activity, as compared to an IN class 1 mutant D64E virus, in CD4+ HeLa-β-Gal cells, dividing and non-dividing C8166 T cells. This evidence concerns the gene CD44 and infection.