NCAM1 and genotype: To investigate whether differential NKG2D expression within genotype 1 infections on CD56+CD3+ lymphocytes influences IFN-γ production, we analyzed IFN-γ production from CD56+CD3+ lymphocytes after stimulation by PMA/ionomycin (gating strategy in Fig 6A), a known strong stimulator of human peripheral blood CD56+CD3+ lymphocytes [39].