IFNG and pertussis: NK cells from both HCMV+ and HCMV− donors responded to pertussis and H1N1 (with or without LCC; Fig. 2); however, NK cell responses to these two vaccines (whether defined as CD25+, CD25+IFN-γ+, or CD107a+) were significantly lower among HCMV+ donors than among HCMV− donors (Fig. 2A and 2B).