IFIH1 and parasitic infectious disease: Following co-culture of transduced NK cells with iRBCs for 48 h, MDA5-knocked down NK cells reduced parasitemia by 21±7% (n = 3) whereas gScrble-transduced NK cells reduced parasitemia by 63±11% (n = 3, p<0.01) (Fig 3E & 3F), suggesting a requirement for MDA5 in mediating NK cell responses to iRBCs.