PRF1 and infection: The most unexpected, yet in multiple independent trials reproducible finding, was a nearly abrogated expression of one of the main lytic effector proteins, perforin, in multiple cytotoxic effector populations (CD8αα+ and CD8αβ+ αβ T cells, and CD8α+ γδ T cells) 4-5 dpi during infections with both moderately and highly virulent ASFV strains.