TNF and cytomegalovirus infection: Interestingly, IL-12 has been shown to be required for expansion of adaptive NK cells in response to murine cytomegalovirus infection (Sun et al, 2012), while a stimulatory effect of TNFα (Khan et al, 2023) and potential inhibition of cytotoxic activity of NK cells by IL-6 (Wu et al, 2019; Lee et al, 2023) has been reported.