MAVS and neoplasm: However, most of these results have been generated from transfected tumour cells in vitro, and less is known about any in vivo consequences.3, 19, 23 New data obtained using unrelated RNA viruses suggest that IPS-1 does not influence adaptive immune responses.24, 25 Hence, although it is clear that the NS3/4A protein in vitro inhibits innate signalling through IPS-1, it is not known if this affects the adaptive immune responses.