IFNAR1 and neoplasm: As IFNAR1 KO CAR T cells were at least partially resistant to the VSVmIFNβ induced attrition in vivo, and were also resistant to CAR expression dysregulation in vitro, we hypothesized that these type I IFN insensitive transgenic CAR T cells would provide superior tumor control in combination with VSVmIFNβ over CAR T cells generated from WT donor mice.