Without an available virus or pseudovirus, so no direct cytotoxicity assay. Generally I've seen that TNFa and IL-2 production is reported for CD4 cells and IFNg and TNFa for CD8 cells. I'm just wondering why it is done this way, considering that CD4 cells are often a significant source of IFNg? I'm designing a CyTOF panel, so all 3 of these will be measured in addition to many more markers. I was presenting my preliminary results and someone asked, but I didn't have a good answer other than this is what I usually see.