Interestingly, emerging work has implicated a preferential role of CD4+ T cells, but not CD8+ T cells, in the pathogenesis of CRS [55, 56], which is congruent with our observations of ruxolitinib-mediated prevention of life-threatening cytokine-associated toxicities in TSLPRCART-treated animal models. This evidence concerns the gene CD8A and congenital rubella syndrome.