IL6 and congenital rubella syndrome: Secretion of GM-CSF and IL-1β (light blue) rises almost immediately after infusion of CAR T cells and peaks rapidly followed by an equally rapid decrease, IL-6 secretion (purple) starts to increase shortly after and peaks at the same time as CRS (orange) is most likely to occur; after which, IL-6 drops but remains on an elevated level for some time.