The cytokine profile of patients undergoing CD19 CAR T-cell therapy has been associated with the severity of CRS; higher levels of IFN-γ, IL-6, IL-8, sIL-2Rα, sgp130, sIL-6R, MCP-1, MIP-1α, MIP-1β, and GM-CSF have been reported in patients with grade 4–5 CRS [9]. The gene discussed is IL6ST; the disease is congenital rubella syndrome.