IL6 and congenital rubella syndrome: CRS typically occurred within 4–10 days post-ACT, was correlated with high IL-6 levels and peak CAR-T cell concentration post-ACT, was predominantly of G1–2, and was manageable by supportive care with antipyretics and the IL-6 receptor blocking antibody tocilizumab (Extended Data Table 2 and Extended Data Fig. 1).