IL6 and congenital rubella syndrome: CRS is the most common adverse event following CAR T-cell therapy, with a prevalence of 75% to 100% in patients (Table 1), which refers to a systemic inflammatory response mediated by the release of excessive cytokines, including IL-6, IL-1, IL-8, IFN-γ, GM-CSF, macrophage inflammatory protein-1B (MIP-1B), and monocyte chemoattractant protein-1 (MCP-1) (82, 83).