When CAR T cells expressing mCD40 L are injected into an NSG mouse model, CD40 L-CD40 interaction between the CAR T cells and monocyte-macrophages is associated with CRS, and this interaction correlates with the severity of the CRS19, thus suggesting that CAR T cells may regulate the production of cytokines in macrophages through CD40L-CD40 signaling. The gene discussed is CD40; the disease is congenital rubella syndrome.