CD4 and congenital rubella syndrome: Indeed, they allow testing human CAR-T cell products in mice while ensuring proper crosstalk with other human immune cells and cytokines, which are crucially involved in supporting CAR-T cell function and in exacerbating CAR-T cell-related toxicities, like CRS and ICANS.27 28 45 For these reasons, we exploited the HuSGM3 mouse model to evaluate CD4 and CD8 CAR-T cell performances.