CD4 and congenital rubella syndrome: In Dendritic cell (DC) type 1 (DC1)-driven autoimmunity, targeting X-C motif chemokine receptor 1 (XCR1) CAR T cells deplete DC1 across multiple organs in mouse models (including inguinal and cervical lymph nodes, spleen, lung, and liver) and inhibit Th1 driven EAE progression; DC1 depletion increases DC2 without altering total dendritic cells; CD4 XCR1 CAR T cells produce higher pro inflammatory cytokines (TNF α, IL 27, IL 10) than CD8 XCR1 CAR T cells, indicating higher CRS risk, and the approach remains largely proof of concept requiring further safety evaluation (72).