The approval of CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized the treatment landscape in the relapsed/refractory (R/R) setting, with multi-center trials demonstrating complete response (CR) rates of 40–54%, 67%, and 69–74% in patients with aggressive B-cell lymphomas [1,2,3], mantle cell lymphoma [4], and indolent B-cell lymphomas [5,6], respectively. Here, CD19 is linked to mantle cell lymphoma.