MLKL and lymphoproliferative syndrome: When aged, Ripk3−/−Fadd−/−Ripk1K376R/K376R and Mlkl−/−Fadd−/−Ripk1K376R/K376R mice developed lymphoproliferative syndrome with an accumulation of CD3+B220+ lymphocytes in peripheral lymphoid organs seen in Ripk3−/−Fadd−/− and Mlkl−/−Fadd−/− mice (Fig. 7d, f, Supplementary Fig. 4d)19–22,41–43.