CASP8 and lymphopenia: In addition, Casp8ΔE385/ΔE385Ripk3−/− and Casp8ΔE385/ΔE385Mlkl−/− mice developed lymphopenia with severe splenomegaly instead of the lymphoproliferative disease as observed in Casp8−/−Ripk3−/− and Casp8−/−Mlkl−/− mice.