RIPK3 and lymphopenia: Consistently, lymphopenia was recapitulated in the Ripk3−/−Casp8ΔE385/ΔE385 and Mlkl−/−Casp8ΔE385/ΔE385 recipients characterized by CD8+ T cell deficiency in blood and decreased B cells, T cells, and their subsets in the spleen, bone marrow, and blood (Figs. 6E, F and S6D).