Notably, the loss of CaMKKβ activity inhibited the ability of tilapia leukocytes to express Perforin A, Granzyme B, IFN-γ, TNF-α, and IL-6 (Appendix Fig. S7F) and reduced the frequency of Granzyme B-producing T cells (Appendix Fig. S7G,H), consequently impairing the ability to control bacterial infection (Appendix Fig. S7I). Here, GZMB is linked to bacterial infectious disease.