Amino acid and cholesterol metabolism in innate immunity

Innate immune cells not only serve as the first line of defense against pathogen invasion but also play essential roles in the immune regulatory function of various diseases. Distinct innate immune cells and their subtypes exhibit unique metabolic profiles, and their activation, differentiation, and effector functions are tightly governed by a complex regulatory network involving both intracellular metabolism and metabolites derived from the surrounding microenvironment. Cholesterol and amino acids function not only as structural constituents of membranes and proteins but also as signaling mediators that fine-tune immune cell activity. Importantly, their metabolic pathways are tightly interconnected. This review focuses on amino acid and cholesterol metabolism, offering comprehensive insights into how these metabolic processes shape innate immune cell function during homeostasis or pathological conditions. We further discuss emerging metabolic targets and therapeutic strategies aimed at modulating innate immunity in the context of immune-related diseases.