The Interface Between Biochemistry and Immunology: Metabolic Regulation of Immune Cell

Background: The functional state of immune cells is intricately linked to their metabolic programs, which dynamically adjust in response to environmental cues and immunological demands. The interface between biochemistry and immunology—often termed immunometabolism—has revealed that metabolic pathways are not merely passive providers of energy and biosynthetic precursors, but active regulators of immune cell fate, activation, and effector functions. Disruption in these biochemical processes contributes to immune dysregulation in cancer, autoimmunity, and chronic inflammation. Methods and Results: This review synthesizes recent advances in understanding the metabolic control of immune cells, including T cells, macrophages, dendritic cells, and natural killer cells. Upon activation, naive T cells shift from oxidative phosphorylation to glycolysis to meet increased energy demands, while regulatory T cells maintain mitochondrial respiration to support suppressive function. Similarly, pro-inflammatory M1 macrophages rely on glycolytic flux and truncated TCA cycle intermediates, whereas anti-inflammatory M2 macrophages favor fatty acid oxidation and oxidative metabolism. Key biochemical regulators include mTOR, AMPK, HIF-1α, and SIRT1, which integrate nutrient availability with transcriptional and epigenetic reprogramming. Cross-talk between amino acid metabolism (e.g., arginine, tryptophan) and immune signaling modulates tolerance, activation, and antigen presentation. Metabolites such as succinate, itaconate, and lactate also serve as immunomodulatory signals. Technological advances in metabolomics and single-cell profiling have enabled unprecedented resolution of immune-metabolic networks. Conclusion: The metabolic architecture of immune cells is a critical determinant of their functional specialization and adaptability. Leveraging insights from biochemical regulation offers novel therapeutic opportunities to modulate immune responses in a context-specific manner, paving the way for precision immunotherapies.