Rockefeller study links dietary arginine to MHC-1 immune signaling in Cell

Rockefeller University researchers report that arginine deficiency weakens a key immune alert pathway and that restoring arginine can improve outcomes in mouse models of colon cancer and respiratory viral infection. ScienceDaily summarized the work from Sohail Tavazoie's laboratory of systems cancer biology, published in Cell with DOI: 10.1016/j.cell.2026.07.020 When arginine is scarce, cells struggle to produce MHC-1 proteins that display abnormal or foreign peptides to T cells. First author Qiushuang Wu found hundreds of proteins reduced under low arginine and traced a sharper effect on HLA genes for MHC-1: ribosomes stalled assembling the arginine-rich complex, leaving fewer surface signals. The team said a moderate amount of arginine, roughly equivalent to a couple of over-the-counter tablets, could help restore expression of genes involved in MHC-1 production. In mice, low-arginine diets led to more colon tumors while higher arginine led to fewer. With collaborators in Charles Rice's virology lab, similar dietary patterns held for influenza and SARS-CoV-2 models, and giving arginine after influenza infection also improved outcomes. Tavazoie said arginine supplementation could be tested with immunotherapies or in high-risk groups exposed to viral pathogens because the amino acid is inexpensive and widely available.