Johns Hopkins Medicine Mar 31 2026 A research team from the Johns Hopkins Kimmel Cancer Center, its Bloomberg~Kimmel Institute for Cancer Immunotherapy and the Johns Hopkins Bloomberg School of Public Health have discovered how the immune system's CD8+ T cells use the nutrient cysteine to control two essential functions that compete for this resource - the immune cell's ability to multiply and its ability to kill cancer cells. The study, published March 31 in  Cell , shows that cysteine - an