Grant: Travel Awards - Institute Community Support

Our immune system includes a small but powerful group of cells called gd T cells, which help fight infections and detect cancer. These cells can carry certain receptors usually found on another immune cell type known as natural killer (NK) cells. A group of these receptors are called KIR receptors. However, the role these KIR receptors play on gd T cells was unknown. In this study, we used advanced techniques to examine gd T cells from healthy people and discovered that those with KIR receptors represent a more mature, "experienced" group of cells. These KIR+ gd T cells were better equipped to destroy target cells and had long-lasting molecular features similar to immune memory. By contrast, gd T cells without KIR receptors looked more like "naïve," or inexperienced cells. Interestingly, we found that people previously exposed to cytomegalovirus (CMV), a common lifelong virus, had higher levels of these KIR+ gd T cells. This suggests that ongoing immune challenges can shape and strengthen this subset. Overall, our findings show that KIR receptors mark a unique, more powerful type of gd T cell that could be important for fighting viruses and cancer, and may be valuable for future immunotherapies.