KLRB1 and colorectal carcinoma: To determine the distribution of MAIT cells in CRC patients, we analyzed circulating and tissue-infiltrating MAIT cells by staining with anti-TCR Vα7.2 and anti-CD161 or anti-IL-18Rα2, 3, because CD161 is expressed by the majority of NK cells and diverse subsets of T lymphocytes, including γδ T, most NKT and MAIT cells37.