TAMs infiltrated in the TME are one of the important components in regulating tumor immunity, and they can interact with TRM cells to regulate their maintenance.665,666 In terms of TME, a study found that in early lung cancer, M1 type-TAMs enhanced the infiltration and maintenance of CD8+TRM cells in tumor sites by producing CXCL9 and fatty acids, which CD8+TRM cells depend on for survival and functions.667 In addition, another study also indicated that IL-15 secreted by TAMs contributed to the persistent residency of TRM cells in BC.637. The gene discussed is CXCL9; the disease is neoplasm.