The infiltration and activity of TILs in tumors are influenced by various factors, including the tumor's genetic mutations, the tumor microenvironment, and the overall immune status of the patient. Specific genetic changes in tumor cells can either promote or inhibit the recruitment of TILs. Additionally, the presence of immune-suppressive cells, such as regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs), within the tumor microenvironment can modulate TIL activity.
