AXL and neoplasm: Besides myeloid cells, the tumor microenvironment is composed of several other immune cell populations that may either participate in tumor immunity (e.g., NK cells/cytotoxic T CD8+ cells) or sustain an immunosuppressive environment [e.g., regulatory T cells (Tregs)], but to date, MerTK, Tyro3, and Axl expression in human lymphoid cells are poorly characterized.