Trem2 (triggering receptor expressed on myeloid cells 2), a trigger receptor 2 expressed by myeloid cells, is an important immunoregulatory receptor, mainly expressed on the surface of myeloid cells such as macrophages and microglia, and plays a key role in maintaining immune homeostasis, regulating inflammation and the occurrence and development of various diseases. Trem2 is highly expressed in tumor-associated macrophages (TAMs), which plays a role in promoting tumor by inhibiting anti-tumor immunity and promoting tumor angiogenesis, thus becoming a potential target of tumor immunotherapy. The protein has glycosylation modification.