TREM2 encodes a membrane protein that forms a receptor signaling complex with the TYRO protein tyrosine kinase binding protein. Triggering Receptor Expressed On Myeloid Cells 2 functions in immune response and may be involved in chronic inflammation by triggering the production of constitutive inflammatory cytokines. Defects in this gene are a cause of polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL). Alternative splicing results in multiple transcript variants encoding different isoforms.