HLA-DRA and major depressive disorder: Furthermore, neither transcriptions of microglial protein tyrosine phosphatase receptor type C (PTPRC), CX3CR1, P2RY12, HLA-DRA, TREM2, integrin subunit alpha M (ITGAM; CD11B), nor translocator protein (TSPO) were elevated in non-suicidal patients with MDD [76].