CD antigen CD93 is also known as Complement component C1q receptor (C1QR1). which belongs to the Group XIV C-Type lectin family, a group containing two other members, endosialin (CD248) and thrombomodulin. CD93 contains one C-type lectin domain and five EGF-like domains. CD93 is highly expressed in endothelial cells, platelets, cells of myeloid origin, such as monocytes and neutrophils. CD93 is receptor for C1q, mannose-binding lectin (MBL2) and pulmonary surfactant protein A (SPA). CD93 may mediate the enhancement of phagocytosis in monocytes and macrophages upon interaction with soluble defense collagens and may play a role in intercellular adhesion.