Sialic acid-binding Ig-like lectin 1 (Siglec-1) (SIGLEC1)

Siglec-1, also known as Sialoadhesin or CD169, is a large transmembrane glycoprotein and a member of the sialic acid-binding immunoglobulin-like lectin family. It is exclusively expressed on specific subpopulations of macrophages, such as those in the splenic marginal zone, lymph node subcapsular sinus, and peritoneal cavity. Its primary physiological role involves the recognition of sialylated ligands for cell-cell adhesion and the clearance of endogenous glycoproteins, including the muscle-type isoenzyme of lactate dehydrogenase (LDH-5). Siglec-1 is a critical entry receptor for the Lactate dehydrogenase-elevating virus (LDV) in mice and has been implicated in the capture and trans-infection of other enveloped viruses like HIV-1 and Ebola. In clinical contexts, it serves as a biomarker for macrophage activation in inflammatory and autoimmune diseases, and its role in viral persistence makes it a subject of study for preventing laboratory contamination in murine research models.

Other names

SialoadhesinCD169Lactate dehydrogenase-elevating virus receptorLDV receptorTrypsin-sensitive Ia-related receptorSN

Antibodies or ligands bind to the N-terminal V-set domain of Siglec-1 to block viral attachment and internalization or to modulate macrophage-mediated immune responses.