Description
CD93 or C1q receptor 1 (C1qR) is an about 120 kDa O-sialoglycoprotein that within the hematopoietic system is selectively expressed on cells of the myeloid lineage. CD93/C1qR is a highly glycosylated transmembrane protein expressed on monocytes, neutrophils, endothelial cells, and stem cells. CD93 was originally identified as a myeloid cell-surface marker and subsequently associated with an ability to modulate phagocytosis of suboptimally opsonized immunoglobulin G and complement particles in vitro. CD93/C1qR, a receptor expressed during early B-cell development, is reinduced during plasma-cell differentiation. High CD93/CD138 expression was restricted to antibody-secreting cells both in T-dependent and T-independent responses as naive, memory, and germinal-center B cells remained CD93-negative. CD93 was expressed on (pre)plasmablasts/plasma cells, including long-lived plasma cells that showed decreased cell cycle activity, high levels of isotype-switched Ig secretion, and modification of the transcriptional network. CD93 is important for the maintenance of plasma cells in bone marrow niches.
Target
CD93
Target Alias Names
C1qR, C1qR(P), C1QR1, C1qRP, CDw93, dJ737E23.1, ECSM3, MXRA4
Isotype/Mimetic
Rabbit IgG
Animal-Derived Biomaterials Used
No
Sequence Available
No
Original Discovery Method
Phage display technology
Antibody/Binder Origins
Animal-dependent discovery (in vitro display, OR immunisation pre-2020), In vitro recombinant expression