Anti-CD35/CR1 Antibody Picoband® Fluoro488 Conjugated

Complement receptor type 1 (CR1) also known as C3b/C4b receptor or CD35 (cluster of differentiation 35) is a protein that in humans is encoded by the CR1 gene. This gene is a member of the receptors of complement activation (RCA) family and is located in the 'cluster RCA' region of chromosome 1. The gene encodes a monomeric single-pass type I membrane glycoprotein found on erythrocytes, leukocytes, glomerular podocytes, and splenic follicular dendritic cells. The Knops blood group system is a system of antigens located on this protein. The protein mediates cellular binding to particles and immune complexes that have activated complement. Decreases in expression of this protein and/or mutations in its gene have been associated with gallbladder carcinomas, mesangiocapillary glomerulonephritis, systemic lupus erythematosus and sarcoidosis. Mutations in this gene have also been associated with a reduction in Plasmodium falciparum rosetting, conferring protection against severe malaria. Alternate allele-specific splice variants, encoding different isoforms, have been characterized. Additional allele specific isoforms, including a secreted form, have been described but have not been fully characterized.

Membrane immune adherence receptor that plays a critical role in the capture and clearance of complement-opsonized pathogens by erythrocytes and monocytes/macrophages (PubMed:2963069) . Mediates the binding by these cells of particles and immune complexes that have activated complement to eliminate them from the circulation (PubMed:2963069) . Acts also in the inhibition of spontaneous complement activation by impairing the formation and function of the alternative and classical pathway C3/C5 convertases, and by serving as a cofactor for the cleavage by factor I of C3b to iC3b, C3c and C3d, g, and of C4b to C4c and C4d (PubMed:2972794, PubMed:8175757) . Plays also a role in immune regulation by contributing, upon ligand binding, to the generation of regulatory T cells from activated helper T cells (PubMed:25742728) . (Microbial infection) Acts as a receptor for Epstein-Barr virus.

1. Jacobson AC, Weis JH (Sep 2008) . Comparative functional evolution of human and mouse CR1 and CR2. J. Immunol. 181 (5) : 2953–9. 2. Khera R, Das N (February 2009) . Complement Receptor 1: Disease associations and therapeutic implications. Molecular Immunology. 46 (5) : 761–772. 3. Moulds JM, Nickells MW, Moulds JJ, Brown MC, Atkinson JP (May 1991) . The C3b/C4b receptor is recognized by the Knops, McCoy, Swain-langley, and York blood group antisera. J. Exp. Med. 173 (5) : 1159–63.