Marmoset CD32b Protein (In Vivo Grade, Ultra-Low Endotoxin) (ICH3032)

Please refer to the specific buffer information in the hardcopy of datasheet or the lot-specific COA.

This is a recombinant marmoset (Callithrix jacchus) CD32b (FcgammaRIIB) protein produced in HEK293 cells, supplied as an in-vivo-grade, ultra-low-endotoxin (<0.5 EU/mg) reagent for research use only. As a mammalian-expressed ectodomain it carries native-like folding and glycosylation, preserving the conformational epitopes and IgG-Fc binding surface needed for reliable interaction studies. It is validated for surface plasmon resonance (SPR), bio-layer interferometry (BLI) and ELISA, making it suited to kinetic and affinity characterisation of anti-CD32b antibodies, Fc-engineered therapeutics and Fc variants against the inhibitory receptor. The common marmoset is an increasingly used small non-human primate model for immunology, drug metabolism and monoclonal-antibody pharmacology, so a species-matched CD32b reagent supports cross-species Fc-receptor profiling and translational bridging between rodent, primate and human systems. Low endotoxin and bulk mg-to-gram availability allow scale-up from assay development into structure-function and screening campaigns. Note: the referenced UniProt accession is electronically annotated as marmoset FCGR2A; investigators should confirm the receptor isoform matches their application, as marmoset Fc-receptor entries are often provisional. CD32b (FcgammaRIIB, gene FCGR2B) is the only inhibitory Fc gamma receptor for IgG. Unlike the activating Fc gamma receptors, its cytoplasmic tail carries an immunoreceptor tyrosine-based inhibitory motif (ITIM). When co-clustered with the B-cell receptor or with activating ITAM-bearing receptors, the phosphorylated ITIM recruits the phosphatase SHIP-1, raising the threshold for cellular activation and dampening calcium mobilisation. On B cells this delivers a negative feedback signal that limits antibody production and enforces peripheral tolerance; on myeloid cells it restrains phagocytosis, degranulation and pro-inflammatory cytokine release. CD32b is expressed on B cells, monocytes, macrophages, dendritic cells and basophils. It is a major determinant of the in-vivo activity of therapeutic antibodies, setting the activating-to-inhibitory (A/I) receptor ratio that governs agonism, ADCC and antibody consumption, and it is itself a therapeutic target in B-cell malignancy and autoimmunity.