Source

Human CD16b (NA1) (SPR verified) (H-FRIIIB/CD16) is expressed from human HEK293 cells. It contains AA Gly 17 - Ser 200 (Accession # AAA35881.1).\rThe NA1 form of the CD16b differ with the NA2 form of CD16b in AA36, 65, 82, and 106. The NA1 form carries R3

Molecular Characterization

This protein carries a polyhistidine tag at the C-terminus.

Endotoxin

Less than 0.01 EU/mg by the LAL method.

Purity

>95% as determined by SDS-PAGE.

Bioactivity

ELISA ；

BIACORE (With our Research Grade Biosimilar Antibody products);

Formulation

Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. Normally trehalose is added as protectant before lyophilization.

Reconstitution

Please see Certificate of Analysis for specific instructions.

For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.

Storage

For long term storage, the product should be stored at lyophilized state at -20°C or lower.

Please avoid repeated freeze-thaw cycles.

No activity loss was observed after storage at:

4-8°C for 12 months in lyophilized state;

-70°C for 3 months under sterile conditions after reconstitution.

Background

CD16 is a low affinity Fc receptor, and has been identified as Fc receptors FcγRIIIa (CD16a) and FcγRIIIb (CD16b). These receptors bind to the Fc portion of IgG antibodies. CD16 encoded by two different highly homologous genes in a cell type-specific manner.CD16 is found on the surface of natural killer cells, neutrophil polymorphonuclear leukocytes, monocytes and macrophages.\rCD16B is also kown as FCGR3B and FCG3B, is expressed specifically by polymorphonuclear leukocytes (neutrophils) and stimulated eosinophils. CD16B is the low affinity receptor for the Fc region of immunoglobulins gamma. FCGR3B binds complexed or aggregated IgG and also monomeric IgG. Contrary to III-A, FCG3B is not capable to mediate antibody-dependent cytotoxicity and phagocytosis. CD16B may serve as a trap for immune complexes in the peripheral circulation which does not activate neutrophils.

Reference

(1) Ravetch J.V., et al., 1989, J. Exp. Med. 170:481-497.

(2) Gessner J.E., et al., 1995, J. Biol. Chem. 270:1350-1361.

(3) Bux J., et al., 1997, Blood 89:1027-1034.