FCRN-B2M Heterodimer Protein, Human (HEK293, His)

The FCGRT protein is a cell surface receptor that conveys passive humoral immunity through the selective uptake of monomeric IgG in milk. It binds IgG at the intestinal epithelium and forms an FcRn-IgG complex that is transcytosed across the epithelium, releasing IgG into the blood or tissue. FCRN-B2M Heterodimer Protein, Human (HEK293, His) is a recombinant protein dimer complex containing human-derived FCRN-B2M Heterodimer protein, expressed by HEK293 , with C-His labeled tag. FCRN-B2M Heterodimer Protein, Human (HEK293, His), has molecular weight of ~35 & 12 kDa, respectively.

FCGRT, a crucial cell surface receptor, facilitates the transfer of passive humoral immunity from the mother to the newborn by binding to the Fc region of monomeric immunoglobulin gamma and selectively mediating its uptake from milk. The process involves IgG binding at the apical surface of the intestinal epithelium, forming FcRn-IgG complexes that transcytose across the intestinal epithelium, releasing IgG into blood or tissue fluids. Beyond infancy, FCGRT plays a pivotal role in effective humoral immunity by recycling IgG and prolonging its half-life in the circulation. Mechanistically, the binding of monomeric IgG to FCGRT in acidic endosomes of endothelial and hematopoietic cells facilitates the recycling of IgG to the cell surface, subsequently releasing it into circulation. Additionally, FCGRT regulates the homeostasis of albumin/ALB, the other most abundant circulating protein, further underscoring its essential role in immune and protein homeostasis. In the context of microbial infection, FCGRT acts as an uncoating receptor for various echoviruses, including Echovirus 5, 6, 7, 9, 11, 13, 25, and 29.

Measured by its ability to bind human IgG1 in a functional ELISA.

Human

HEK293

C-His

P55899 (A24-S297)&P61769 (I21-M119)

2217  [NCBI]&567

Approximately 33-40 kDa (FCGRT) & 10-14 kDa (B2M), based on SDS-PAGE under reducing conditions, due to the glycosylation.

≥ 95%, as determined by reducing SDS-PAGE.

Lyophilized powder.

Lyophilized from a 0.2 μm filtered solution of PBS, pH 7.4. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween 80 are added as protectants before lyophilization.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O.

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.

• [1]. /biology-dictionary/caco-2-cell.html  [Content Brief]