FCGRT Protein, Human (GST)

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. FCGRT Protein, Human (GST) is the recombinant human-derived FCGRT protein, expressed by E. coli , with N-GST labeled tag.

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.

Human

E. coli

N-GST

P55899 (A24-S297)

2217  [NCBI]

Extracellular Domain

AESHLSLLYHLTAVSSPAPGTPAFWVSGWLGPQQYLSYNSLRGEAEPCGAWVWENQVSWYWEKETTDLRIKEKLFLEAFKALGGKGPYTLQGLLGCELGPDNTSVPTAKFALNGEEFMNFDLKQGTWGGDWPEALAISQRWQQQDKAANKELTFLLFSCPHRLREHLERGRGNLEWKEPPSMRLKARPSSPGFSVLTCSAFSFYPPELQLRFLRNGLAAGTGQGDFGPNSDGSFHASSSLTVKSGDEHHYCCIVQHAGLAQPLRVELESPAKSS

Approximately 57.4 kDa

≥ 90%, as determined by reducing SDS-PAGE.

Lyophilized powder.

Lyophilized from a 0.22 μm filtered solution of PBS, 6% trehalose, pH 7.4.

<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.