Recombinant Human Protein S/PROS1, CF

Recombinant Human Protein S/PROS1, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: Protein S/PROS1

Anticoagulant Protein S (PROS1) is a 71 kDa plasma vitamin K-dependent glycoprotein characterized by the presence of the post-translational modification of specific glutamic acid residues to gamma-carboxyglutamic acid (Gla) in the N-terminal region. In addition to the N-terminal Gla domain, mature PROS1 contains a thrombin‑sensitive thumb loop, four tandem EGF-like domains and a C-terminal sex hormone-binding globulin (SHBG) domain composed of two Laminin G (LG) domains (1). Human PROS1 shares 80% amino acid sequence identity with mouse PROS1. Hundreds of mutations have been reported throughout all the domains of the protein, typically resulting in PROS1 deficiency and an increase in the risk of thrombophilia (2, 3). PROS1 is expressed in many cell types supporting its reported involvement in multiple biological processes that include coagulation, apoptosis, cancer development and progression, and the innate immune response (4-9). PROS1 exists in plasma both in complex with C4b-binding protein (C4BP) (60%) and in a free form (40%). Both forms of PROS1 have anti-coagulant activity either directly through inhibition of Factor X systems and prothrombinase while in complex with C4BP (5, 10) or in its well-established role as a cofactor of activated protein C (APC) inactivation of procoagulants FVa and FVIIIa (4). The free form of PROS1 is also a ligand for a subfamily of receptor tyrosine kinases known as TAMs, which is composed of TYRO3, AXL, and MERTK (11). PROS1 binds these tyrosine kinase receptors through its LG domains to activate downstream signaling pathways involved in tumor development and progression (7, 8, 11, 12).