Human Protein S (PS) Matched Antibody Pair

Name: Human Protein S (PS) Matched Antibody Pair
SKU: ABPR-L023
Rating: 5 (1 reviews)

Regulatory status: For research use only, not for use in diagnostic procedures.

COA

SDS

Datasheet

Summary

Sample

Plasma

Species Reactivity

Human

Detection Method

Sandwich ELISA

Intended Use

This antibody pair set comes with matched antibody pair to detect and quantify protein level of Human PROS1

Contents of Kit

1. Capture Antibody (yellow): 0.5 ml of affinity-purified polyclonal anti-Protein S antibody for coating plates.
2. Detecting Antibody (red): 0.5 ml of peroxidase conjugated polyclonal anti-Protein S antibody for detection of captured Protein S. Note: Reagents are sufficient for at least 5×96 well plates using recommended protocols. Antibodies are supplied in a 50% (v/v) glycerol solution for storage at –10 to -20°C. Keep vials tightly capped. Do not store in frost-free freezers.

Storage

-10 to -20°C

General Description

Protein S (PS) is a vitamin K-dependent glycoprotein produced in the liver, endothelium and megakaryocytes. The concentration of PS in plasma is ~25 μg/ml (~325 nM) where it acts as a cofactor in the anticoagulant activity of activated Protein C. A deficiency of Protein S (quantitative or qualitative) is a risk factor for vascular thrombosis. Protein S is expressed as a single chain molecule with a molecular weight of 77 kDa. The structure of PS is similar to many other vitamin-K dependent coagulation proteins, consisting of an N-terminal calcium binding domain of 10 γ-carboxyglutamic acid (gla) residues, followed by a thrombin-sensitive loop region and 4 EGF-like domains. The C-terminal domain does not contain the usual catalytic triad of a proenzyme, but seems instead to be involved in the binding of PS to C4b-binding protein (C4bp). Protein S binds to activated Protein C (APC) in the presence of calcium and negatively charged phospholipid surface to allow APC to proteolytically inactivate coagulation cofactors Va and VIIIa. Enzymatic regulation of PS cofactor activity is through cleavage of PS in the thrombin-sensitive loop region by thrombin or other enzymes, resulting in the loss of calcium binding properties and APC cofactor activity. Another regulatory mechanism is to reduce the availability of PS by the binding of PS to C4bp. In plasma, approximately 60% of Protein S circulates in non-covalent complex with C4bp, making it unavailable for APC cofactor activity. The binding of PS to C4bp may be important in localizing C4bp to damaged cell membranes where it may control activation of complement by the classical pathway.

Citations

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Documents

pdf COA

pdf SDS

pdf Datasheet

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References

Pulmonary deregulation of expression of miR-155 and two of its putative target genes; PROS1 and TP53INP1 associated with gold nanoparticles (AuNPs) administration in rat

INTERNATIONAL JOURNAL OF NANOMEDICINE

Authors: Ali, Ghada E.; Ibrahim, Marwa A.; El-Deeb, Ayman H.; Amer, Hassan; Zaki, Said M.

Abstract

Background: Gold nanoparticles (AuNPs) have been considered as an ideal candidate in various biomedical applications due to their ease of tailoring into different size, shape, and decorations with different functionalities. The current study was conducted to investigate the epigenetic alteration in the lung in response to AuNPs administration regarding microRNA-155 (miR-155) gene which can be involved in AuNP-induced lung pathogenesis. Methods: Thirty-two Wister rats were divided into two equal groups, control group and AuNPs treated group which received a single intravenous (IV) injection of plain spherical AuNPs (0.015 mg/kg body wt) with an average diameter size of 25 +/- 3 nm. Lung samples were collected from both the control and injected groups at one day, one week, one month and two months post-injection. The alteration of relative expression of miR-155 gene and two of its putative target genes; tumor protein 53 inducible nuclear protein 1 (TP53INP1) and protein S (PROS1) was investigated by real time PCR and protein S (PS) expression was analyzed by Western blotting technique. Results: The obtained results revealed that AuNPs administration significantly increases the expression level of miR-155 and reduce relative mRNA expression of TP53INP1 and PROS1 genes at one day post-injection. In contrast, a significant down-regulation of miR-155 level of expression concurrent with up-regulation of expression level of TP53INP1 and PROS1 genes were shown at one week, one month and two months post-injection. PS levels were mirrored to their PROS1 mRNA levels except for two month post-injection time point. Conclusions: These findings indicate epigenetic modulation in the lung in response to AuNPs administration regarding the miR-155 gene which can be involved in AuNP-induced lung pathogenesis.

Protein S Regulates Neural Stem Cell Quiescence and Neurogenesis

STEM CELLS

Authors: Zelentsova, Katya; Talmi, Ziv; Abboud-Jarrous, Ghada; Sapir, Tamar; Capucha, Tal; Nassar, Maria; Burstyn-Cohen, Tal

Abstract

Neurons are continuously produced in brains of adult mammalian organisms throughout life-a process tightly regulated to ensure a balanced homeostasis. In the adult brain, quiescent Neural Stem Cells (NSCs) residing in distinct niches engage in proliferation, to self-renew and to give rise to differentiated neurons and astrocytes. The mechanisms governing the intricate regulation of NSC quiescence and neuronal differentiation are not completely understood. Here, we report the expression of Protein S (PROS1) in adult NSCs, and show that genetic ablation of Pros1 in neural progenitors increased hippocampal NSC proliferation by 47%. We show that PROS1 regulates the balance of NSC quiescence and proliferation, also affecting daughter cell fate. We identified the PROS1-dependent downregulation of Notch1 signaling to correlate with NSC exit from quiescence. Notch1 and Hes5 mRNA levels were rescued by reintroducing Pros1 into NCS or by supplementation with purified PROS1, suggesting the regulation of Notch pathway by PROS1. Although Pros1-ablated NSCs show multilineage differentiation, we observed a 36% decrease in neurogenesis, coupled with a similar increase in astrogenesis, suggesting PROS1 is instructive for neurogenesis, and plays a role in fate determination, also seen in aged mice. Rescue experiments indicate PROS1 is secreted by NSCs and functions by a NSC-endogenous mechanism. Our study identifies a duple role for PROS1 in stem-cell quiescence and as a pro-neurogenic factor, and highlights a unique segregation of increased stem cell proliferation from enhanced neuronal differentiation, providing important insight into the regulation and control of NSC quiescence and differentiation.