Protein S activity

General Information

For research Pattern Taking It will happen:

• In the regions: Thursday  
• In Tbilisi: on Thursday or/And on Friday (Of the day first in half)

Samples Send Will be implemented On Friday, Of the day second Halfway! For this,  Central Sample in the laboratory Should To be sent on Friday  It is 12:00.till

Protein S is a vitamin K-dependent glycoprotein present in platelets and synthesized by liver and endothelial cells.

Protein S acts as a natural anticoagulant. It is a cofactor of -activated protein C (APC), which ensures the inactivation of coagulation factors Vα and VIIIα. In addition, protein S has anticoagulant activity independent of activated protein C, which prevents the formation of prothrombin complexes.

Congenital protein S deficiency is an autosomal dominant disorder. It occurs in 2-6% of patients with deep vein thrombosis. In these patients, the risk of spontaneous abortion, pregnancy complications and arterial thrombosis is much higher.

Three variants of protein S deficiency have been described: according to total and free protein S antigen levels and plasma protein S activity. Variants I and III are more typical than II - dysfunctional protein S deficiency.

Homozygous protein S deficiency is rare, may present with disseminated intravascular coagulation in infants, and is characterized by complete absence of protein S.

The exact causes of acquired protein S deficiency are unknown. It can develop in the background of any risk factor for thrombosis and occurs more often than congenital forms. Acquired protein S deficiency may be due to: vitamin K deficiency, anticoagulation therapy, liver disease, thrombotic thrombocytopenic purpura, pregnancy, estrogen therapy, nephritic syndrome, sickle cell anemia, and others.