Blood plasma proteins

Blood plasma proteins represent a heterogeneous group of proteins suspended in the blood plasma that perform vital physiological functions, including the maintenance of oncotic pressure, pH buffering, and the transport of various substances such as hormones, vitamins, and drugs (StatPearls: Physiology, Plasma Proteins, 2023). The most abundant of these is albumin, followed by globulins (alpha, beta, and gamma) and fibrinogen (NCBI: Plasma Proteins, 1996). These proteins are essential for the immune system's function and the coagulation cascade, preventing excessive bleeding after injury. In clinical pharmacology, plasma proteins are a major determinant of drug pharmacokinetics; the degree of plasma protein binding (PPB) dictates the fraction of a drug available to reach its site of action and undergo metabolism or excretion (Journal of Pharmaceutical Sciences: Plasma Protein Binding, 2010). Pathological conditions like liver disease or nephrotic syndrome can significantly alter plasma protein concentrations, leading to impaired transport or altered drug sensitivity (Mayo Clinic: Hypoalbuminemia, 2023). While the collective group is not a single therapeutic target, specific proteins within the plasma are frequently targeted by drugs or administered as replacement therapies to treat conditions like hemophilia or immunodeficiency.

Other names

Plasma proteinsSerum proteinsCirculating proteins

Non-specific reversible binding; Enzymatic inhibition of coagulation factors; Immune modulation via immunoglobulin binding