<P> Blood proteins, also termed plasma proteins or serum proteins, are proteins present in blood plasma . They serve many different functions, including transport of lipids, hormones, vitamins and minerals in the circulatory system and the regulation of acellular activity and functioning of the immune system . Other blood proteins act as enzymes, complement components, protease inhibitors or kinin precursors . Contrary to popular belief, hemoglobin is not a blood protein, as it is carried within red blood cells, rather than in the blood serum . </P> <P> Serum albumin accounts for 55% of blood proteins, and is a major contributor to maintaining the osmotic pressure of plasma to assist in the transport of lipids and steroid hormones . Globulins make up 38% of blood proteins and transport ions, hormones, and lipids assisting in immune function . Fibrinogen comprises 7% of blood proteins; conversion of fibrinogen to insoluble fibrin is essential for blood clotting . The remainder of the plasma proteins (1%) are regulatory proteins, such as enzymes, proenzymes, and hormones . All blood proteins are synthesized in liver except for the gamma globulins . </P> <P> Separating serum proteins by electrophoresis is a valuable diagnostic tool as well as a way to monitor clinical progress . Current research regarding blood plasma proteins is centered on performing proteomics analyses of serum / plasma in the search for biomarkers . These efforts started with two - dimensional gel electrophoresis efforts in the 1970s and in more recent times this research has been performed using LC - tandem MS based proteomics . The normal laboratory value of serum total protein is around 7 g / dL . </P>

What plasma protein plays a large role in osmotic pressure regulation