Human Serum and its Important Role in Research

April 15, 2019

Human serum is one of the most important tools in today’s laboratories, and for good reason – human serum allows scientists to grow human cells, test the efficacy of drugs, gain a deeper understanding of the immune system, and perform innovative research. While processing human serum for use in research is complex, it yields a product that provides reliable, repeatable results in the laboratory.

Human blood contains more than 4,000 components, each with a different purpose. The major components of whole blood are red blood cells, white blood cells, plasma, and platelets. Human blood is about 55 percent plasma and 45 percent cells. Red blood cells carry oxygen and white blood cells fight infection. Plasma is the watery, clear yellow-tinted fluid that holds the cells and platelets, along with sugars, lipids, vitamins, minerals, hormones, enzymes, antibodies, other proteins, and blood clotting factors.

After gently drawing blood from donors to avoid damaging the blood cells, laboratory professionals use a centrifuge to separate the cells from the plasma. Laboratories can further separate serum from the plasma. Human plasma and serum are similar, except for the presence of clotting factors. These clotting factors, especially fibrinogen, are essential for clotting to take place. When laboratories separate human serum and plasma from whole blood, the plasma retains the fibrinogen while the serum does not. This means human serum does not clot, or coagulate, because it does not contain the clotting factor fibrogen.

While human serum does not contain fibrinogen, it does contain hormones, minerals, proteins and carbon dioxide. Albumin is an important protein in human serum, as it carries steroids, fatty acids, and thyroid hormones in the blood. Human serum is also an important source of electrolytes.

Human serum allows substances to stick to the molecules within the serum, effectively binding the substance into the blood, which allows the serum to transport fatty acids, thyroid hormones and other substances. Because it works as a circulating carrier, drug manufacturers design protein-binding medications that bind to albumin

Drug manufacturers take advantage of albumin’s function as a carrier by designing protein-binding medications that bind to albumin – the albumin then carries the medications through the bloodstream to the target tissue or organ. The albumin in human serum binds to the curable substances in antibiotics, for example, which allows the antibiotics to be carried throughout the body.

Uses for Human Serum

Researchers use human serum where animal serum is not an appropriate substitute, such as DNA research, cancer therapy studies, and more. Scientists frequently use human serum as an added supplement to culture media, as many human cells require human serum rather than animal serum to grow satisfactorily.

Human serum provides superior results when culturing many types of human cell, but especially for cells associated with the human immune system. Researchers use human serum to supplement lymphocyte culture media, which supports the growth of the human lymphocytes and dendritic cells that play an important role in immunity. They use human serum in immunohistochemical staining procedures, a process that identifies foreign antigens that trigger an immune response. Scientists also use human serum in human leukocyte antigen (HLA) tissue-typing applications that test for compatibility between donor and recipient in organ transplants.

Human off-the-clot serum is ideal for metabolic studies. To collect human off-the-clot serum, laboratories allow the whole blood to coagulate naturally and without exposure to anticoagulants after collection. Next, the laboratory uses a centrifuge to separate the serum from its cellular components before allowing the serum to undergo a secondary clotting. Allowing the serum to clot again ensures complete removal of any remaining clotting components. Laboratories then centrifuge the specimen again before drawing off the remaining serum and packaging it according to researchers’ requirements.

Human AB serum is essential in the investigation of cell therapy applications, transplantation and tissue engineering. Laboratories collect human AB serum from donors who have type AB blood, which lacks the antibodies against blood type A and B antigens.

Human complement serum is for in vitro research only and biocompatibility experiments. Human complement serum is a complex mixture of serum proteins activated when antibodies in an immune subject interacts with corresponding antigens.

Human serum allows scientists to perform innovative research in the laboratories and to discover new drugs, therapies and procedures to improve human health. For more information about human serum, contact BioChemed Services.