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How Plasma Donation Works

Plasma Therapies

Plasma protein therapies (PPTs) are considered biologic medicines, which means that unlike many of the common drugs we take which have been manufactured through chemical ingredients, these are protein-based therapies developed from human genes.

PPTs are typically given through an infusion or injection. RH-negative pregnant women, for example, receive a type of PPT called hyperimmune globulin therapy. Rhogam is a product made with human plasma and given to both mother and newborn to prevent fetal complications; hyperimmune globulin therapy is also used to treat patients with infectious diseases including rabies, tetanus and liver conditions such as hepatitis and cirrhosis, as well as those who undergo organ transplant.

Human serum albumin therapy, also a form of PPT, is used to treat burn victims as well as shock and trauma patients; it's also a relied-upon therapy in the emergency room and during major surgeries.

Plasma proteins are also used as therapy in genetic bleeding and clotting disorders, including Von Willebrand disease, antithrombin disorders and hemophilia. It takes a lot of plasma to make a plasma protein therapy product, and as many as 1,200 plasma donations can be required to treat just one hemophiliac patient for one year [source: DonatingPlasma].

Collected plasma is processed before it's turned into a plasma product; it can take up to 9 months between the time the plasma was donated and the time it's used in a therapeutic product [source: Baxter]. After being screened for known infectious diseases (including HIV, hepatitis and other transmissible diseases), the plasma first goes through something called the blood plasma fractionation process.

Fractionation was developed during World War II by biochemist Edwin Cohn, who pioneered a method for separating the plasma protein serum albumin from whole blood, a life-saving alternative therapy for those who were wounded during battle and needed plasma. Today's technologies for separating blood components include centrifugation and filtration which spins blood to separate the liquid and solid components, thermal and chemical inactivation procedures, ultrafiltration, diafiltration, nanofiltration and chromatography. Since the 1980s, some plasma proteins have been successfully cloned, including factor VIII.