From Plasma to Medicines by Fractionation
Plasma is the yellow liquid suspending the cell components (red and white cells, platelets) in blood. The plasma portion is about 50% of the total blood volume and contains and wide range of proteins essential to life. Each protein has a specific purpose for the human well-being. For example, some of the proteins are essential for the blood to coagulate when needed, others carry certain molecules from one part of the body to another, and some like the antibodies are there to fight against infectious agents as bacteria and viruses entering the blood-stream. If a person lacks or has an inactive form of a certain protein due to an inborn defect or other condition, it may lead to a disease which can even be life-threatening. It is often possible to replace the lacking plasma protein with the proteins from other human beings and treat the patient. Therefore plasma is an important source of proteins which can be used to treat specific and many times severe diseases.
Fractionation is the name used for the method to separate and purify each of the important proteins in plasma into concentrates that can be given as injectable medicines. The method to fractionate plasma has been in use for many decades, and the aim has always been to utilize the valuable plasma source to produce a wide range of plasma medicines that patients may need. Today, fractionation is a highly developed bioprocess that can be carried out from small scale (a couple of donations) to industrial pharmaceutical production where plasma from thousands of donations are combined.
Plasma can be collected in two major ways. The more traditional way is to separate the plasma from the cells (red, white, platelets) by centrifugation from a whole blood donation. This type of plasma is called recovered plasma. The other way is to collect plasma by plasmapheresis. This is a method whereby the donor is connected to a machine where the plasma is separated from the cells and the cells are directly returned to the donor and only the plasma is used. Plasma collected by plasmapheresis is often called source plasma. Both types of plasma are used for the fractionation of plasma into medicines.
What are plasma-derived medicines and when are they needed?
The medicines produced from plasma can be referred to as plasma-derived medicinal products. The proteins in plasma are needed for human well-being, and lack of them in an individual may lead to severe and even life-threatening conditions. Many of the plasma medicines are therefore included in the WHO Model List of Essential Medicines. There are many types of diseases and conditions that can be treated with the plasma derived medicinal products:
For further information please click here to access the article “Evidence-based clinical indications of plasma products and future prospects”, published 21 December 2017 in Annals of Blood.