Purification of A1PI from Human Plasma-An Improved Process to AchieveTherapeutic Grade Purity

摘要

Alpha-1-proteinase inhibitor (A1PI) also known as α-anti trypsin (AAT) is a member of serine protease inhibitors super family present in human plasma. A1PI is the only known inhibitor of elastase but also inhibits trypsin and chymotrypsin. A1PI is a molecule with lot of therapeutic importance and is widely used in the treatment of emphysema or chronic obstructive pulmonary disease (COPD). There are many methods detailed in scientific articles and patents to purify A1PI but the current research describes a simple three step chromatography procedure to fractionate A1PI directly from human plasma. The current purification process starts from human plasma unlike most of the existing methods where Cohn fraction IV-1 paste is the starting material. This method excludes the use of more methods like Cohn ethanol fractionation, precipitation or affinity capture. The A1PI purified by this scheme is characterized and found to be a single chain glycoprotein with a molecular weight of 52 KDa with increased purity. As the process is devoid of precipitation and affinity steps, this scheme is easily scalable, economical to adapt for manufacturing A1PI with good yields of 0.6-0.7 gm of A1PI/L of plasma.