Purification of α₁ Proteinase Inhibitor from Human Plasma Fraction IV‐1 by Ion Exchange Chromatography

Abstract

The method described is an effective way of preparing large quantities of alpha 1 PI from fractionated plasma.

Blood protein purification and simultaneous removal of nonenveloped viruses using tangential-flow preparative electrophoresis

“…The separation membrane prevented CPV from migrating into the product stream and at least a 4 log reduction was demonstrated with PCR and infectivity assays ( Table 1). The high yield and 10-fold reduction of albumin in Gradiflow a-1-antitrypsin exceeds current multistep purification schemes that achieve 15-63% yields [22,23] with 60-90% purity, after as many as seven separate purification steps. Similar to commercial IgG processes, Cohn precipitation (Cohn IV-I) and PEG precipitation affect the yield and quality of the commercial a-1-antitrypsin product.…”

“…Immunoglobulins are traditionally isolated using Cohn ethanol precipitation [20] followed by ion-exchange chromatography polishing steps. a-1-Antitrypsin [21][22][23] is an acid glycoprotein of 53 kDa with a pI of 4.8, and is widely used in the treatment of hereditary emphysema. Conventional purification…”

Yield improvement for manufacture of α1‐proteinase inhibitor

“…Alpha1-PI activity was measured as described previously [5]. Azocaseinolysis was assayed at 5 ° C and pH 8·1 or 9·3 by standard procedure [6]; linear kinetics were obtained during the time course of the assay.…”

“…In these experiments, the IV-1 paste samples were completely dissolved in all cases, thus providing a normalized IV-1 paste-weight basis upon which to compare yields of active α 1 -PI. α 1 -PI constitutes approximately 10% of the total protein present in IV-1 suspension [5].…”

“…Unfortunately, approximately 50% of the original activity of α 1 ‐PI is lost during the generation and dissolution of IV‐1 paste, even though most of the total α 1 ‐PI protein (i.e. antigen) is recovered [5]. This report describes results of a study aimed at improving the yield of active α 1 ‐PI and presents biochemical data supporting a rationale for the observed yield improvement.…”