title: Novel purification method of human immunoglobulin by using a thermo-responsive protein A.
abstract: We attempted to evaluate a novel purification method of immunoglobulins (IgGs) by using a mutant type of protein A. Although this mutant protein A binds to IgGs at 5°C, the IgGs are released at 40°C; hence, it was designated as thermo-responsive protein A (TRPA). We aimed to purify IgG1 from the culture supernatant of CHO cells producing AE6F4 human monoclonal IgG1. AE6F4 IgG1 was purified using only a TRPA-filled column and by modifying the temperature, without any exposure to acidic conditions. Furthermore, the purified AE6F4 IgG1 maintained the inherent binding affinity to antigen, while this property was lost in AE6F4 IgG1 purified using a conventional protein A (CPA) column possibly because of product aggregation and fragmentation. These data suggest that IgG is sensitive to acid treatment; however, it can be highly purified with retention of high affinity by using a TRPA column. Further, this purification method can be used on an industrial scale for the purification of antibody drugs.
authors.affiliation: New Product Development Department, Bioprocess Division, Asahi Kasei Medical Co., Ltd., 2-1 Samejima, Fuji-City, Shizuoka 416-8501, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Koguma
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Yamashita
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sato
authors.forename: Kazuo
authors.initials: K
authors.lastname: Okuyama
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Katakura
mesh_terms: D000818:Animals; D016466:CHO Cells; D002850:Chromatography, Gel / Q000379:methods*; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D007074:Immunoglobulin G / Q000302:isolation & purification*; D013205:Staphylococcal Protein A / Q000737:chemistry*; D013696:Temperature
chemical_list: D007074:Immunoglobulin G; D013205:Staphylococcal Protein A
keywords: Protein A; Purification of IgG; Thermo-responsive protein A