Immunologic differentiation between E. coli and CHO cell-derived recombinant and natural human beta-interferons.
The products of the human IFN-beta gene expressed in E. coli, Chinese hamster ovary (CHO) cells, and human fibroblasts appear similar when purified on a monoclonal antibody column and analyzed by reverse-phase HPLC, indicating little difference in their hydrophobic nature. SDS-PAGE differentiates E. coli-rHuIFN-beta ser (Mr = 17,000) from CHO-rHuIFN-beta and HuIFN-beta (Mr = 23,000), with glycosylation accounting for 26% of the apparent m.w. of the latter two proteins. CHO-rHuIFN-beta is preferentially neutralized by mouse monoclonal and monospecific rabbit polyclonal anti-HuIFN-beta antibodies, whereas E. coli-rHuIFN-beta ser is preferentially neutralized by goat polyclonal anti-E. coli-rHuIFN-beta antibodies. Adsorption measurements by a sensitive radioimmunoassay indicate that the binding of the three proteins to anti-HuIFN-beta antibodies is similar. The results show that all three molecules can be differentiated by the heteroclitic cross-reactivities of anti-HuIFN-beta and anti-E. coli-rHuIFN-beta antibodies to the antigens.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001666:Binding Sites, Antibody; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D006224:Cricetinae; D003412:Cricetulus; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000276:immunology*; D006801:Humans; D007163:Immunosorbent Techniques; D007370:Interferon Type I / Q000145:classification* / Q000276:immunology / Q000302:isolation & purification; D051379:Mice; D009500:Neutralization Tests; D011817:Rabbits; D011863:Radioimmunoassay; D011995:Recombination, Genetic
D000911:Antibodies, Monoclonal; D007370:Interferon Type I