RESUMO
Escherichia coli-derived (Serine 17) human interferon-beta (HuIFN-beta SER) was formulated with SDS and placed at multiple isothermal temperatures (-70 degrees C to 37 degrees C). Three stability-indicating test methods (bioassay, SDS-PAGE, RP-HPLC) were used to evaluate the long-term stability of this preparation. No change was observed when stored for nearly a year at either -70 degrees C or 4 degrees C. At the elevated temperatures, proteolytic cleavage, noncovalent oligomer formation, and loss of antiviral activity were observed. The absence of a carrier protein makes this stable IFN-beta frozen reference preparation useful as a standard in both biological assays and protein chemical methods of analysis.
Assuntos
Interferon Tipo I , Interferon beta , Proteínas Recombinantes , Bioensaio , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Eletroforese em Gel de Poliacrilamida , Humanos , Interferon beta-1a , Interferon beta-1bRESUMO
Escherichia coli-derived Tumour Necrosis Factor (TNF) was formulated in the absence of a protein-carrier, both as a solution and as a lyophilized preparation. By means of three stability-indicating test methods (bioassay, SDS-PAGE, IEF), the long-term stability of these TNF preparations was evaluated. Both preparations showed no change upon storage for 9 months at -70 degrees C and -20 degrees C. Depending upon the test method, different rates of change were detected at elevated temperature. The analysis presented will assist in the design of future TNF reference standards.