ABSTRACT
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.
Subject(s)
Interferon Type I , Interferon-beta , Recombinant Proteins , Biological Assay , Chromatography, High Pressure Liquid , Drug Stability , Electrophoresis, Polyacrylamide Gel , Humans , Interferon beta-1a , Interferon beta-1bABSTRACT
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.
Subject(s)
Recombinant Proteins/standards , Tumor Necrosis Factor-alpha/standards , Amino Acid Sequence , Animals , Cell Survival/drug effects , Chromosome Deletion , Drug Stability , Genes , Mice , Mutation , Quality Control , Recombinant Proteins/pharmacology , Solutions , Temperature , Time Factors , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/pharmacologyABSTRACT
The antiviral activity of Escherichia coli-derived (Serine-17) human interferon-beta, formulated with human serum albumin, is stable for 2 years when lyophilized and stored under refrigeration. This product shows an Arrhenius line fit for the stability of its activity when tested at multiple isothermal temperatures (25-80 degrees C). In both isothermal and nonisothermal elevated temperature studies, increasing the level of human serum albumin in the formulation results in increased thermal stability.
Subject(s)
Interferon Type I/pharmacology , Interferon-beta , Recombinant Proteins/pharmacology , Vesicular stomatitis Indiana virus/drug effects , Cell Line , Drug Stability , Escherichia coli/genetics , Humans , Interferon Type I/genetics , Interferon beta-1a , Interferon beta-1b , ThermodynamicsABSTRACT
The relative activity of Flavobacterium whole cells on the enzymatic synthesis of epoxides from alpha,beta-chlorohydrins, -bromohydrins, and -iodohydrins is described.
