EFFECT OF PH, HYDROGEN-PEROXIDE AND TEMPERATURE ON THE STABILITY OF HUMAN MONOCLONAL-ANTIBODY

The stability of human monoclonal antibody (C23), which is being devel oped as a passive immunotherapeutic agent against human cytomegaloviru s, was investigated. C23 (about 2 mg ml(-1)) was incubated under steri le conditions for 14 days in buffers with different pH values (ranging from 4-10), in hydrogen peroxide solutions with different concentrati ons (0.01% or 0.1%), and in saline at 8 degrees C or 37 degrees C. Sam ples were collected on days 0, 3, 7 and 14, and various physicochemica l or biological methods were used to determine the changes in C23. The se methods included turbidity (absorbance at 408 nm and transmittance at 580 nm), pH, size-exclusion high performance liquid chromatography (HPLC), hydroxyapatite HPLC, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing, matrix-assisted laser desorpti on ionization time-of-flight mass spectrometry and virus neutralizatio n assay. Using these methods, the possible degradation processes of C2 3 were initially characterized. Deamidation, oxidation, fragmentation, covalent cross-links and aggregation were observed as major degradati on routes. These results gave useful information for the manufacturing process and quality control of C23.