Novel approach to activity evaluation for release-active forms of anti-interferon-gamma antibodies based on enzyme-linked immunoassay.

Selection of a suitable assay to measure the activity of drug agents based on release-active forms of anti-interferon-gamma antibodies (RA forms of Abs) is an important step forward in the investigation of such agents. In this study, the enzyme-linked immunosorbent assay was utilized to examine the effect of RA forms of Abs specific for human interferon gamma on the interaction between monoclonal anti-interferon gamma antibodies and recombinant human interferon gamma. The experimental data and the results obtained by using relevant mathematical analysis showed that such RA forms of Abs are able to modulate the monoclonal antibody interaction with both soluble and immobilized (to the assay plate well) interferon gamma. These data demonstrated the importance of using relatively low concentrations of both soluble and plate-immobilized interferon gamma to detect the effects of RA forms of Abs to interferon gamma on the binding of monoclonal antibodies to interferon gamma. It has been suggested that the observed influence of RA forms of Abs on 'antibody-antigen' interaction could be used to detect and analyze the activity of drugs containing RA forms of Abs.

Application of a heterogeneous immunoassay for the quality control testing of release-active forms of diclofenac.

We report on a specially designed diclofenac-ELISA for the determination of diclofenac in the presence of release-active forms of diclofenac in lactose dissolved in water solutions according to a predefined schedule in single-blind experiments. In accordance with the objective of this project, a number of experiments were conducted to determine the optimal ELISA conditions for detecting potential modulatory effects of release-active forms of diclofenac depending on their ability to affect the binding of diclofenac to anti-diclofenac antibodies. As a feature, the diclofenac antibodies were previously incubated with manufactured pharmaceutical samples containing release-active forms of diclofenac or placebo. For comparison of the sample types, measured in ELISA optical densities were chosen. For statistic analysis, Student's two-sample t-test and single-factor ANOVA were applied. The extremely low concentrations of diclofenac of 0.01, 0.05 and 0.1 ng mL(-1) seem most appropriate for routine assay performance. The source of diclofenac used for standard solution preparation is not important but it could be important as the source of diclofenac for release active form of diclofenac preparation. As an outcome, the ELISA appeared to be suitable for the detection of the modifying effects of release-active forms of diclofenac toward the pharmaceutical substance in vitro.