Validation of an eight parameter immunophenotyping panel in adult canines for assessment of immunotoxicity

Analysis of peripheral blood leukocyte populations by flow cytometry in adult beagles is a critical component of immunotoxicity assessment in regulated pre-clinical toxicology studies. In this study, data is presented utilizing a single panel, six-color method to simultaneously enumerate absolute cell counts and determine the relative percentage of leukocytes. A GLP validation was performed to determine intra- and inter-assay variance, inter-instrument variance, and pre- and post-fixation stability for the target populations. The results demonstrated all samples met acceptance criteria, CV values less than 25%, for all precision and stability intervals assessed. The intra and inter-assay data demonstrated the single panel method generated acceptable precision. Furthermore, stability results indicated whole blood samples and processed samples may be stored without a statistically significant difference in the data compared to samples immediately processed and analyzed after blood collection. This assay will provide researchers a more precise and efficient tool to evaluate the immunotoxic effects of a test article on canine peripheral blood leukocytes during pre-clinical drug testing.