Sequential monitoring of peripheral blood lymphocyte subsets in rats.

The methodology of enumeration of T cell subsets in humans is well established and has widespread clinical application. Sequential monitoring of lymphocyte subsets in small animals requires a consistent and reliable methodology for staining and enumerating lymphocyte populations. The optimal conditions for enumerating subclasses of rat peripheral blood lymphocytes with the Spectrum III flow cytometer are described. The sources of biological variation and technical error that were considered in optimizing the techniques and the limitations in applying them are discussed.