We have established reference values of peripheral blood lymphocyte subsets in healthy female Wistar rats under highly standardized conditions. Using monoclonal antibodies and flow cytometry, T lymphocytes (OX19+), B lymphocytes (OX6+ and anti-Ig+), T-helper/inducer (W3/25+), and T-suppressor/cytotoxic subsets (OX8+) were determined, from week 11 to week 21 after birth. The mean percentages of T and B lymphocytes with respect to total lymphocytes were 78.5% and 18%, respectively; the mean percentages of T-helper/inducer and T-suppressor/cytotoxic cells in relation to T lymphocytes were 59% and 25%, respectively (n = 48). No difference in total leukocyte count, differential leukocyte analysis, or lymphocyte subsets was observed during the 10 weeks the rats were studied under standard housing conditions. Therefore, the period considered seems the most appropriate in which to carry out experiments that could involve lymphocyte subset disturbances.
