ABSTRACT
The mitogenic selectivity of phytomitogens: phytohemaglutinin (PHA) and pokeweed mitogen (PWM) has been investigated, using, two mosaic lyphocyte cell lines from human donors: UGMC-0036 (45.X0/46.XX) and UGMC-0281 (46,XY/47,XXY) respectively, as a model to test karyotypic variation in terms of previously described heterogeneity of PHA and PWM responses of such cells onto the established T and B lymphocyte categories. A fixed peripheral blood leukocyte population was cultured by duplicated for each cell line (8 x10 a la 3 - 85 x 10 a la 2 cell/ml). Set of cultures were stimulated in paralell using, separately, PHA 0.25 ml/10 ml and PWM 0.1 ml/10 ml and incubated for 2.3.4.5. and 6 days. Mitotic Index calculations and Thymidine uptake (3H-TdR. 0.8 *Ci/ml) were used as a-measure of proliferative activity. Karyotypic analysis (n-20) were performed for each given experimental situation and pertinent metaphases recorded during maximum response periods to each polyclonal lymphocyte stimulant. Studies of the time course of thymidine incorporation in PHA as well as in PWM cultures, demostrate several differences in responce profiles elicited by them on both cell lines. To test the null hypothesis (H: p1-p2=0), which assumes no differences in the pairwise comparisons for karyotypic frequencies in the two cell lines stimulated separately, the test on the difference between the parameters of two binomial distribution was employed. Data analysis do not allowed, with the number of null hypothesis at the significance level set (D=0.05) in case of cell line UGMC-0036. However, values for cell line UGMC-0281 showed a significant heterogeneity in the 144 hrs. incubation period; so that, PHA-cultures gave a significant increase of 46.XY metaphases, whereas in PWM-cultures a significant increase for the 46.XXY clonus is demostrated. These observations suggest selective responses of T and B Lymphocytes, which may carry different sexual chromosome complement as result of nondisjuntion mitotic events during their clonal differentiation