Induction of alkaline phosphatase activity in murine spleen cells treated with various mitogens.

The correlation between murine lymphocytes blastoid transformation and alkaline phosphatase (AL-P) activity was examined. When murine spleen cells were stimulated with lipopolysaccharide, a B cell mitogen, for 48 h, the AL-P activity was induced in a dose dependent manner. Similarly, stimulation of the spleen cells with Concanavalin A (Con A), a T cell mitogen, induced the AL-P activity. However, when the thymocytes were treated with Con A, only the [3H]dThd uptake was increased. Other B cell mitogens, such as lipid A and fungal B cell mitogens, and T cell mitogen, Pusum sativum agglutinin (PSA) also induced the AL-P activity of spleen cells. Kinetics of [3H]dThd uptake and induction of AL-P was similar. Correlation coefficients between [3H]dThd uptake and AL-P activity were r = 0.98789, p less than 0.01 for LPS, r = 0.99530, p less than 0.01 for lipid A and r = 0.62595, p less than 0.001 for the fungal B cell mitogens. The AL-P activity of the spleen cell was also induced by treatment with Con A sup, which was a supernatant fluid prepared by spleen cell cultured with Con A for 48 h, containing various lymphokines. These findings suggest that the AL-P activity was induced in the case of B lymphocyte blast transformation when stimulated directly with B cell mitogen or indirectly via lymphokines with T cell mitogen. Measurement of the AL-P activity would be a useful method to assay murine blastoid lymphocytes.