Spleen white pulp morphology as an indicator of the immunological state in DBA/2 mice bearing mastocytoma.

The morphology of the spleen white pulp in DBA/2 mice bearing the chemically induced mastocytoma, P-815-X2, was evaluated by using the standardized reporting system previously introduced to describe the spleen morphology in relation to immunological functions. Special emphasis was placed on the assessment of the T- and B-lymphocytes, the appropriate functions of which have previously been proposed to be affected by the tumor concerned. When compared with the control mice, both the central perarterial lymphoid sheaths (C-PALS) and peripheral periarterial lymphoid sheaths (P-PALS) T- and B-cell areas, respectively, were seen to be altered in a way suggesting derangement in the function of both these lymphocyte populations, almost exclusively in mastocytoma-bearing mice. The present results, thus, confirm the observations made earlier on the immunosuppressive potentialities of mastocytoma in DBA/2 mice, and the recording system used seems to be a suitable one to be applied in the evaluation of the morphologic manifestations of these immunological functions.