Effect of H1 Antagonists on the Progressive Growth of T Cell Lymphoma

The present investigation was undertaken to study the effect of H1 antihistaminic drugs: Chloropheniramine maleate (CPM) and Fexofenadine hydrochloride (Fx) on the progressive growth of a murine transplantable T cell lymphoma of spontaneous origin, designated as Dalton's Lymphoma (DL), and on the immune responses of the DL-bearing host. Administration of CPM and Fx to DL-bearing mice resulted in an augmentation of DL growth with an increase in the tumor cell count in Dl-bearing mice. Further, it was observed that there was a direct influence of the two drugs on DL cell proliferation. CPM and Fx augmented DL cell proliferation 1.4 and 1.5 folds, respectively. In vitro administration of CPM and Fx resulted in an increase in the count of splenocytes whereas that of thymocytes and bone marrow cells remained unchanged. However, splenocytes and thymocytes obtained from CPM and Fx administered mice showed an enhanced in vivo proliferation. CPM and Fx were found to enhance production of IL-1 by macrophages in the presence of LPS, which could be an additional indirect mode of the action of CPM and Fx on DL cell growth. These results may have clinical significance for patients-bearing lymphoma if undergoing treatment with CPM and Fx