Inosiplex, a stimulating agent for normal human T cells and human leukocytes.

The influence of inosiplex upon various in vitro leucocyte assays was studied in normal individuals. It was found that the drug increases the response of bidirectional and unidirectional mixed lymphocyte cultures at concentrations of 200, 300, and 500 microgram/ml. It also significantly increases the percentage of active T rosettes (concentration range: 50 to 500 microgram/ml) and the percentage of autologous red cell T rosettes (concentration: 100 microgram/ml). In contrast, inosiplex did not modify the percentage of total T rosettes and EAC rosettes. Inosiplex increases the number of nonadherent leucocytes in the leucocyte adherence inhibition test at a concentration range between 100 and 300 microgram/ml. Finally, inosiplex also increases the percentage of monocytes phagocytizing yeast at a concentration between 50 and 500 microgram/ml. These data indicate that inosiplex enhances the function of normal human T cells, monocytes, and possibly neutrophils. Therefore inosiplex appears to have immunostimulant properties.