THE INFLUENCE OF IMUVERT, A BIOLOGICAL RESPONSE MODIFIER, ON THE GROWTH AND GANGLIOSIDE COMPOSITION OF MURINE NEURAL TUMORS

ImuVert is a biological response modifier (BRM) that has anti-tumor ef fects in humans and rats. The influence of ImuVert on the ganglioside composition of two experimental brain tumors, ependymoblastoma and CT- 2A, was studied in C57BL/6J mice. Gangliosides are expressed on plasma membranes and can serve as markers to distinguish neural cells from n onneural cells in mouse brain tumors. N-acetylneuraminic (NeuAc) is th e predominant sialic acid in mouse neural cells, whereas N-glycolylneu raminic (NeuGc) is a major sialic acid in nonneural cells, e.g., macro phages and lymphocytes. ImuVert treatment increased the NeuGc ganglios ide concentration in the ependymoblastoma, but had no effect on the si alic acid concentration in the CT-2A brain tumor. ImuVert also had a s light inhibitory effect on the growth of both brain tumors.