Immunosupressive activity of the basic protein from tumor tissue.

The basic protein prepared from AH-130 ascites hepatoma cells was tested for its effect on the cell-mediated immune response of Donryu strain rats. The basic protein suppressed the response of peripheral and lymph node lymphocytes to phytohemagglutinin and lymphocyte trapping in the antigen-draining lymph node. These results indicated that the basic protein from tumor tissue possibly had an immunosuppressive activity and affected inadequately the cell-mediated immune response as usually observed in tumor-bearing hosts.