Abstract
BCG, protein-bound polysaccharide Kureha (PS-K) and levamisole which have been used in tumor immunotherapy were studied for the effect on the rejection of male skin grafts by female mice. The graft rejection was significantly accelerated by one s.c. injection of BCG (5×105 microorganisms/mouse) into recipients on the day of transplantation. PS-K injected 250 mg/kg s.c. or i.p. once every other day from the day of transplantation significantly stimulated the graft rejection. Oral administration of 1000 mg/kg PS-K by the same schedule was also effective. Levamisole 20 mg/kg injected s.c. once on the day of transplantation was without any effect.
From these results it is concluded that PS-K has an immunostimulant action similar to that of BCG. This property may be important to the antineoplastic activity of PS-K.
