[Analysis of human sera obtained from lung cancer patients by two-dimensional electrophoresis after schizophyllan (SPG) treatment].

Schizophyllan (SPG) was administered to 13 lung cancer patients (i.m. 20mg X 2/week) for 3 weeks without chemo or irradiation therapies, and serum proteins were analyzed by two-dimensional electrophoresis (TDE). Additionally, immunosuppressive acidic protein (IAP) was quantitatively determined by single radial immunodiffusion (SRID). By TDE analysis, human serum proteins were separated into more than 100 spots, and about 14 spots were found to show quantitative changes in cancer patients. Quantitative examination was therefore conducted on changes of 8 components among these spots, including alpha 1-acidic glycoprotein (alpha 1 AG), acidic alpha 2-macroglobulin (acidic alpha 2 M), haptoglobin (Hp) and IAP. The protein which showed the most marked decrease in cancer patients, located between transferrin and IgG on the above TDE patterns, was ascertained to have a molecular weight of about 150,000 using a gel filtration method. This protein was increased in 7 of 13 patients after SPG treatment.