Abstract: A process is provided for the purification of a proteinaceous physiologically active substance having antitumor activity, which is induced by administering to a rabbit at least one substance having a capacity for stimulating reticuloendothelial system and then injecting endotroxin from a Gram-negative bacterium into the rabbit. The process comprises contacting a crude solution of said proteinaceous physiologically active substance with a basic anion exchanger to have said physiologically active substance adsorbed on the anion exchanger, eluting the adsorbed physiologically active substance, and subjecting the eluate containing said physiologically active substance to gel filtration with a gel suitable for separation of a substance with a molecular weight in the range of 30,000 to 70,000. The purified preparation of said physiologically active substance thus obtained may be used as an antitumore agent for the treatment of malignant tumors.

Abstract: Human TNF(LuKII) having a specific activity of at least 1.5.times.10.sup.5 units per milligram of total protein is produced by contacting a TNF-containing protein composition, which has been harvested from human cell lines of hematopoietic origin or recombinant origin, in separate adsorption stages with glass beads, lentil lectin bound to Sepharose, and procion red agarose, thereby selectively to adsorb TNF in each stage, while leaving some impurities unadsorbed, each contact stage being followed by contact of the adsorbent with an eluant thereby to obtain a solution of more highly purified TNF after each stage. The purified human TNF(LuKII) is used to produce monoclonal antibodies against TNF(LuKII) and such antibodies can be used to assay samples for the presence of TNF(LuKII).

Abstract: A process for predicting the sensitivity of cells, e.g., tumor cells, to the effects of tumor necrosis factor or lymphotoxin involving ascertaining the binding of the tumor necrosis factor or lymphotoxin to the cells, i.e., measuring the number of receptors on the cells.