Typing of immunomodulators in terms of their effects on the electrophoretic pattern of serum proteins and antitumor combination therapy based on this typing.

Changes of serum proteins have recently received much attention in studies of immunomodulators. In this work, changes of serum proteins, especially LB, were studied by gel electrophoresis of sera after administration of 23 immunomodulators or antitumor agents. Fourteen of the 23 compounds increased the concentration of LB in the serum of normal ddY mice when injected once ip. Six compounds caused a very rapid (day 1) increase of LB, and 8 agents caused a slow increase (day 4 approximately day 10). On the basis of the results, these compounds were classified into type I (causing a rapid increase in LB; i.e., lipopolysaccharide, dextran sulfate and poly (I)-poly(C), type II (causing a slow increase in LB; i.g., lentinan, TAK and PS-K), and type O (causing no increase in LB; e.g., levamisole and bestatin). The antitumor activities of these three types of compounds in combination with lipopolysaccharide (type I) or lentinan (type II) were studied in an Ehrlich carcinoma-ddY mouse system. The results suggested that different types of compounds frequently showed synergistic antitumor activities. Typing of immuno-modulators and the antitumor activities of combinations of these compounds are discussed.