Strain differences in the cytotoxic activity and TNF production of murine macrophages stimulated by lentinan.

The effect of lentinan, a glucan type immunomodulatory polysaccharide was studied on the antitumor cytotoxicity and on the TNF secretion of peritoneal macrophages in inbred H-2 congeneic mouse strains under in vivo and in vitro conditions. The cytotoxic activity and TNF secretion of murine macrophages was found to be elevated by lentinan in vitro and in vivo conditions. The effectiveness of lentinan to induce cytotoxicity and TNF secretion was highly influenced by the genotype of the host. The increased cytotoxicity of macrophages was modified by the H-2 and the background genes. The black background and the H-2a and H-2d haplotypes were associated with high responsiveness, while the albino and agouti background and the H-2b and the H-2k haplotypes with low responsiveness to lentinan treatment. The degree of TNF secretion of macrophages stimulated by lentinan was influenced by the H-2 genes only. Similarly, to the macrophage cytotoxicity the TNF secretion in the H-2a and H-2d haplotypes were found to be high, on the other hand, in the H-2b and H-2k were low.