Polysaccharide Lentinan-Treatment Combined with Inflammatory Agent Augments Antitumor Activity of LAK Cells

Abstract

Lentinan(LNT) isolated from Lentinus edodes is a neutral ß(1–3) glucan type polysaccharide and possess no mitogenicity and toxicity for both normal and tumor cells. A number of previous studies undertaken mainly by Dr. Chihara’s group(Hamuro and Chihara 1985) has demonstrated that LNT possess in general two kinds of characteristics; one is immunological nature and the other is biological nature. Main immunological natures reside in the stimulation or potentiation of the T cell — macrophages — NK cell synergism in vivo, by which exert nonspecific immunoprophylaxis. Other noteworthy nature is the vascular dilatation and hemorrhage activity, indicating that LNT can exert direct or indirect action on the vascular system(Maeda et al. 1984). The present study aimed to define immunopotentiating action of LNT, focussing in particular on the synergistic action of LNT and lymphokine activated killer(LAK) cells on the suppression of autologous tumor-growth, in the context of LAK cell-extravasation into tumor tissues.