Autolytic generation of dialysable components in extracts of VISCUM ALBUM exhibiting different mechanisms of enhancement of human NK-cytotoxicity against tumor cells

Journal/Book: Int-J-Immunopathol-Pharmacol 3 (2), 63-73. 1990;

Abstract: Fresh Viscum album extract and V. album extract Iscadorregistered trademark originally contained non-dialysable components which drasticallyincreased NK cytotoxicity when present during a 4h cytotoxicity assay incocultures of human peripheral blood mononuclear cells (PBMC) andK562-tumor cells. The mechanism of action is based on the bridging of NKcells and tumor cells by a V. album rhamnogalacturonan. Pre-treatment ofboth V. album extract samples at low temperatures led to degradation byendogenous plant hydrolases resulting in generation of two types ofdialysable components capable of enhancing human NK cytotoxicity bybasically different mechanisms. One of the active components stillexhibited the original type of NK cytotoxicity-enhancing activity,whereas the other type of active component originally not present,enhanced NK cytotoxicity in a lymphokine-like manner only during 72hpre-incubation of PBMC and had not to be present during the cytotoxicityassay. These dialysable components represent an antitumor potential ofhigh immunomodulatory value.

Keyword(s): Medical:natural-killer-cell

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