Melittin, an active ingredient of honeybee venom (apis mellifera)‎, as a potent inhibitor of tumor growth in mice through stimulation of the immune response

الملخص EN

Recent interest in the action of melittin, as an immunostimulator, should result in research of its intimate relationship with a wide range of incurable degenerative and malignant diseases.

The objective of the present study was to investigate the immunostimulatory effect of melittin pre-treatment against Ehrlich tumor growth in mice both in vivo and in vitro and the possible mechanism(s) of antitumor activity.

Subcutaneous injection of melittin with doses (0.5, 5 and 50 ?g/100 g b.wt, every other day for consecutive 4 weeks) before inoculation of Ehrlich ascite tumor (EAT, 1x106 cells) to mice elicited a significant increase in the cellularity of both thymus and bone marrow lymphocytes as well as peritoneal macrophages.

Melittin pre-treatment activated the phagocytic function of macrophages, as well as T- and B-cell functions, and recovered both liver and kidney functions.

Melittin pre-treatment also decreased the proliferation of tumor cells incubated in the peritoneal cavity of mice, and decreased their viability percentage in vitro.

When measured morphometrically and examined histologically, the solid Ehrlich tumor was significantly reduced in size.

The present study proposed that melittin has indirect mechanism of tumor growth inhibition that is based on activation of both cell-mediated and humoral immune responses.