Many alternative treatment approaches, originating from Asia, are becoming increasingly popular in the Western hemisphere. Recently, an article published in a renowned journal reported that venom of apis mellifera (bee venom (BV)) and melittin mediate immune-modulating effects by blocking the activation of the transcription factor NF-kappaB. Such a modus operandi would corroborate the many claims of beneficial effects of BV treatment and give immediate credit to this form of therapy. Fibroblast-like synoviocytes from rheumatoid arthritis patients and dermal fibroblast cells and white blood cells from healthy volunteers were used to study the effects of BV and melittin on the activation of NF-kappaB and a series of genes that are markers of inflammation. EMSAs demonstrate that neither BV nor melittin blocked IL-1beta-induced NF-kappaB activation; neither did they affect phosphorylation or degradation of IkappaB. Contrary to published data, even high concentrations of BV and melittin were without any effect on NF-kappaB-p50-DNA interactions. More importantly, in fibroblast-like synoviocytes, but also in dermal fibroblasts as well as in mononuclear cells exposed to BV or melittin, mRNA levels of several proinflammatory genes are significantly increased, and Western blot data show elevated cyclooxygenase-2 protein levels. Furthermore, exposure to BV higher than 10 mug/ml resulted in disintegration of all cell types tested. In addition, large quantities of oxygen radicals are produced in a dose-dependent manner in leukocytes exposed to BV. Taken together, data presented in this work do not corroborate an earlier report regarding the effectiveness of BV as an inhibitor of the transcription factor NF-kappaB.