Toxic Effects and Safety of Bee Venom Protein [Melittin] in Mice: Search for Natural Vaccine Adjuvants

Melittin protein is the main component of Bee venom (BV) that contains twenty-six amino acids. It constitutes 40% to 50% of dry bee venom by weight and is used in traditional medicine to inhibit infection and reduce inflammation. This study aimed to determine the toxic effects of melittin in CD-1 Swiss albino mice. The study also aimed to determine the lowest safe melittin dose to be used as a potential vaccine adjuvant. One hundred and sixty mice were injected intra-dermally with increasing doses of melittin [9000, 4500, 2250, 900, 450, 250, 100, 50 and 30 μg/dose]. The mice were followed for toxicity with respect to body temperature, body movement, weight, function/ anatomical structure of vital organs [brain, liver, bone marrow, kidneys]. Injected mice with high doses [9000, 4500, 2250 μg/dose] died with hypothermia, ataxia and loss of weight. Thirty μg /dose of melittin was found to be the lowest safe dose with minimum side effects and no abnormalities in histological sections of vital organs. Result concludes, melittin is safe with minimum sides in low doses. 30 μg/dose of melittin can be taken forward to determine its effects on the immune system as a potential vaccine adjuvant.