Effect of Egyptian Propolis Extract as an Adjuvant with Irradiated Cancer Vaccine against Ehrlich Ascites Carcinoma in Mice

Document Type : Original Article

Abstract

 PROPOLIS is a non-toxic natural substance with multiple pharmacological properties including anti-cancer and antioxidant. The objective of this study was to investigate the effect of Egyptian propolis extract (Prop) as an adjuvant co-injected with irradiated tumour cell lysate vaccine (Irr-V) against Ehrlich ascites carcinoma (EAC) in mice. Animals were divided into five equal groups (n=10). Control group. EAC group; injected with viable EAC (2x105/mouse) in the right thigh. EAC-Prop group; injected subcutaneously (Sc) with Prop (0.4mg/ mouse) weekly for three times, then after 2 weeks mice were received EAC viable cells (the day of challenge). Irr-V group; vaccinated with irradiated EAC cell lysate weekly for three times at a dose of 0.2μl in the right thigh. Prop-Irr-V group; vaccinated as Irr-V group, and treated with Prop as EAC-Prop group. Two weeks post the last treatment; animals of groups 4 and 5 were challenged with normal viable EAC (2x105/mouse) in the opposite thigh. Results: The results revealed a decrease in red blood cells (RBC) count, haematocrite value (Hct) and haemoglobin content (Hb) and an increase in total leucocytes, absolute lymphocyte and neutrophil counts in EAC-bearing mice. Furthermore, oxidative stress identified by a decrease in glutathione (GSH) content and superoxide dismutase (SOD) activity associated with an increase in the content of advanced oxidation protein products (AOPP) and malondialdehyde (MDA) were recorded in the liver and blood tissues of EAC-bearing mice. Propolis, Irr-V as well as Irr-V-Prop treatment improved haematological toxicities and oxidative stress in EAC-bearing mice. However, improvement was more pronounced in Irr-V-Prop group and the cell viability assay, the tetrazolium dye;3-(4,5-dimethylthiazol-2-yl)-2,5-iphenyltetrazolium (MTT) showed a significant decrease in viable cells compared to each treatment alone. It could be concluded that Prop extract might be used as an adjuvant for irradiated cancer vaccines in cancer therapy.

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