Vaccination with gamma radiation-attenuated Toxoplasma gondii protects against ovarian infiltration in mice-bearing Ehrlich ascites carcinoma

Abstract

Purpose: Cancer is one of the most common causes of mortality and morbidity worldwide. Vaccines have been emerged as an attractive approach for their capacity of eliciting long-term immune response targeting cancer cells. Attenuated avirulent Toxoplasma gondii stimulate immunity and activate antitumor cells thereby eliciting rejection of some established cancer. The purpose of this study was to evaluate the antitumor-protective capacity of vaccination with gamma radiation-attenuated T. gondii against ovarian penetration in Ehrlich ascites carcinoma (EAC)-bearing mice.

Materials and methods: Forty-five mice were randomly divided into three groups as follows: nontumor-bearing (normal control); EAC-bearing group (EAC); and mice vaccinated orally with gamma radiation-attenuated T. gondii then inoculated 2 weeks later with EAC (TG + EAC). Survival rate, serum interleukin-12 (IL-12), and levels of IFN-γ mRNA, CD4, and CD8 in ovarian tissues homogenate were assessed. Also, ovarian histopathology and immunohistochemical expressions of metalloproteinase-2, CD34, and vimentin were determined.

Results: The group vaccinated with attenuated T. gondii showed significantly increased survival rates, serum IL-12, and levels of IFN-γ, CD4, and CD8 in ovarian tissue homogenates as well as an enhancement of histopathological and immunohistochemical changes compared to EAC-bearing group.

Conclusion: Vaccination with gamma radiation-attenuated T. gondii has the capacity to supply immunoprotective impact against ovarian invasion in EAC-bearing mice.

Keywords:

• Toxoplasma gondii
• gamma radiation
• Ehrlich ascites carcinoma
• ovary
• immunohistochemistry

Acknowledgements

The authors acknowledge the assistance given by the National Center of Radiation Research and Technology, which provided all facilities for this study.

Disclosure statement

The authors declare that they have no competing interest.

Additional information

Notes on contributors

Eman N. Hafez

Eman N. Hafez, MD, is an Associate Professor of Parasitology in Health Radiation Research Department in National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Hanan M. G. Youssef

Hanan M. G. Youssef, PhD, is an Assistant Professor of Gynecology in Health Radiation Research Department in National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.

Hanan A. El-Kabany

Hanan A. El-Kabany, is a Professor of Biochemistry in Health Radiation Research Department in National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt.