Assessment of vaccination with gamma radiation-attenuated infective Toxocara canis eggs on murine toxocariasis
- Author:
Hafez, E.N.
1
;
Awadallah, F.M.
2
;
Ibrahim, S.A.
2
;
Amin, M.M.
1
;
El-Nawasera, N.Z.
2
Author Information
- Publication Type:Journal Article
- From:Tropical Biomedicine 2020;37(No.1):89-102
- CountryMalaysia
- Language:English
- Abstract: Toxocara canis is a major parasite that infects many animals with high risk of human infections. This study aims at assessing the immunization with gamma radiationattenuated infective stage on rats challenged with non-irradiated dose. Level of vaccine protection was evaluated in liver and lung regarding parasitological, histopathological, biochemical and molecular parameters. Fifty rats were enrolled in three groups: group A (10 rats) as normal control; group B (20 rats) subdivided into subgroup B1 (infected control) and subgroup B2 infected then challenged after 14 days with the same dose of infection (challenged infected control); and group C (20 rats) subdivided into subgroup C1 vaccinated with a dose of 800 gray (Gy) gamma-radiated infective eggs (vaccine control) and subgroup C2 vaccinated then challenged on 14th day with same number of infective eggs (vaccinated-challenged). Tissues were stained with Haematoxylin and Eosin (H&E) for histopathological studies. Biochemical studies through detection of nitric oxide (NO) and Caspase-3 were conducted. Extent of DNA damage by Comet assay was assessed. Vaccinated-challenged subgroup revealed a marked reduction in larvae in tissues with mild associated histological changes. In addition there was accompanied reduction of NO, Casepase-3 level and DNA damage compared to the control infected group. It could be concluded that vaccination of rats with a dose of 800Gy gamma radiation-attenuated infective stage improves immune response to challenge infection and drastically reduces the morbidity currently seen.
- Full text:8.2020my1100.pdf
