Evaluate Toxocara Canis Excretory-Secretory Antigens in Experimental Allergic Encephalomyelitis (EAE)

BACKGROUND: Toxocara canis is the most prevalent intestinal roundworm of canid species. OBJECTIVES: This study aims to evaluate the effects of Toxocara canis excretory- secretory antigens (TcES Ag) on modulating the immune system in Experimental Allergic Encephalomyelitis (EAE) model. METHODS: Adult worms of T.canis were collected from dogs to obtain excretory-secretory antigens. Female C57BL/6 mice were divided to four groups (5 mice in each) including: group 1 (MOG +TcES Ag), 2 (MOG), 3 (normal) and 4 (TcES Ag). EAE was induced in groups 1 and 2 using myelin oligodendrocyte glycoprotein peptide. Before EAE induction, TcES Ag was injected in group 1. Twenty-nine after EAE induction, mice spleens were removed. Mononuclear cells were cultured and used for RNA extraction.Real Time PCR was performed to evaluate RNA expression levels of T-bet (Th1 lineage-specific transcription factor), GATA-3 (Th2 transcription factor), and FOXP3 (Treg transcription factor). RESULTS: Our results indicated the clinical signs (disability score) of mice in group 1 were decreased significantly as compared to the control group. Gene expression of T-bet in the TcES Ag treatment group were noticeably diminished compared to MOG and normal group. The expression of GATA-3 gene in group 1 was lower than that in group 2. CONCLUSIONS: It seems that the TcES Ag may reduce disability score in multiple sclerosis EAE model, and other recombinant antigens should be examined.