IL-17 and IFN-γ in the establishment of the liver protection after vaccination with KTM during Fasciola hepatica infection

SILVANE LM, CELIAS DP, MALETTO BA, SÁNCHEZ VALLECILLO MF, CHIODETTI AL, MOTRAN C, PALMA SD, ALLEMANDI DA, Y CERVI LD

Mar del Plata

Congreso; LXIV reunión de la Sociedad Argentina de Inmunología; 2016

IL-17 and IFN-γ in the establishment of the liver protection after vaccination with KTM during Fasciola hepatica infectionSilvane LM1, Celias DP1, Maletto BA1, Sánchez Vallecillo MF1, Chiodetti AL1, Motran C1, Palma SD2, Allemandi DA2, y Cervi LD1lsilvane@fcq.unc.edu.ar1 Dpto. de Bioq. Clín. Fac. C. Qcas. Univ.Nac.Córdoba. CIBICI-CONICET. Córdoba, Argentina.2 Dpto de Farmacia, Fac. C. Qcas. Univ. Nac.Córdoba, UNITEFA (CONICET), Córdoba, ArgentinaKeywords : Fasciola hepatica, Vaccine, Kunitz type molecule, CpG-ODN/Coa-ASC16,IL-17,IFN-γThe liver fluke Fasciola hepatica infect livestock worldwide and threaten food security. Fascioliasis is also a food borne disease with up to 17 million humans infected. The prevailing control strategy based on anthelmintic drugs is unsustainable due to widespread resistance hence vaccination appears as an attractive option to pursue. In our laboratory we study a vaccine formulated by Kunitz type molecule (KTM), an inhibitor of serine proteases with a key role in survival of the parasite, and CpG-ODN/Coa-ASC16, an adjuvant with capacity for induce response Th1 and Th17.The first results showed that the formulation KTM/CpG-ODN/Coa-ASC16 reduce liver damage caused by the infection in mice. What remains now is to evaluate how this protection is developing.BALB/c mice were subcutaneously immunized with a solution of KTM/CpG-ODN/Coa-ASC16, CpG-ODN/Coa-ASC16 or saline buffer. Immunizations were performed at days 0, 7 and 14. Each mouse was immunized with an entire dose (250 µl) equally distributed at five sites: tail, back, the neck region and both hind limbs (50 µl/site). CpG-ODN was administered at 35 mg/mouse/dose. The KTM dose injected was 10 mg/mouse/dose. One week after the last vaccination, mice were challenged orally with 6 F.hepatica metacercariae and euthanized 25 days after challenge.Splenocytes from KTM/CpG-ODN/Coa-ASC16 group restimulated with KTM secrete significant amounts of IL-17 and IFN-γ (Student test, p<0,05).CD4 T cells were determined as responsible for release of IFN-γ. In the same way, peritoneal cells producting significant amounts of IFN-γ, TNF and IL-17 (Student test, p<0,05) in these vaccinated animals .Besides the peritoneal macrophages are increased in comparison with the other groups.This study suggests that KTM/CpG-ODN/Coa-ASC16 induce an immune response characterized by the secretion of IL-17 and IFN-γ, which, as noted in previous studies, it is responsible for the observed protection against F. hepatica.