KUNITZ TYPE MOLECULE-BASED VACCINE ELICITS ELEVATED SPECIFIC IGGS AND IGA ANTIBODIES AND TH1/TH17 RESPONSES AGAINST FASCIOLA HEPATICA

LEONARDO MICAEL SILVANE, DAIANA CELIAS, MALETTO BELKYS, FERNANDA SANCHEZ VALLECILLO, ANA CHIODETTI, ROMAGNOLI PABLO, CRISTINA MOTRAN, SANTIAGO PALMA, DANIEL ALLEMANDI, LAURA CERVI

Congreso; Reunión de Sociedad de Biociencias; 2017

Fasciola hepatica is a helminth parasite with a worldwide distribution, which can cause a chronic liver disease: fasciolosis, leading to economic losses in the livestock and public health in many countries. 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 with Kunitz type molecule (KTM), an inhibitor of serine proteases with a key role in the parasite survival, and CpG-ODN/Coa-ASC16, an adjuvant with capacity to induce Th1 and Th17 responses. Previous results showed the efficacy of the vaccination in mice which generates a reduction in the liver damage produced by the infection. The aim of this work was to investigate the immune response developed during KTM/CpG-ODN/COA-ASC16 immunization Animals were allocated in four groups of 4 each. BALB/c mice were subcutaneously inoculated with 10 μg of KTM in CpG-ODN/Coa-ASC16 on days 0-7-14. Control animals were inoculated the same days with CpG-ODN/Coa-ASC16 or PBS. On day 21, all animals were orally infected with 6 F. hepatica metacercariae. An additional group without treatment or infection was including as control. After 4 days of challenge the mice were euthanized. Mice vaccinated with KTM/CpG-ODN/Coa-ASC16 showed high levels of specific IgG1, IgG2a and IgA in plasma (Student test <0,05) compare with another groups. In addition, Increased IgA titers in intestinal lavage and feces (student test p<0,05) were observed. Igs detection were performed by ELISA Splenocytes from KTM/CpG-ODN/Coa-ASC16 immunized mice, KTM restimulated, secrete significant amounts of IL-17 and IFN-γ (Student test, p<0,05) by ELISA. These data suggest that the presence of elevated Th1-Th17 mixed responses and the high levels of IgGs and mucosal IgA antibodies, would be involved in the protection observed by KTM/CpG-ODN/Coa-ASC16 vaccination.