Kunitz type molecule in a liquid cristal nanostructure as vaccine platform against Fasciola hepatica infection in sheep

MARÍA DEL ROSARIO AHUMADA; CONSTANZA MARIN², CRISTIAN MENA², LORENA GUASCONI2, LAURA CHIAPELLO², BELKYS ANGÉLICA MALETTO, LEONARDO SILVANE; PALMA SD; BETTOLLI F; RODRIGO SANABRIA, CÉSAR PRUZZO ; DANIEL ALBERTO ALLEMANDI⁶; LEONARDO SILVANE2; . CERVI L.

Congreso; . LXIX Reunión Annual de la Sociedad Argentina de Inmunología (SAI); 2021

Fasciolosis is a parasitic disease that affects livestock causing hugeeconomic losses. It is also considered by the WHO as an emergingdisease. Triclabendazole is the antiparasitic of choice, howeverthe resistance to this drug has been reported. The development ofvaccines against F. hepatica is an alternative of choice for the controlof this disease. In this context, our laboratory has developed avaccine based on F. hepatica Kunitz-type molecule (FhKTM) as anantigen formulated with a nanostructure formed by self-assemblyof 6-O-ascorbyl palmitate ester (Coa-ASC16) and oligodeoxynucleotidecontaining unmethylated cytosine-guanine motifs (CpG-ODN)which induces protection against F. hepatica challenge in mice.Based on these results we immunized lambs, one of the natural hostof this disease, and test the ability of the vaccine to induce protectionand humoral response.Two immunizations were performed with an interval of 21 days withFhKTM/CpG-ODN/ Coa-ASC16 in six month old Creole biotypelambs. A control group was immunized with CpG-ODN/Coa-ASC16.Thirty days later, the experimental infection was performed with 100metacercariae per animal in all groups (vaccinated, infected andcontrol). After eight weeks egg count, number of adults in the liver,total eggs/ adult and IgG antibody titers were evaluated. The datawere statistically analyzed using the T test for difference of meansand ANOVA for evaluation of variances. The results show statisticallysignificant differences (p