Potential vaccine of Kunitz type protein formulated with a nano liquid crystal structure against Fasciola hepatica

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

Buenos Aires

Congreso; Latin American Society for Immunodeficiencies (LASID), Sociedad Argentina de Inmunologia (SAI), French Society for Immunology (SFI); 2015

Sociedad Argentina de Inmunologia

Fasciola hepatica is a worldwide distributed helminth parasite that causes great economic losses in sheep and cattle. Triclabendazol has been the drug of choice against fascioliasis. However, the continuing efficacy of this drug is at risk as resistance is emerging. Our research is focusing on developing new approaches, such as effective vaccine therapy, to control this disease.Kunitz type molecule (KTM) is a serine protease expressed in both juvenile and adult stage of the life cycle and is important for parasite feeding.We use a recombinant of KTM formulated with CpG-ODN with coagel formed by self-assembly of 6-O-ascorbyl palmitate (CpG-ODN/Coa-ASC16), a promising adjuvant with capacity for induce response Th1 and Th17.BALB/c mice were subcutaneously immunized with a solution of KTM/CpG-ODN/Coa-ASC16 or CpG-ODN/Coa-ASC16 or saline buffer. Immunizations were performed at day 0, 7 and 14. CpG-ODN was administered at 75 µg/mouse/dose, KTM at 20 µg/mouse/dose. One week after the last vaccination, mice were challenged orally with 6 F.hepatica metacercariae and euthanized 25 days after challenge.The pathological lesions of liver as well as alanine transaminasa (ALT) levels in vaccinated with KTM/CpG-ODN/Coa-ASC16 were significantly lower when compared with control groups (only infected mice) (p >0.05 Student T Test) indicating that vaccinated mice had reduced liver parenchyma damage. The levels of KTM specific IgG1 detected by ELISA, was significantly increased in KTM/CpG-ODN/Coa-ASC16 immunized mice compared with control infected group.This study suggests that KTM/CpG-ODN/Coa-ASC16 has a potential as a vaccine candidate against F. hepatica in mice, and this possibility could be tested in ruminants.