ASSESSING THE IMMUNOPROPHYLACTIC PROPERTIES OF A NOVEL CHIMERIC ANTIGEN CANDIDATE TO CONTROL TRYPANOSOMA CRUZI INFECTION

MARÍA ELISA VÁZQUEZ; BRENDA ZABALA; ANDREA C. MESÍAS; CECILIA PARODI; CORBALÁN ,NATALIA S.; BLADIMIRO LENIS; LUCÍA BISCARI; ANDRÉS ALLOATTI; PÉREZ BRANDÁN, CECILIA; ACUÑA L

Mar del Plata

Congreso; REUNIÓN CONJUNTA SAIC SAI&FAIC SAFIS 2022; 2022

SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA (SAIC);SOCIEDAD ARGENTINA DE INMUNOLOGÍA (SAI) & SOCIEDAD ARGENTINA DE FISIOLOGÍA (SAFIS)

Chagas disease (CD) is a neglected tropical disease, affecting morethan 8 million people worldwide. Patients with CD develop myocarditis and/or digestive clinical manifestations. The agent responsiblefor this disease is Trypanosoma cruzi, a parasite that can persistin its mammalian host because it has evolved multiple strategiesto evade the immune response. This persistence is considered themain factor contributing to the late symptoms of CD. The aim ofthe present work is to depict the immunological outcome of a newantigen candidate in a prime/boost/challenge mouse model of infection. For this, animals were given three doses, in conjunction with asaponin type adjuvant, of a chimeric antigen composed of fragmentsof two immunogenic defined proteins of the parasites. Around day20 post boost serum samples were taken to measure specific antibodies response and half of them were later sacrificed for spleenremoval. Cytokines production after in vitro splenocytes re-stimulation and memory T cells subsets were analyzed. The other halfof animals were challenged with virulent T. cruzi parasites. Duringinfection period parasite load in blood was recorded twice a week totest vaccine efficiency. After that animals were sacrificed and heart,colon and skeletal muscle were taken to analyze parasite burdenand histological damage. Briefly, mice vaccinated with the chimera were capable to produce specific antibodies. Regarding memoryT-cells, no significative differences were found among experimentalgroups; however, IL-10 levels were lower in vaccinated animals thanin control groups. Interestingly, mice inoculated with our chimerawere able to control parasite load in blood during the first days ofinfection and dimmish parasite burden in targeted tissues exhibitingminor inflammation and preventing parasite nesting. This study reveals the immunological potential of this chimeric protein as new immunogen to use in vaccine formulations to defeat T. cruzi infection.