HSP20 PROTEIN FROM TOXOPLASMA GONDII GENERATES PROTECTION IN A MURINE MODEL OF CHRONIC TOXOPLASMOSIS

MARIANO SERGIO PICCHIO, NADIA ARCÓN, VANESA ROXANA SANCHEZ, IGNACIO MARTÍN FENOY, ARIADNA SOLEDAD SOTO, MARIA DE LOS ÁNGELES ALDIRICO, MATÍAS DAMIÁN PERRONE SIBILIA, ROSALÍA MORETTA, ALEJANDRA GOLDMAN, VALENTINA MARTIN

buenos aires

Simposio; Reunión Conjunta sociedades biociencias; 2017

Toxoplasma gondii is an intracellular protozoan with a worldwide prevalence inhuman and animal populations. No vaccine is currently available, so the design ofefficient vaccine strategies is still a topical question. The T. gondii surfacechaperone Hsp20 appears as a possible candidate to be included in thedevelopment of a preventive vaccine, since it is recognized by almost 80% of serafrom seropositive individuals and also, anti-Hsp20 antibodies are able to block invitro parasite motility and host cell invasion. In the present work, we studied theimmune response and protective effect of rHsp20 in C57BL/6 mice, a strain highlysusceptible to Toxoplasma infection. Mice were immunized 3 times with 15 day-intervals with rHsp20 alone (20μg/dose) by intranasal (rHsp20 IN) or intradermalroute (rHsp20 ID), or combined with Alum (rHsp20 ID+Alum) or complete Freund´sadjuvant (rHsp20 ID+ACF). Naive mice were used for the control group (Control).Two weeks after last immunization, mice were orally challenged with a non-lethaldose of tissue cysts of the ME49 strain. One month later, cysts were counted in thebrain of infected mice and a significant decrease in parasite load was observedonly in the group vaccinated with rHsp20+ACF (p