INVESTIGADORES
MARTIN Valentina
congresos y reuniones científicas
Título:
Vertical Toxoplasmosis in a Murine Model. Protection after Immunization with the serine protease inhibitor-1 of Toxoplasma gondii
Autor/es:
PICCHIO, MARIANO; SÁNCHEZ, VANESA; FENOY, IGNACIO; ARCÓN, NADIA; SOTO, ARIADNA; URRUTIA, MARIELA; GOLDMAN, ALEJANDRA; MARTIN, VALENTINA
Reunión:
Congreso; X Congreso de la Sociedad Argentina de Protozoología; 2014
Resumen:
Primary Toxoplasma gondii infection during
pregnancy can cause severe damage to the fetus as a result of congenital
transmission in humans and abortion and loss of offspring in farm animals. The
fact that infection before pregnancy normally results in
immunity able to protect the fetus, suggests the possibility of blocking parasite
vertical transmission by an appropriate vaccine. We
have previously shown that the T. gondii serine
protease inhibitor-1 (TgPI-1) induced a protective immune response against parasite infection in both C3H/HeN
and C57BL/6 mice. In the present work, we evaluated its protective capacity to
prevent parasite vertical transmission in BALB/c mice. Female mice were
immunized with rTgPI-1 (2 doses + alum id plus 2 doses +CpG-ODN in) or left
untreated (control group), and then mated with males. Pregnant dams were infected orally on day 12 of gestation, with tissue
cysts of T. gondii Me49 strain. Naturally delivered pups from rTgPI-1
vaccinated mice showed a significant increase in the neonatal survival rate on
day 30 after birth compared to the control group (71% vs 40%). On the other
hand, both groups presented similar rate of dead pups at birth (30% TgPI-1 vs
44% control). In order to evaluate whether TgPI-1 immunization could prevent Toxoplasma-induced fetal resorption, in
another experiment the uteri of pregnant mice were removed on day 19/20 of
gestation for the documentation of the implantation sites. A similar number of
dams experienced abortions in both control and vaccinated groups (57% 50%), but
the abortion rate in the control group was significantly higher compared to the
vaccinated group (100% vs 17%, p<0.05). In fetus with visible normality, a similar rate of
congenital infection was found as analyzed by Nested-PCR (41% vs 38%,
vaccinated vs control). These results let us hypothesize that vaccination with
rTgPI-1 could decrease the abortion rates and also increase the survival of
pups born to dams infected during pregnancy.