INVESTIGADORES
COCERES Veronica Mabel
artículos
Título:
Neospora caninum vaccine using recombinant proteins fails to prevent fetal infection in pregnant cattle after experimental challenge
Autor/es:
HECKER YP; VERÓNICA CÓCERES; WILKOWSKY SE ; JARAMILLO ORTIZ JM; MORRELL EL; VERNA AE; GANUZA A; CANO DB; LISCHINSKY L; ANGEL SO; ZAMORANO P; ODEON AC; LEUNDA MR; CAMPERO CM; MOREIN B ; PRANDO MOORE D
Revista:
VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 162 p. 142 - 153
ISSN:
0165-2427
Resumen:
The aim of the present study was to evaluate the immunogenicity andprotective efficacy of rNcSAG1, rNcHSP20, rNcGRA7 recombinant proteins
formulated with immune stimulating complexes (ISCOMs) in pregnant heifers
against vertical transmission of N. caninum. Twelve pregnant heifers were
divided into 3 groups of 4 heifers each, receiving different formulations before
mating. Immunogens were administered twice subcutaneously: group A animals
were inoculated with three recombinant proteins (rNcSAG1, rNcHSP20,
rNcGRA7) formulated with ISCOMs; group B animals received ISCOM-MATRIX
(without antigen) and group C received sterile phosphate-buffered saline (PBS)
only. The recombinant proteins were expressed in Escherichia coli and purified
in nickel resin. All groups were intravenously challenged with the NC-1 strain of
Neospora caninum at Day 70 of gestation and dams slaughtered at week 17 of
the experiment. Heifers from group A developed specific antibodies against
rNcSAG1, rNcHSP20 and rNcGRA7 prior to the challenge. Following
immunization, an statistically significant increase of antibodies against rNcSAG1
and rNcHSP20 in all animals of group A was detected compared to animals in
groups B and C at weeks 5, 13 and 16 (P <0.001). Levels of antibodies against
rNcGRA7 were statistical higher in group A animals when compared with
groups B and C at weeks 5 and 16 (P > 0.001). There were no differences in
IFN-ã production among the experimental groups at any time point (P > 0.05).
Transplacental transmission was determined in all fetuses of groups A, B and C
by Western Blot, Immunohistochemistry and nested PCR. This work showed
that rNcSAG1, rNcHSP20 and rNcGRA7 proteins while immunogenic in cattle
failed to prevent the fetal infection in pregnant cattle challenged 48 at Day 70 of
49 gestation.