Evaluation of immunostimulatory effect of lacvobacillusspp. expressing ctxB ltb, in poultry challenged with Salmonella enteritidis

• Grant number: 09/53570-3
• Support type: Regular Research Grants
• Duration: September 01, 2010 - February 28, 2013
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal researcher: Raphael Lucio Andreatti Filho
• Grantee: Raphael Lucio Andreatti Filho
• Home Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The genus Lactobacillus is one of the main colonizers of avian gastrointestinal tract and has relevant immunological functions, such as stimulate the secretion of intestinal immunoglobin from class A (IgA). Recently, its application as a vehicle of oral vaccine has been intensified, in function of its characteristics of survival to gastric enzymes, colonization and adherence to the avian intestinal epithelium and imunoestimulation. There is information in literature that certain genes, such as ctxB and ltb subunit B from cholera toxin and enterotoxin thermolabile of Escherichia coli, respectively, act as a mucosa imunoestimulant. For these reasons, the objectives of the present study are to clone and express the genes ctxB and ltb in samples of Lactobacillus spp., in order to verify the occurrence of an increase in imunoestimulatory capacity of recombinant samples. For this purpose, bacterial samples of Lactobacillus spp. genus will be identified through polymerase chain reaction (PCR) and sequencing. Next, they will be tested for adhesion capacity on avian enteric tract The samples that present the best results for adhesion will be selected and transformed with the recombinant plasmids, containing the genes ctxB and lib cloned in the vectors pIA51acGFP and pIA51acll33PVA. After the confirmation of transformation and expression, the recombinant samples of Lactobacillus will be evaluated in vivo tests with IgA and IgG quantification by ELISA tests. And finally, the groups treated with recombinant Lactobacillus will be challenged with Salmonella Enteritidis. At the end of (his investigation it is expected to clone and express the genes ctxB and ltb in Lactobacillus spp., obtain solid information on imunoestimulatory capacity of these recombinant samples, as well as the secretory function of IgA on control of Salmonella Enteritidis infection. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BAPTISTA, A. A. S.; DONATO, T. C.; GARCIA, K. C. O. D.; GONCALVES, G. A. M.; COPPOLA, M. P.; OKAMOTO, A. S.; SEQUEIRA, J. L.; ANDREATTI FILHO, R. L.. Immune response of broiler chickens immunized orally with the recombinant proteins flagellin and the subunit B of cholera toxin associated with Lactobacillus spp.. POULTRY SCIENCE, v. 93, n. 1, p. 39-45, JAN 2014. (09/53570-3)