Characterization of leptospiral proteins that afford partial protection in hamsters against lethal challenge with Leptospira interrogans.
Leptospirosis is a worldwide zoonosis caused by pathogenic Leptospira. The whole-genome sequence of Leptospira interrogans serovar Copenhageni together with bioinformatic tools allow us to search for novel antigen candidates suitable for improved vaccines against leptospirosis. This study focused on three genes encoding conserved hypothetical proteins predicted to be exported to the outer membrane. The genes were amplified by PCR from six predominant pathogenic serovars in Brazil. The genes were cloned and expressed in Escherichia coli strain BL21-SI using the expression vector pDEST17. The recombinant proteins tagged with N-terminal 6xHis were purified by metal-charged chromatography. The proteins were recognized by antibodies present in sera from hamsters that were experimentally infected. Immunization of hamsters followed by challenge with a lethal dose of a virulent strain of Leptospira showed that the recombinant protein rLIC12730 afforded statistically significant protection to animals (44 %), followed by rLIC10494 (40 %) and rLIC12922 (30 %). Immunization with these proteins produced an increase in antibody titres during subsequent boosters, suggesting the involvement of a T-helper 2 response. Although more studies are needed, these data suggest that rLIC12730 and rLIC10494 are promising candidates for a multivalent vaccine for the prevention of leptospirosis.
Atzingen
Marina V
MV
Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
Gonçales
Amane P
AP
Laboratório de Zoonoses Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, USP, Avenida Prof. Dr Orlando Marques de Paiva 87, 05508-270 São Paulo, SP, Brazil.
de Morais
Zenaide M
ZM
Laboratório de Zoonoses Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, USP, Avenida Prof. Dr Orlando Marques de Paiva 87, 05508-270 São Paulo, SP, Brazil.
Araújo
Eduardo R
ER
Instituto de Medicina Tropical, Departamento de Patologia, Faculdade de Medicina, USP, Avenida Dr Enéas Carvalho de Aguiar 470, 05403-000 São Paulo, SP, Brazil.
De Brito
Thales
T
Instituto de Medicina Tropical, Departamento de Patologia, Faculdade de Medicina, USP, Avenida Dr Enéas Carvalho de Aguiar 470, 05403-000 São Paulo, SP, Brazil.
Vasconcellos
Silvio A
SA
Laboratório de Zoonoses Bacterianas do VPS, Faculdade de Medicina Veterinária e Zootecnia, USP, Avenida Prof. Dr Orlando Marques de Paiva 87, 05508-270 São Paulo, SP, Brazil.
Nascimento
Ana L T O
ALTO
Interunidades em Biotecnologia, Instituto de Ciências Biomédicas, USP, Avenida Prof. Lineu Prestes 1730, 05508-900 São Paulo, SP, Brazil.|Centro de Biotecnologia, Instituto Butantan, Avenida Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology; D003001:Cloning, Molecular; D006224:Cricetinae; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D007921:Leptospira interrogans / Q000276:immunology* / Q000378:metabolism*; D007922:Leptospirosis / Q000276:immunology / Q000517:prevention & control*; D008297:Male; D008647:Mesocricetus; D008969:Molecular Sequence Data; D013997:Time Factors
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D001428:Bacterial Vaccines