Identification of the Hemolysis-Associated Protein 1 as a Cross-Protective Immunogen ofLeptospira interrogansby Adenovirus-Mediated Vaccination

Abstract

New vaccine strategies are needed for the prevention of leptospirosis, a widespread human and animal disease caused by pathogenic leptospires. Our previous work determined that a protein leptospiral extract conferred cross-protection in a gerbil model of leptospirosis. The 31-to 34-kDa protein fraction of Leptospira interrogans serovar autumnalis was shown sufficient for this purpose. In the present study, N-terminal sequencing of a 32-kDa fraction and Southern blotting of genomic DNA with corresponding degenerated oligonucleotide probes identified two of its constituents: hemolysis-associated protein 1 (Hap1) and the outer membrane Leptospira protein 1 (OmpL1). Adenovirus-mediated Hap1 vaccination induces significant protection against a virulent heterologous Leptospira challenge in gerbils, whereas a similar OmpL1 construct failed to protect the animals. These data indicate that Hap1 could be a good candidate for developing a new generation of vaccines able to induce broad protection against leptospirosis disease.

Protection of Guinea Pigs against Leptospira interrogans Serovar Lai by LipL21 DNA Vaccine

“…Moreover, when used with adenovirus or DNA vaccine vectors, LipL32 provided significant protection in gerbils. However, it failed to provide sufficient protection when used as a recombinant protein vaccine (22,23). This may be due to the fact that recombinant protein can induce humoral immune response only, whereas delivery with adenovirus or DNA vaccine vector can stimulate both humoral and cell-mediated immunity.…”

Identification of a novel antigen of pathogenic Leptospira spp. that reacted with convalescent mice sera

“…OmpL1 and LipL41 have been shown to induce synergistic immunoprotection in hamsters (Haake et al, 1999). Adenovirus-mediated vaccination of Hap1 (also known as LipL32) induced protection in gerbils (Branger et al, 2001). The LAg42 protein may be one of the candidates for such new vaccines; however, further studies are required to evaluate its relevance.…”

“…This result indicates that leptospiral proteins are potential candidates for a new vaccine that generates broad cross-protection beyond serovars. Identification of immunogenic proteins of leptospires has thus been attempted and some leptospiral proteins, such as LipL41, OmpL1 and Hap1 (also known as LipL32), are found to be protective immunogens that are conserved among pathogenic leptospires (Branger et al, 2001;Haake et al, 1999).…”

Eficacia y seguridad de una vacuna contra la leptospirosis humana en Cuba

“…Estas células se inoculaban en medios de cultivo que contenían suero de origen animal, componente que solía causar reacciones adversas importantes (19,20). La inmunización con vacunas polivalentes contra la leptospirosis se ha aplicado en países como China y Japón, donde la incidencia de esta enfermedad es alta entre las personas que se dedican al cultivo del arroz (21).…”