Evidence of cross-protection within Leptospira interrogans in an experimental model

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

“…The current available vaccines based on inactivated whole bacteria or membrane preparations from pathogenic leptospires have shown some drawbacks. These include very low efficacy, an unacceptable side-effect profile, the requirement for annual booster immunizations, and failure to confer cross-protective immunity against different serovars (2,5,17). Generally, however, these vaccines do provide protection against the lethal onset of the disease, although they do not prevent persistent shedding from infected humans and animals (18).…”

“…In addition, it cannot provide cross-protection against the large number of pathogenic leptospires serogroups (5). Thus, new vaccine strategies are needed for the prevention of leptospirosis.…”

“…Additionally, these immunogens can be administered repeatedly without inducing anti-vector immunity (6). 5 These authors contributed equally to this work; LipL21 is the second major outer membrane protein in Leptospira interrogans serovar Lai, which has exhibited potent immunity capabilities (7), indicating that the lipL21 gene is a potent candidate gene for the prevention of the disease. Therefore, we initially constructed eukaryotic expression vector pcDNA3.1(+)-lipL21 and subsequently tested the effect of recombinant vector's immunization.…”

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

“…Leptospiral LPS is a protective immunogen that is generally specific for each serovar (serogroup) (Faine et al, 1999). In contrast to LPS, however, protein extracts prepared from a pathogenic Leptospira isolate can induce protective immunity against challenge with a heterologous serovar in an experimental animal model (Sonrier et al, 2000). This result indicates that leptospiral proteins are potential candidates for a new vaccine that generates broad cross-protection beyond serovars.…”

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

“…En un estudio realizado en Israel en 1973 con una vacuna autóctona sin proteínas séricas aplicada a personas en riesgo se alcanzó un nivel de seroconversión de 57% (22). Para que una vacuna sea eficaz no solo tiene que cumplir con los requisitos tecnológi-cos, sino que también se debe preparar a partir de cepas que respondan a los serotipos de mayor circulación en el área (25). La eficacia específica alcanzada por la vacuna aquí estudiada fue de 78,1%, comparable con la notificada para vacunas de características similares en ensayos de eficacia realizados en China y Rusia (21,23,26).…”