Login
MENU
Researchers from Texas Biomed and Scripps Research Institute have made significant strides in the development of a promising vaccine candidate against the Lassa virus, a pathogen responsible for causing Lassa fever, a disease that afflicts tens to hundreds of thousands of individuals across Western Africa annually. With no approved vaccine or cure currently available, Lassa fever represents a significant public health challenge, underscored by a mortality rate estimated between 15-20%.
The virus, transmitted from infected rodents to humans via contaminated food or surfaces, can lead to severe symptoms such as fever, bleeding, and organ failure, typically within two weeks of infection. Given its potential to ignite a public health emergency, the World Health Organization has prioritized Lassa fever for vaccine research and development.
Over the past decade, Professors Luis Martínez-Sobrido, PhD, and Juan Carlos de la Torre, PhD, have focused their efforts on producing a live-attenuated vaccine. Unlike other vaccines that target only a part of the virus, live-attenuated vaccines employ a weakened version of the entire virus, an approach that can potentially provide broader and more durable protection. This type of vaccine is already successfully used for several diseases, including measles, mumps, and yellow fever.
To achieve the desired attenuation in the Lassa virus, the research team ingeniously tweaked both sections of the virus's genome. Dr. Martínez-Sobrido's team employed codon deoptimization on the virus's small segment, reducing the production of a key protein necessary for the virus's ability to infect cells. Concurrently, Dr. de la Torre's team swapped part of the large segment RNA with that from the small segment, enhancing the attenuation process.
The dual-modification approach ensures a robust safety profile, reducing the virus's ability to replicate while preventing it from reverting to a virulent form. The combined changes make it improbable for the attenuated virus to regain disease-causing potential, even if it recombines with wild strains.
The results, achieved in collaboration with the NIAID's Integrated Research Facility at Fort Detrick, demonstrated striking efficacy in preliminary studies involving guinea pigs. In trials, 50 guinea pigs were divided between vaccinated and unvaccinated groups, subsequently exposed to a typically lethal dose of Lassa virus. Remarkably, the vaccinated group demonstrated complete protection without any adverse side effects.
"This vaccine provides 100% protection, which is exactly what you want," remarked Dr. Martínez-Sobrido on the promising outcome. The next phase of research will involve testing the vaccine in nonhuman primates, a critical step towards confirming its safety and efficacy before progressing to human clinical trials. This innovative vaccine candidate holds the potential to be a groundbreaking tool in the fight against Lassa fever, offering hope for controlling this serious disease in high-risk regions.
