Beating Dengue Is In Your DNA (Vaccine)

A DNA-based vaccine against dengue, which would not require cold chain transport, has been shown to protect mice against two out of the four strains of dengue virus.

AsianScientist (July 12, 2017) – Researchers in China have developed an inexpensive, stable DNA vaccine that can protect against two of the four known serotypes of dengue virus. Their findings are published in Frontiers in Cellular and Infection Microbiology.

According to the World Health Organization, the dengue virus is one of the most rapidly spreading mosquito-borne pathogens worldwide. A tetravalent dengue vaccine that protects against all four serotypes of dengue virus (DV1-4) has been approved for use in some countries. However, in younger recipients, the tetravalent vaccine has been reported to increase the risk of severe dengue. Thus, it is still necessary to develop safer, more economical and more effective vaccines against dengue infection.

“Dengue is considered to be one of the fastest growing epidemics. Among the four distinct serotypes of dengue viruses, DV1 and DV2 are especially predominant serotypes,” explained Dr. An Jing of the Capital Medical University in China. “In 2014, the Guangdong province of China suffered from the most serious dengue outbreak in its history and co-circulation of DV1 and DV2 was identified. Dengue became endemic in China—its prevention is a long-term effort.”

DNA vaccination is a novel and rapidly developing approach for the prevention and therapy of disease. Modified circular DNA sequences (known as plasmids) that encode specific antigens are used to prime the body’s immune system against a particular infection. Unlike conventional vaccines, DNA vaccines are inexpensive, easy to produce and have greater vaccine stability. However, there is currently no licensed DNA vaccine available for humans.

“Our DNA vaccine candidate pVAX1-D1ME induced effective immune responses and protection in mice. Importantly, our bivalent vaccine generated a balanced immunity against DV1 and DV2 infection,” said An. “However, it was noted that the end-point titers of anti-DV1 and anti-DV2 in the bivalent vaccine-immunized mice were lower than those in the monovalent vaccine-immunized mice, indicating interference between the DV1 and DV2 vaccine candidates. This evidence should be considered in further research on dengue virus tetravalent vaccine.”

The research team hopes that their research will help advance the field of vaccine development against all four serotypes of dengue virus.

“We are developing a dengue tetravalent DNA vaccine and evaluating the immunogenicity in animal models,” said An. “Our final goal is to translate the DNA vaccine candidates and optimize them for clinical application. Our preliminary research data are open, and we would like the results to be used not only by universities and researchers, but also by companies for further cooperation.”



The article can be found at: Zheng et al. (2017) Effective Protection Induced by a Monovalent DNA Vaccine Against Dengue Virus (DV) Serotype 1 and a Bivalent DNA Vaccine Against DV1 and DV2 in Mice.

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Source: Frontiers; Photo: Shutterstock.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

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