Dengue Vaccine

Researchers from Vanderbilt University and National University of Singapore have determined the structure of human monoclonal antibody that can neutralise the deadly dengue virus. In lab tests conducted on a mouse model the antibody prevented dengue virus from fusing with its target cell thus preventing infection.

The development could lead to an effective vaccine against dengue virus that infects around 390 million people annually and is a major reason for high deaths in the tropics. For the study, scientists used cryo-electron microscopy to freeze samples at very low temperatures so they could visualise antibody-antigen binding to the atomic level. By doing so, they were able to identify human monoclonal antibody against dengue virus type 2 (DENV2) that locked across an array of envelope proteins.

Dengue is a complex of four distinct but related mosquito-borne viruses. These four distinct viruses are classified as serotypes which contain different antigens, or proteins on the viral envelope that elicit immune responses. A major challenge in treating dengue is that vaccines target only one serotype at a time which gives a leeway to other three serotypes to enhance infection. The study was published in the journal Science.