La Jolla Institute researchers find dengue immunity can protect against Zika virus

Researchers at the La Jolla Institute for Allergy and Immunology recently found that immunity to dengue can defend against the Zika virus and identified cytotoxic T-cells that can protect against both infections.

“In some parts of the world Zika is almost like a secondary infection,” Sujan Shresta, an associate professor in LJI’s Center for Infectious Disease, said. “It has spread into Brazil/Latin America and is moving into places in Asia where people previously had dengue. Our new work suggests that vaccines targeting either virus could be engineered to induce both T cell and antibody responses effective to protect people in these areas.”

Shresta’s team infected mice with dengue virus and, once they recovered, inoculated those mice with ZIKV. Overall, the mice did not show reduced burden of ZIKV in blood and tissues.

In a separate experiment, the scientists isolated cytotoxic T cells from the blood of dengue-immune mice and injected them into normal mice. When exposed to ZIKV, the mice with the injected T-cells showed resistance to Zika.

“Approved vaccines for many diseases work by inducing antibody responses,” Shresta said. “But now we are dealing with problematic diseases, like dengue and Zika for which we cannot rely solely on raising antibodies. Certain pathogens are likely to also require a T-cell response.”