Overview

• Researchers analyzed blood from 26 U.S. trial participants given two TAK‑003 doses 90 days apart and validated baseline differences in about 50 Singapore volunteers.
• Even before vaccination, dengue‑experienced individuals showed distinct gene‑expression patterns, indicating a long‑lasting reset in innate immune function.
• People with prior infection mounted stronger antibody responses after a single vaccine dose than dengue‑naïve individuals did after two doses.
• The persistent imprint was found in innate immune cells targeted by dengue, not in antibody‑producing memory cells, and included dampened immediate antiviral gene activity.
• Authors say the findings help explain better vaccine performance in seropositive people and could guide deployment of current shots and the design of next‑generation vaccines that safely mimic infection‑like training.