Polyclonal B cell activation after dengue infection.

<p>Fresh blood samples of dengue and control fever patients were analyzed by flow cytometry at 1–3, 4–7 and 15–25 days after onset of fever. A) CD19⁺CD20⁻CD27⁺CD138⁻ plasmablasts and CD27⁺CD138⁺ plasma cells (B) as % of lymphocytes. squares: other febrile illness (OFI), triangles: primary or secondary dengue infection. Each symbol represents one patient, lines indicate the mean. A Mann-Whitney test was used for statistical analysis. C) Gating strategy for plasmacells and plasmablasts. One secondary dengue patient with high plasma blast formation is shown. Blood was taken 3, 4 and 20 days after onset of fever.