Fig. 2.

Phenotypical and functional differences of Tfh cells in patients with varying severity of acute dengue. The frequency of PD-1 + ICOS+ co-expressing Tfh cells (a), the frequency of Tfh cells expressing PD-1+ alone (b), ICOS alone (c), and those which produce IL-21 (d) were measured in patients with acute DENV2 infection (n = 40), in healthy individuals (n = 12), in patients with DF (n = 18) and DHF (n = 22). The frequency of the total Tfh cells (e) and IL-21 producing cells (f) were compared in a subset of these patients (n = 14) during the acute and the convalescent phase of illness. The lines display the median and the IQR. *P < 0.05, **P < 0.01, ***p < 0.001, ****p < 0.0001