TPH2 and allergic asthma: As expected, the frequency of CD27+CD38+ plasmablasts, CD24hiCD38hi transitional B cells, CXCR5− Tph, CXCR5−ICOS+PD-1+ Tph, Tph2 subtypes and Tfh2 subtypes were weak positively correlated with serum total IgE level in children with allergic asthma (Fig. 3A-F).