Other positive correlates with IgE included the costimulatory receptor ICOS, the gut-homing integrin ITGA4, and PLA2G16 and GK, two transcripts implicated in the production of prostaglandin-D2 by peTh2 cells in eosinophilic esophagitis (42), whereas transcripts negatively correlated with IgE production included TGFB1, which is associated with class-switching to IgA (43, 44), and TNFSF10, which has been demonstrated to dampen Th2 responses in allergic asthma (ref. 45 and Supplemental Figure 11). This evidence concerns the gene ICOS and allergic asthma.