Neutralization of IL-5 in Cd19CreRosaIL-2 mice prevented the eosinophilia (Figs. 8 L and S4 J), demonstrating that B cell–specific production of IL-2 initiated an unconventional cellular circuit expanding IL-5–expressing ILC2s and, downstream, eosinophils. Here, IL5 is linked to Increased total eosinophil count.