What are TH2 cells? And what cytokines they produce?

Th2 and Tfh stimulate production of IgE by B cells. IgE coat helminths, then eosinophils bind via Fc receptors and release toxic granule content. Similar mechanism involved in allergic reactions. That is why exposure to helminths in childhood may prevent allergies. IL-4 creates an autocrine loop that facilitates Th2 development