IL33 and endometriosis: Because we observed elevated ILC2s in the PF of patients with endometriosis and elevated ILC2s in IL-33–treated mice, and because the increase in ST2+ cells was solely due to the increase in ILC2s, we sought to determine if the inflammation, lesion proliferation, neuroangiogenesis, and fibrosis were dependent on ILC2s or if ILC2s were simply a bystander.