IL17A and Patent ductus arteriosus: Th17 cell have been implicated in a variety of inflammatory conditions and are postulated to have a role in many epithelial cancers including PDA.[29]–[31] To determine if a subset of the FOXP3−CD4+ T cells might produce IL-17, we performed intracellular cytokine staining for IL-17 after PMA/ionomycin stimulation.