TSLP and Patent ductus arteriosus: Other proteins secreted by CAFs as messenger to crosstalk with immune cells in PDA include but are not limited to CXCL1 (128), CXCL10 (129), IL-33 (130), ETS2 (131), galectin-1 (132), thymic stromal lymphopoietin (TSLP) (54) and βig-h3 (133).