It should be noted that M2 polarization was not as complete as M1 polarization (Fig. 3e); therefore, LDHC and COX7B2 were downregulated in M2-like macrophages co-cultured with PDA cells likely due to the presence of unpolarized M0 macrophages (Supplementary Fig. 3d). The gene discussed is COX7B2; the disease is Patent ductus arteriosus.