MRC1 and Patent ductus arteriosus: Concomitantly with this behavior, in primary tumors, total myeloid cells, F4/80+ macrophages, CD206+ immunosuppressive TAMs, MDSCs, which are robustly immunosuppressive in PDA (18), and neutrophils were all significantly decreased, while numbers of CD8+ T cells were concurrently significantly increased (Figure 5, C–F, and Figure 6, A and B).