CCR2 and pulmonary fibrosis: Combined with our previous studies, in which myeloid-specific Notch signaling blockade ameliorated murine renal fibrosis and lung fibrosis by regulating CCR2+ monocyte-derived macrophage recruitment (37, 38), we wondered whether the attenuated DA neurodegeneration in RBP-JcKO mice also depended on the reduction in CCR2+ monocyte recruitment.