CCR2 and stage 5 chronic kidney disease: As macrophages may influence the pathogenesis of podocytopathy-associated kidney diseases (like primary MGN, where infiltration of CD68+, CCR2+ macrophages has been recognized as a significant indicator of end-stage renal failure [28]), further studies of association between monocyte/macrophage content, origin (infiltrating vs. resident), activation profiles (M1—proinflammatory vs. M2—alternatively activated) and CD73 expression in human kidney disease are necessary to check the accordance of our results with previous data from murine models.