Glomerular inflammation and podocyte loss are the hallmarks of chronic kidney disease (CKD) progression. Understanding how podocytes and their microenvironment regulate inflammation is critical for developing effective therapies. In this study, we identified C-C chemokine ligand 5 (CCL5) as an inflammatory mediator elevated in injured podocytes, based on analyses of both human kidney biopsies and mouse models of CKD. We discovered that CCL5 exerts paradoxical effects in nephropathy; while it protects podocytes in vitro, it exacerbates glomerular injury in vivo. Recombinant CCL5 and podocyte-specific CCL5 overexpression promoted cell survival and reduced apoptosis in cultured podocytes. However, in adriamycin-induced nephropathy, CCL5 worsened glomerular injury, increasing proteinuria, glomerulosclerosis, and podocyte loss. Bone marrow (BM) transplantation experiments revealed that CCL5 in BM-derived cells — not kidney-resident cells — drove disease progression. CCL5 deficiency in BM-derived cells conferred protection by increasing reparative M2 macrophages, whereas endogenous CCL5 promoted M1 polarization, inhibited M2 differentiation, and triggered M2-to-M1 transition. These findings demonstrate that while CCL5 supports podocyte survival, its expression in BM-derived cells promotes inflammatory macrophage phenotypes and glomerular injury. The harmful immune effects of CCL5 in BM-derived cells outweigh its podocyte-protective role, highlighting the importance of cell-targeted strategies to mitigate kidney damage.
Ika N. Kadariswantiningsih, Issei Okunaga, Kaho Yamasaki, Maulana A. Empitu, Hiroyuki Yamada, Shin-ichi Makino, Akitsu Hotta, Hideo Yagita, Masashi Aizawa, Ryo Koyama-Nasu, Motoko Y. Kimura, Narihito Tatsumoto, Katsuhiko Asanuma
This file is in Adobe Acrobat (PDF) format. If you have not installed and configured the Adobe Acrobat Reader on your system.
PDFs are designed to be printed out and read, but if you prefer to read them online, you may find it easier if you increase the view size to 125%.
Many versions of the free Acrobat Reader do not allow Save. You must instead save the PDF from the JCI Online page you downloaded it from. PC users: Right-click on the Download link and choose the option that says something like "Save Link As...". Mac users should hold the mouse button down on the link to get these same options.