Abstract: PO0654
Genetic Ablation of CD148 Increases Renal Macrophage Inflammation and Fibrosis in Ureteral Obstructed Kidney
Session Information
- CKD Mechanisms - 2
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2103 CKD (Non-Dialysis): Mechanisms
Authors
- Otsuka, Tadashi, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Takahashi, Keiko, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Narui, Chikage, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Harris, Raymond C., Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Grundmann, Manuel, Bayer AG, Leverkusen, Nordrhein-Westfalen, Germany
- Takahashi, Takamune, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Pasic, Lejla, Vanderbilt University Medical Center, Nashville, Tennessee, United States
Background
CD148 is a transmembrane protein tyrosine phosphatase expressed in several cell types including epithelial, endothelial, and hematopoietic cells. Macrophages express high level of CD148, and its expression is up-regulated by lipopolysaccharide (LPS) which activates innate immune response through toll-like receptor 4. Recently the innate immune system has been recognized as an important modulator of the inflammatory response during infection and tissue injury/repair. However relatively little is known about CD148 function in this cell type and kidney disease model. Here we showed influences of CD148 depletion on unilateral ureteral obstruction (UUO) model and macrophage polarization.
Methods
UUO surgeries were performed in CD148 KO and wild-type (WT) mice on DBA2/J background. Histological and gene expression analysis were performed 3 days and 10 days after UUO to investigate inflammation and fibrosis. Flowcytometry was used to analyze macrophage polarization using CD38/Egr2 method. Primary culture of peritoneal macrophages isolated from these mice were used for in vitro study. After LPS stimulation, inflammatory response (TNFα, IL-1b, IL-6) was quantified by qPCR and ELISA.
Results
CD148KO mice developed more severe renal fibrosis than WT mice at day10. They showed more severe tubular damage compared to WT mice at day3. F4/80 staining revealed increased infiltrated macrophages in outer medulla lesion and flowcytometry showed increased population of inflammatory subtype (M1; CD11b+F4/80+CD38+Egr2-) in CD148KO mice. Although there were no significant differences in whole kidney analysis of inflammatory cytokine qPCR between them, renal macrophages isolated from CD148KO mice showed higher expression of inflammatory cytokine expression (TNFα, IL-1b, IL-6). Peritoneal macrophages derived from CD148KO mice showed higher inflammatory cytokine expression (TNFα, IL-1b, IL-6) to LPS, accompanied by higher phosphorylation of Erk. In addition, Erk inhibitor, U0126 diminished the difference between WT and CD148KO macrophages.
Conclusion
Our data suggests that CD148 negatively regulates macrophage M1 polarization through Erk and its deficiency accelerates macrophage inflammation in UUO kidneys, leading to advanced tubular injury and renal fibrosis.
Funding
- Commercial Support –