Abstract: SA-PO178
Glutamine Blockade After Severe AKI Reduces Kidney Fibrosis by T-Cell Metabolic Reprogramming
Session Information
- AKI: Mechanisms - III
November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
Authors
- Lee, Kyungho, Johns Hopkins University School of Medicine, Baltimore, United States
- Patel, Shishir Kumar, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Gharaie, Sepideh, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Newman-Rivera, Andrea M., Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Arend, Lois J., Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Noel, Sanjeev, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Slusher, Barbara S., Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Rabb, Hamid, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
Background
Metabolism regulates T cell function, and metabolic reprogramming by glutamine antagonism was previously demonstrated to reduce early injury in AKI. Given that T cells also mediate organ repair, we studied the effects of glutamine blockade on AKI repair and fibrosis.
Methods
Severe AKI was induced with 45 min unilateral ischemia in C57B6 mice. The glutamine antagonist, JHU083, was administered starting 24h after reperfusion. Kidneys were collected at 4 weeks and stained with Masson’s trichrome. Kidney T cells were studied using spectral flow cytometry and machine learning-based analyses.
Results
Glutamine blockade by JHU083 reduced kidney fibrosis in both cortex (21.2±4.2 vs 4.0±0.6%, P=0.001) and medulla (17.3±3.2 vs 9.2±1.4%, P=0.038) compared to vehicle treatment (n=8 /each group). Unbiased high-dimensional analyses segregated T cells from JHU083-treated and vehicle groups. JHU083 increased double-negative (DN) T cells (CD4- CD8-), which have anti-inflammatory properties (6.3±0.7 vs 23.4±1.6% of αβT cells, P<.001, 2.2±0.3 vs 3.0±0.2 ×10^5 cells/g kidney, P=0.035) and naïve CD4 T cells (1.1±0.1 vs 12.8±2.2%, P<.001, 2.2±0.2 vs 6.3±0.7 ×10^4 cells/g kidney, P<.001), whereas effector-memory CD4 T cells decreased (92.8±0.8 vs 75.9±3.5%, P<.001, 1.8±0.1 vs 0.4±0.1 ×10^6 cells/g kidney, P<.001). JHU083 reduced CD4 T cell activation and proliferation (Ki67 94.2±0.5 vs 76.0±3.3%, P<.001; CD69 87.9±0.9 vs 77.2±1.8%, P<.001) as well as CD8 T cells (Ki67 93.5±0.5 vs 80.8±2.6%, P<.001; CD69 97.5±0.2 vs 94.2±0.6%, P<.001). JHU083 downregulated hexokinase II (normalized MFI, CD4 0.49±0.04 vs 0.18±0.04, P<.001; CD8 0.42±0.03 vs 0.27±0.04, P=.021), CPT1a (CD4 0.74±0.07 vs 0.13±0.03, P<.001; CD8 0.72±0.08 vs 0.27±0.04, P<.001), VDAC1 (CD4 0.73±0.08 vs 0.13±0.05, P<.001; CD8 0.77±0.07 vs 0.23±0.05, P<.001), and mTOR expression (CD4 0.58±0.04 vs 0.30±0.02 P<.001; CD8 0.29±0.03 vs 0.09±0.02, P<.001), but upregulated Tomm20 (CD4 0.16±0.04 vs 0.47±0.03, P<.001; CD8 0.28±0.05 vs 0.83±0.04, P<.001).
Conclusion
Reconstitution of T cell metabolism by glutamine blockade after severe AKI reduced kidney fibrosis, increased kidney DN T cells and decreased effector CD4 T cell activation. This is a novel approach to potentially mitigating AKI to CKD, as well as other causes of CKD progression.
Funding
- NIDDK Support