Rictor deficiency in dendritic cells exacerbates acute kidney injury

Kidney Int. 2018 Nov;94(5):951-963. doi: 10.1016/j.kint.2018.06.010. Epub 2018 Sep 4.

Abstract

Dendritic cells (DCs) are critical initiators of innate immunity in the kidney and orchestrate inflammation following ischemia-reperfusion injury. The role of the mammalian/mechanistic target of rapamycin (mTOR) in the pathophysiology of renal ischemia-reperfusion injury has been characterized. However, the influence of DC-based alterations in mTOR signaling is unknown. To address this, bone marrow-derived mTORC2-deficient (Rictor-/-) DCs underwent hypoxia-reoxygenation and then analysis by flow cytometry. Adoptive transfer of wild-type or Rictor-/- DC to C57BL/6 mice followed by unilateral or bilateral renal ischemia-reperfusion injury (20 min ischemia) was used to assess their in vivo migratory capacity and influence on tissue injury. Age-matched male DC-specific Rictor-/- mice or littermate controls underwent bilateral renal ischemia-reperfusion, followed by assessment of renal function, histopathology, and biomolecular and cell infiltration analysis. Rictor-/- DCs expressed more costimulatory CD80/CD86 but less coinhibitory programmed death ligand 1 (PDL1), a pattern that was enhanced by hypoxia-reoxygenation. They also demonstrated enhanced migration to the injured kidney and induced greater tissue damage. Following ischemia-reperfusion, Rictor-/- DC mice developed higher serum creatinine levels, more severe histological damage, and greater proinflammatory cytokine production compared to littermate controls. Additionally, a greater influx of both neutrophils and T cells was seen in Rictor-/- DC mice, along with CD11c+MHCII+CD11bhiF4/80+ renal DC, that expressed more CD86 but less PDL1. Thus, DC-targeted elimination of Rictor enhances inflammation and migratory responses to the injured kidney, highlighting the regulatory roles of both DCs and Rictor in the pathophysiology of acute kidney injury.

Keywords: Rictor; dendritic cells; kidney ischemia-reperfusion injury.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Kidney Injury / etiology*
  • Animals
  • B7-2 Antigen / analysis
  • Cytokines / genetics
  • Dendritic Cells / physiology*
  • Male
  • Mechanistic Target of Rapamycin Complex 2 / deficiency
  • Mechanistic Target of Rapamycin Complex 2 / physiology*
  • Mice, Inbred C57BL
  • Neutrophil Infiltration
  • Signal Transduction / physiology

Substances

  • B7-2 Antigen
  • Cytokines
  • Mechanistic Target of Rapamycin Complex 2