CD103+ Dendritic Cells Elicit CD8+ T Cell Responses to Accelerate Kidney Injury in Adriamycin Nephropathy

CD103(+) dendritic cells (DCs) in nonlymphoid organs exhibit two main functions: maintaining tolerance by induction of regulatory T cells and protecting against tissue infection through cross-presentation of foreign antigens to CD8(+) T cells. However, the role of CD103(+) DCs in kidney disease is unknown. In this study, we show that CD103(+) DCs are one of four subpopulations of renal mononuclear phagocytes in normal kidneys. CD103(+) DCs expressed DC-specific surface markers, transcription factors, and growth factor receptors and were found in the kidney cortex but not in the medulla. The number of kidney CD103(+) DCs was significantly higher in mice with adriamycin nephropathy (AN) than in normal mice, and depletion of CD103(+) DCs attenuated kidney injury in AN mice. In vitro, kidney CD103(+) DCs preferentially primed CD8(+) T cells and did not directly induce tubular epithelial cell apoptosis. Adoptive transfer of CD8(+) T cells significantly exacerbated kidney injury in AN SCID mice, whereas depletion of CD103(+) DCs in these mice impaired activation and proliferation of transfused CD8(+) T cells and prevented the exacerbation of kidney injury associated with this transfusion. In conclusion, kidney CD103(+) DCs display a pathogenic role in murine CKD via activation of CD8(+) T cells.