Abstract
The 'injury hypothesis' in organ transplantation suggests that ischemia-reperfusion injury is involved in the adaptative alloimmune response. We previously found that a strong immune/inflammatory response was induced by ischemia during kidney transplantation in rats. We show here that immature dendritic cells (DCs) undergo hypoxia-mediated differentiation comparable to allogeneic stimulation. Hypoxia-differentiated DCs overexpress hypoxia inducible factor-1α (HIF-1α) and its downstream target genes, such as vascular endothelial growth factor or glucose transporter-1. Rapamycin attenuated DC differentiation, HIF-1α expression, and its target gene expression in a dose-dependent manner along with downregulated interleukin-10 secretion. Coculture of hypoxia-differentiated DCs with CD3 lymphocytes induced proliferation of lymphocytes, a process also neutralized by rapamycin. Furthermore, in vivo examination of ischemia-reperfusion-injured mouse kidneys showed a clear maturation of resident DCs that was blunted by rapamycin pretreatment. Our results suggest that hypoxia is a central part of the 'injury hypothesis' triggering DC differentiation under hypoxic conditions. Rapamycin attenuates the hypoxic immune-inflammatory response through inhibition of the HIF-1α pathway.
Original language | English |
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Pages (from-to) | 816-825 |
Number of pages | 10 |
Journal | Kidney International |
Volume | 73 |
Issue number | 7 |
DOIs | |
Publication status | Published - Apr 2008 |
Externally published | Yes |
Keywords
- Costimulatory molecules
- Cytokines
- Dendritic cells
- Hypoxia
- mTOR inhibitors