NGAL release from peripheral blood mononuclear cells protects against acute kidney injury and prevents AKI induced fibrosis

We propose the use of a peripheral blood mononuclear cell therapy based on cell NGAL release to be used in the clinical setting for acute kidney injury (AKI) and the derived fibrosis. First, we designed a procedure whereby PBMC overexpress NGAL and anti-inflammatory agents when subjected to repetitive anoxia/reoxygenation (PBMC (A/R)). Using an in vivo AKI model, we observed that PBMC(A/R) reduces BUN and creatinine levels in blood and inflammation, enhances anti-inflammation, induces proliferation of tubular epithelial cells and re-duces AKI-induced fibrosis. Flow cytometry analysis evidenced that monocytes are the only cells accumulated in the injured kidney and phenotype analysis of freshly isolated kidney macrophages, revealed that the healing phenotype is maintained the time needed for recovery. NGAL release from PBMC(A/R) determines the beneficial effect of the therapy since administration of a NGAL antibody previous to the therapy or injection of PBMC(A/R) obtained from NGAL KO animals abolished the beneficial effects. CD11b-NGAL positive cells were enhanced in tissue after PBMC (A/R) therapy and were produced by the injected monocytes. In an in vitro model with tubular epithelial cells (NRK52e) we proved that NGAL release by PBMC(A/R) induced epithelial proliferation and activation of PI3K/Akt pathway.

Automated summary

This study proposes the use of peripheral blood mononuclear cell therapy based on cell NGAL release for the treatment of acute kidney injury (AKI) and associated fibrosis. The results show that PBMC(A/R) can reduce BUN and creatinine levels, lower inflammation, promote proliferation of tubular epithelial cells, and reduce AKI-induced fibrosis. Moreover, the release of NGAL from PBMC(A/R) plays a crucial role in the beneficial effects of this therapy.