Stromal progenitor cells promote leukocyte migration through production of stromal-derived growth factor 1alpha: a potential mechanism for stromal progenitor cell-mediated enhancement of cellular recruitment to wounds.

摘要

BACKGROUND/PURPOSE: Stromal progenitor cells (SPC) enhance tissue repair in a variety of injury models. However, the mechanisms by which SPCs facilitate tissue repair remain poorly understood. We hypothesized that SPC-enhanced tissue repair is, in part, because of SPC-mediated recruitment of circulating cells to areas of tissue injury. To test this, we examined the migration of leukocytes in response to SPC in vitro. METHODS: Leukocyte migration was assessed in response to SPC, SPC + transforming growth factor (TGF)-beta1, or SPC + AMD3100 using a Transwell assay system (Corning, distributed by Fisher Scientific, Pittsburgh, PA). Supernatants were collected from lower chambers and analyzed for leukocyte content, leukocyte viability, and stromal-derived growth factor (SDF)-1alpha concentration. RESULTS: Stromal progenitor cells increased leukocyte migration compared to media alone (450 +/- 70 vs 112 +/- 17 cells/microL; P .05). SPC treatment with TGF-beta1 resulted in a 36% increase in leukocyte migration and correlated with an increase in SDF-1alpha production. Treatment with AMD3100 resulted in inhibition of leukocyte migration. CONCLUSIONS: Stromal progenitor cells promote leukocyte migration, and this appears to be mediated through SDF-1alpha production. The SPC production of SDF-1alpha may be modulated by other cytokines present in the microenvironment during wound healing. Together, these observations provide a potential mechanism by which SPC may augment healing through enhanced recruitment of inflammatory cells and tissue progenitor cells to areas of tissue injury.