Effect of human amnion-derived multipotent progenitor cells on hematopoietic recovery after total body irradiation in C57BL/6 mice

Background: the hematopoietic system is sensitive to the adverse effects ofionizing radiation. cellular therapies utilizing mesenchymal stem cells or vascularendothelial cells have been explored as potential countermeasures for radiationhematopoietic injuries. we investigated cells cultured from amnion(amnion-derived multipotent progenitor cells, amps) for effects on hematopoieticrecovery following total body irradiation in mice. materials and methods:c57bl/6j mice were sham-irradiated or exposed to ^60co irradiation (7.75 – 7.90 gy,0.6 gy/min). either amps (5 × 10^6 cells/animal) or vehicle were administered 24 hpostirradiation via intraperitoneal injection. results: we observed a 13% and20% improvement in 30-day survival of mice treated with amps comparedwith treatment with vehicle following irradiation at 7.75 and 7.90 gy,respectively. amp treatment was characterized by a trend toward acceleratedrecovery of white blood cells, neutrophils, reticulocytes, and monocytes,measured through day 40 postirradiation after 7.75 gy. amp treatmentenhanced hematopoietic cell repopulation of spleen and femoral bonemarrow as measured by total nucleated cell and hematopoietic progenitorcell counts in comparison to vehicle-treated animals. facs analysis showedthat amps treatment significantly mitigated the reduction in cd11b^+/gr-1^intand cd11b^+/gr-1^high bone marrow cell populations at the nadir, and improvedrecovery of these cell types. conclusion: together, our data indicate that ampsreduced hematopoietic toxicity induced by ionizing radiation when infused within24 h a9er radiation injury.