Endothelial Progenitor Cells Are Decreased in the Circulation of Patients with Sepsis

Abstract

Background: Acute lung injury (ALI) and sepsis are associated with widespread endothelial injury. Elaboration of endothelial precursor cells from bone marrow that could participate in repair represents one mechanism to attenuate injury.Methods: Blood was obtained from 24 ALI and 12 septic patients within 72 hours of diagnosis. Peripheral blood mononuclear cells were isolated and cultured on fibronectin‐coated wells in endothelial‐specific medium. Numbers of endothelial progenitor colony‐forming units (EPC CFUs) were assessed after 7 days.Results: ALI and sepsis patients were similar for mortality, age, and severity of illness. 81% (9/11) of sepsis patients had septic shock;17% (2/12) had a pulmonary source for sepsis. 54% (13/24) of ALI patients had septic shock. ALI patients had higher EPC CFU numbers than did septic patients [median 56 (19–90) vs 19 (3–50), p<0.04)]. Comparing just patients with septic shock (ALI, n=13 vs. sepsis, n=9) revealed a trend for higher EPC CFUs in ALI patients [median 50 (17–93) vs 19 (11–46), p =0.09). No significant difference in EPC CFU numbers between those with and without septic shock were observed among those with ALI (p=0.58).Conclusions: More numerous EPC CFUs in those with ALI provides evidence for the role of lung injury in their mobilization. Alternatively, septic shock might hinder their release from the marrow.AHA Beginning Grant‐in‐Aid