Differential immunostimulating effect of granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF) and interferon gamma (IFNgamma) after severe trauma.

OBJECTIVE: Severe trauma leads to an increased vulnerability to bacterial sepsis. In the present study, we compared the immunostimulating potential of granulocyte-colony stimulating-factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon-gamma (IFN-gamma).
DESIGN: Prospective clinical experimental study.
SETTING: University hospital intensive care unit and research facility. PATIENTS: 6 patients with an Injury Severity Score (ISS) of more than 25 points.
INTERVENTIONS: Heparinized blood samples of severely injured patients and 12 healthy volunteers were incubated in vitro with 10 ng/ml GM-CSF, 10 ng/ml G-CSF or 10 ng/ml IFN-gamma for 6 h. MEASUREMENTS: Flow cytometry: HLA-DR expression on monocytes, B- and T-lymphocytes. ELISA: LPS-induced TNFalpha and IL-10 production.
RESULTS: In all patients reduced cytokine production and HLA-DR expression on monocytes was established. After administration of GM-CSF and IFN-gamma it in vitro, the level of HLA-DR expression on monocytes and the it ex vivo TNFalpha-synthesis increased while only GM-CSF increased significantly IL-10-liberation after LPS-stimulation. However, only IFN-gamma had the capacity to enhance HLA-DR on B- and T-lymphocytes. G-CSF it in vitro had no significant effect on the measured parameter.
CONCLUSIONS: These data suggest that GM-CSF and IFN-gamma may serve to support immune functions in severely injured patients.