Granulocyte-macrophage colony-stimulating factor (GM-CSF) restores allostimulatory function to accessory cells in patients with AIDS

Background: Impaired allostimulatory function of dendritic cells in patients with AIDS has been reported previously. Granulocyte-macrophage colony-stimulating factor (GM-CSF) can restore the T-cell stimulatory function in transforming growth factor-β1 (TGF-β1)-inhibited murine accessory cells. We now report the effect of intravenous recombinant human GM-CSF (rhGM-CSF) on accessory cells of HIV-infected patients. Method: The in vivo effect of GM-CSF on allostimulatory function of accessory cells was evaluated. Seventeen individuals with AIDS received a single infusion of rhGM-CSF (125 mg/m² over 120 minutes). Samples of peripheral blood lymphocytes (PBL) were taken at 1, 5, and 24 hours after infusion, and the allostimulatory capacity was measured. Results: A single bolus infusion of rhGM-CSF resulted in significantly increased accessory cell function in 13/17 (88%) patients at one or more assayed time points after infusion. Conclusion: These results suggest that the administration of rhGM-CSF can potentially restore allostimulatory function to accessory cells in HIV-infected patients, and this presents a novel way of immune reconstitution. Clinical significance of this approach of immune reconstitution in AIDS patients warrants further investigations.