THE EFFECT OF INTERFERON-GAMMA ON REJECTION AND NEUTROPHIL FUNCTION FOLLOWING TRANSPLANTATION

Rats were used as a model for a living heterotopic cardiac allograft o rgan transplant. Rats treated in this model with recombinant rat inter feron-gamma (IFN-gamma) showed accelerated rejection in a dose-depende nt fashion. However, rats treated with maintenance doses of cyclospori ne and IFN-gamma expressed increased rejection at 20 days that had res olved completely by 45 days post-transplantation. Polymorphonuclear le ukocytes (neutrophils) were isolated from the blood of rats, and their function was determined by treating the cells with f-Met-Leu-Phe (FML P) and measuring superoxide produced. Results indicate that the neutro phils from rats treated with maintenance doses of cyclosporine and IFN -gamma still had increased IFN-gamma-modulated fMLP-induced respirator y burst and that maintenance cyclosporine therapy can inhibit the IFN- gamma-mediated accelerated rejection without compromising the antimicr obial effects of IFN-gamma treatment.