In vivo effects of recombinant-interferon-beta(1b) treatment on polymorphonuclear cell and monocyte functions and on T-cell-mediated antibacterial activity in patients with relapsing-remitting multiple sclerosis

Treatment with Interferon (IFN)-beta has been proposed as a therapeutic app roach in multiple sclerosis (MS) patients, mostly in view of its immunomodu lating actions. At the same time, evidence has been provided that MS patien ts exhibit polymorphonuclear cell (PMN) deficits, which can explain the inc reased susceptibility to infections in these subjects. Here, in 28 patients with relapsing-remitting (RR) MS under treatment with recombinant (r)-IFN- beta PMN polarization and PMN and monocyte (MO) phagocytosis and killing, a s well as T-cell mediated antibacterial activity, were evaluated before tre atment and over a period of nine months of treatment. Our results point out an enhanced rate of polarization (both "spontaneous" or N-formyl-methionyl-leucyl-phenylalanine-induced) in MS patients. After r -IFN-beta(1b) treatment the polarization rate was further increased. On the contrary, PMN and MO phagocytosis and killing were depressed in comparison to controls and values were further reduced by r-IFN-beta(1b) treatment. In patients T-cell mediated antibacterial activity was decreased at T0 and dramatically dropped in the course of r-IFN-beta(1b) therapy.