Suppression of late asthmatic response by low-dose oral administration of interferon-beta in the guinea pig model of asthma.

We investigated the anti-asthmatic effects of low-dose oral and subcutaneous administration of interferon-beta (IFN-beta) on an ovalbumin (OVA)-sensitized and challenged guinea pig model of asthma. Subcutaneous administration of IFN-beta suppressed the eosinophil infiltration by 14.2% of the control and the respiratory resistance (Rrs) by 58.2% at 2.0 MIU/kg. Oral administration of IFN-beta inhibited the late asthmatic response (LAR) by suppressing the increase of Rrs by 29% of the control at 1 IU/ml and the eosinophil infiltration into the trachea and lung by 34.6% at the optimum dosage of 10 IU/ml. Both subcutaneous and oral administration could not inhibit the early asthmatic response (EAR). Additionally we found 2',5'-oligoadenylate synthetase (2',5'-OAS) induction by low-dose oral administration (LDOA) of IFN-beta to the same extent as by subcutaneous administration in whole blood in vivo. These data suggest that LDOA of IFN-beta would have some clinical benefit for patients with asthma.