ORAL-MUCOSAL ADMINISTRATION OF IFN-ALPHA POTENTIATES IMMUNE-RESPONSE IN MICE

We studied the effects of oral-mucosal administration of murine interf eron-alpha (Mu-IFN-alpha) on immune responses and infection with vacci nia virus (VV) in mice. When Mu-IFN-alpha was administered to sheep re d blood cell (SRBC)-sensitized mice for 4 or 5 days, Mu-IFN-alpha sign ificantly enhanced delayed-type hypersensitivity (DTH) and antibody pr oduction, with maximum enhancement of each at 1 IU/body, To investigat e the antiviral effect of oral-mucosal Mu-IFN-alpha, mice were infecte d with VV, and Mu-IFN-alpha was administered for 15 days. Pocks were o bserved in the tail skin of infected mice, and Mu-IFN-alpha at doses o f 1, 10, and 100 IU/body significantly suppressed pock formation. Also , VV-specific cytotoxic T cells (CTL) were observed in the spleen from the same mice at 7 days after infection, and Mu-IFN-alpha enhanced CT L activity at doses above 1 IU/body. These results suggest that the or al-mucosal Mu-IFN-alpha may have potentiating effects on cellular and humoral immune responses, which may contribute to its effects against VV.