Effects of oral administration of interferon-alpha on antibody production in mice with induced tolerance

In vivo systemic effects and the immunomodulating potential of the oral adm inistration of murine interferon-alpha (IFN-alpha) were investigated throug h mRNA expression of both IFN-alpha-inducible factors, interferon regulator y factor-1 (IRF-1) and 2,5-adenylate synthetase [2-5(A) synthetase] and 2-5 (A) synthetase enzymatic activity in spleen and antibody production. The da ily administration of IFN-alpha (0.1, 1, 10, and 100 IU/body) for 1 week au gmented IRF-1 and 2-5(A) synthetase mRNA expression levels, as well as 2-5( A) synthetase enzymatic activity in spleen cells but not in cervical lymph nodes, The in vivo immunomodulating potential of the oral administration of IFN-alpha was also evaluated through antibody production in mice with indu ced tolerance. Ovalbumin (OVA) was administered intraperitoneally (i.p.) to induce systemic antibody production on day 0 when OVA feeding was initiate d. The OVA was fed every 2-3 days for a total of 14 doses to suppress serum antibody levels. Oral administration of murine IFN-alpha was initiated on day 0 and was continued for 5 consecutive days weekly for 5 weeks (24 doses ), On every sampling date (days 10, 17, 24, and 32), specific antibody leve ls in the IFN-alpha-administered groups were significantly higher than thos e in the control (nonadministered) group. This was especially noted in earl y phases (days 10 and 17) of antibody production when the levels of antibod y in serum from the IFN-alpha-administration groups were equivalent to thos e of the nontolerance group. Altogether, it is suggested that oral use of I FN-alpha can elicit immunomodulating actions (e.g., antibody levels) by aff ecting the systemic immune system(s).