The role of interferon alpha/beta in the induction of intestinal pathology in mice.

We have investigated the role of interferon-alpha/beta (IFN-alpha/beta) and IFN-dependent effector cells in causing enteropathy in mice. The IFN-inducer polyinosinic:polycytydylic acid (poly I:C) augmented the natural killer (NK) cell activation normally seen in neonatal (CBA x BALB/c)F1 mice with graft-versus-host reaction (GVHR) and exacerbated the systemic and intestinal consequences of GVHR. Poly I:C itself produced a similar pattern of intestinal pathology when administered to normal mice. The effects of poly I:C on NK cell activity and intestinal architecture in normal mice could be reproduced by a single injection of purified IFN-alpha/beta and the intestinal lesions caused by IFN-alpha/beta were prevented by in vivo depletion of NK cells with anti-asialo GM1. These results indicate that IFN-alpha/beta may play an important role in immunologically mediated enteropathies by virtue of its ability to activate NK cells.