Human interferons active on murine cells induce pulmonary cysts in A2G mice

Suckling A2G mice were injected daily from birth for 8 days with highly purified human lymphoblastoid interferon (IFN) or recombinant interferons-alpha 1 or -alpha 2 rIFN-alpha 1, rIFN-alpha 2), or mouse interferon-alpha/beta (IFN-alpha/beta), or control preparations. Only mouse IFN inhibited the growth of suckling A2G mice and induced liver cell necrosis. At 56 days the mice were killed and the lungs examined for the presence of pulmonary cysts. Human lymphoblastoid IFN and rIFN-alpha 1 (and mouse IFN-alpha/beta), which exhibited significant biological activity on mouse cells in culture, induced pulmonary cysts in A2G mice. rIFN-alpha 2, which showed little or no activity on mouse cells, did not induce pulmonary cysts.