Natural autoantibodies to interferons

Natural antibodies that appear to have arisen in the absence of direct antigenic stimulation often are present in the circulation. In healthy individuals, they are of low prevalence and generally show low affinity to their respective antigens, whereas in autoimmune disease, their frequency and affinity toward specific antigens are in many cases increased. In some autoimmune disease, the spontaneous occurrence of autoantibodies to antigens that are apparently unrelated to symptoms or pathology has been observed. For example, antibodies to interferon-alpha (IFN-alpha) have been observed in patients with systemic lupus erythematosus but appear to be of no clinical significance. Natural autoantibodies to IFN-alpha have also been found in other patients, including those with insulin-dependent diabetes mellitus, heart disease, or cancer and patients who have just received allogeneic bone marrow transplantation. A major property of IFN-alpha autoantibodies is their capacity to both bind to and neutralize the biologic activity of a range of IFN-alpha subtypes and natural IFN-alpha preparations. Their origins and significance remain a matter for debate.