REDUCED INTERFERON-ALPHA PRODUCTION BY EPSTEIN-BARR-VIRUS TRANSFORMEDB-LYMPHOBLASTOID CELL-LINES AND LECTIN-STIMULATED LYMPHOCYTES IN CONGENITAL DYSERYTHROPOIETIC ANEMIA TYPE-I

The concentrations of interferon-alpha (IFN-alpha) in supernatants fro m cultures of Epstein-Barr virus (EBV) transformed B-lymphoblastoid ce ll lines derived from seven patients with congenital dyserythropoietic anaemia (CDA) type I were below the 95% confidence limits for those d erived from six healthy subjects. In contrast, the concentrations of I FN-alpha in supernatants from cultures of EBV-transformed lymphoblasto id cell lines derived From four patients with other types of CDA and f our patients with hereditary sideroblastic anaemia were normal. Supern atants from cultures of peripheral blood lymphocytes stimulated with p hytohaemagglutinin or pokeweed mitogen contained less IFN-alpha when t he cells were derived from patients with CDA type I than when derived from healthy subjects. Since patients with CDA type I show a substanti al haematological response to treatment with IFN-alpha, the data sugge st that impaired IFN-alpha production may be an important pathogenetic mechanism in CDA type I.