Production of sheep polyclonal antibodies against the 2'-5' oligoadenylate synthetases

A 20-amino acid peptide corresponding to a common part of the 40 and 46 kD forms of human 2'-5' oligoadenylate synthetase was coupled to keyole lymphet haemocyanin (KLH) and used as immunogen in sheep. After a cycle of four immunizations, immunoglobulins able to recognize the 20-amino acid peptide as evaluated in ELISA assays were purified by an immunoadsorbent with the peptide immobilized on Sepharose CL-4B and used in Western blot employing a secondary anti-sheep antibodies and iodinated protein A as indicator system. Results obtained using extracts from human and mouse cells treated for 15 hr with IFN-alpha as antigen demonstrated that the anti-peptide antibodies recognize several forms of the 2'-5' oligoadenylate synthetase enzyme complex. These antibodies therefore represent a useful tool for monitoring the induction of the above enzymes.