Abstract
Transformation of human peripheral blood lymphocytes with Epstein-Barr virus and rapid screening on rat insulinoma cells by an enzyme-linked immunosorbent assay were used to identify monoclonal autoantibodies that reacted with human pancreatic islets. Six such monoclonal autoantibodies were isolated and cloned. All six also were found to react with human thyroid. It is concluded that lymphocytes able to make autoantibodies that react with both the pancreas and thyroid are common in the human B cell repertoire.