Monoclonal antibody against myeloid leukemia cell line (KG-1).

A murine monoclonal antibody (WI-5) was produced against a myeloid leukemia cell line (KG-1). The antibody was immunoglobulin G3K. It reacted only against KG-1 cells and failed to react against 33 other cell lines representing fibroblasts, solid tumors, and cells of myeloid and lymphatic origin. It also showed no reaction against normal red blood cells, granulocytes, platelets, monocytes, and T- and B-lymphocytes. Similarly, there was no reaction against lymphocytes transformed by mitogens. Peripheral blood and bone marrow samples from acute granulocytic and acute lymphocytic leukemia, chronic granulocytic leukemia, chronic granulocytic leukemia in blastic crisis, and chronic lymphocytic leukemia failed to react with WI-5. It was suggested that WI-5 detected a unique antigen on KG-1 cells.