Antisera prepared against papain-digested spleen cell membranes were known to by cytotoxic for normal and neoplastic human B lymphocytes and for a majority of acute and chronic myeloid leukemic cells. It is now shown that these antisera are also cytotoxic for normal myeloid stem cells (CFU-C), thus providing a probable explanation for their occurrence in myeloid neoplasia.

This content is only available as a PDF.