Abstract: | A noncytotoxic monoclonal antibody (IgM) HAE9 that selectively binds to 36% CFU-E and more than 90% nucleated erythroid cells in human bone marrow is described. This antibody recognizes a 70-kDa-membrane protein. It is suggested that HAE9 is directed to a human epitope of Ag-Eb, an interspecies mammalian erythroid-specific cell surface marker. |