The present invention relates to a CD43 epitope expressed on human acute leukemia and lymphoblastic lymphoma cells and its use. More particularly, the present invention relates to a CD43 epitope expressed on human acute leukemia, lymphoblastic lymphoma cells, but not on mature hematopoietic cells, hematopoietic stem cells and non-hematopoietic cells, and to its diagnostic and therapeutic application on acute leukemia and lymphoblastic lymphoma.
