Monoclonal antibodies: new diagnostic and therapeutic means in acute leukaemias.

The monoclonal antibodies have had a major role in the recent years' development of the diagnostic methods of acute leukaemia. It was by means of these antibodies that the exact mechanism of the differentiation of the different cell lines could be learned a new therapy- and prognosis-orientated leukaemic classifications could be worked out. With the reasonable application of the monoclonal antibodies in more than 99% of the cases the cell line-age and maturity of the dominant cell type of acute leukaemia may be identified today even in cases of aberrant antigen expression. By means of these antibodies clinical relapse may be forecasted in certain cases and minimal residual disease may be demonstrated as well. The therapeutic systemic application of the monoclonal antibodies has yielded only temporary results but in case of bone marrow transplantation their in vitro application is promising since they are capable of eliminating both the T cells and the residual leukaemic cells of the transplant and, as a result, have a role in the prevention of the development of "graft versus host" disease and leukaemic relapse. Monoclonal antibodies are used in acute leukaemia as a routine diagnostic method while their therapeutic application is still at an early stage of investigation.