This proposal specifically aims to produce and characterize polyclonal antisera to the newly discovered 9804 antigen for assessing the potential value of this molecule in isolating human hematopoietic stem cells (HSC). Important for this characterization is an understanding of the gene (or gene family) that encodes the 9804 protein; therefore, the project also seeks to define the nature of the 9804 cDNA in human bone marrow tissue. This work will use existing and recently developed immunological techniques, in addition to standard molecular biological techniques, to meet the project goals. The long term objective of this proposal is to enhance current HSC isolation procedures through the provision of monoclonal antibodies that exclusively recognize cells capable of long term reconstitution of the hematopoietic system. The use of bone marrow transplant for the treatment of the malignant diseases is demonstrated in certain clinical situations; however, the paucity of stem cell exclusive reagent limits the use of therapeutic procedures that require or would benefit from these cell populations.
