The overall objective of this proposal is to develop a clinical-grade Megakaryocyte Development Medium (MDM) that supports the ex vivo development of human megakaryocytes. Use of this unique medium will provide information on several critical gap-areas concerning these elusive yet critically important cells; lipid metabolism, regulation of maturation, and clinical utility. The innovative aspects are the studies on enhancing lipid metabolism, the use of cytokine/matrix molecule combinations, and an in vivo megakaryocyte-transplantation model. MDM will have clinical use in developing therapies for thrombocytopenia and other platelet disorders, in that it allows generation of large numbers of megakaryocytes (> 10/9) that are not possible via routine bone marrow aspiration. MDM also allows for the standardization of megakaryocyte culture conditions between laboratories. Building on the successful results of our Phase I studies, we have designed relevant and highly critical experiments in our Phase II proposal to investigate the following goals.
Specific Aim 1 addresses the further optimization of MDM, with a particular focus on enhancing megakaryocyte lipid metabolism.
Specific Aim 2 examines the effects of specific cytokines and matrix molecules as complex regulatory signals.
Specific Aim 3 is to test and/or long-term engraftment.
This aim also provides a pre-clinical animal model for cellular-based therapies of platelet disorders.
Specific Aim 4 is to scale these cultures up to levels producing 1-5 x 10/9 megakaryocytes per culture. Successful completion of this Phase II proposal will result in a widely used commercial product, a clinically relevant animal model, and much needed information to further our studies on the development of these biologically important cells.
The development of clinical grade reagents that will support megakaryocyte proliferation and differentiation will be valuable in developing novel approaches for the treatment of hematopoietic disorders such as thrombocytopenia.