SBIR-STTR Award

Since human pluripotent stem cells were first isolated, research on stem cells has received much public attention, because of the extraordinary importance for fundamental studies and the potential of using these cells in numerous clinical applications. Stem cell differentiation is the process by which an unspecialized cell becomes specialized into one of many cell types of the organism, all possessing specific functions. The possibility of manipulating this process in vitro provides opportunities for using isolated stem cells for different therapeutic applications, including stem cell transplantation to treat degenerated or malignant disorders. In vivo maturation and differentiation of hematopoietic cells is regulated by a variety of mechanisms, which include growth factors, chemokines, and cytokines released by accessory cells and, more importantly, by hematopoietic cells themselves. Methods used for monitoring the effectiveness of this process and isolating viable cells of interest are complicated, laborious and time consuming. Using single cell encapsulation technology, immunophenotyping and flow cytometry, this Small Business Innovation Research application proposes to develop a rapid and sensitive method for isolating stem cells of interest for use in various therapeutic applications.

Thesaurus Terms:
cell sorting, flow cytometry, hematopoietic stem cell, phenotype, single cell analysis, stem cell, technology /technique development CD34 molecule, bone marrow, cytokine fluorescent dye /probe, human tissue, tissue /cell culture

In recent years, it has become clear that the majority of cell surface markers are shared by many types of stem and progenitor cells. Thus the ability to separate unique cell sub-populations using current methods is limited. Although it is known that stem cells secrete specific factors into the extracellular space, it is difficult to characterize secretory activity of individual viable cells within a heterogeneous population. Association of the secreted factor(s) with a specific cell type provides an additional marker that can be used to characterize the cell and permit separation of cells while maintaining viability. Combining immunophenotyping with secretory profile is powerful approach for both research and eventual therapeutic applications. Development of new, reliable methods for analyzing and recovering single, viable stem cells based on secretory profile combined with expression of cell surface antigens is of considerable interest. The GMD Stem Cell Assay addresses the need for a functional, multiparameter, single cell assay that does not compromise cell viability, physiological state, and functionality. Phase I research optimized the assay for use with several experimental hematopoietic models. Phase II research will expand use of the assay with other models, including endothelial progenitor cells. This assay format can be widely used for immunological studies, including stem cell research and clinical applications. By providing a reliable method for analyzing and recovering single, viable stem cells based on secretory profile combined with expression of cell surface antigens, this assay format will be useful for stem cell research and clinical applications.

Thesaurus Terms:
cell sorting, cell surface receptor, flow cytometry, immunophenotype, secretory protein, stem cell, technology /technique development CD34 molecule, biomarker, cell differentiation, colony stimulating factor, cytokine, cytotoxicity, gene expression, hematopoietic stem cell, tumor necrosis factor beta cell line