Spatially Patterned Notch Signaling Through Functionalized Biomaterials: Towards Pre-designed Differentiation Of Embryonic Stem Cells Into Lymphoid Lineages

摘要

Current techniques in embryonic stem cell differentiation have been widely employed to yield lineages of all three germ layers but suffer from the limitations associated with 2D systems and thus, fail to provide the three dimensional framework and the spatial. cues necessary formulticellular differentiation. Our approach in the differentiation of embryonic stem cells involves spatial cues in a three dimensional biodegradable scaffold matrix to direct a single embryonic stem cell population to multiple lymphocyte lineages, namely to B and T lymphocytes. We have hypothesized that in the presence of stromal derived factors (from OP9 murine stromal cells), conjugation of a notch-ligand to biomaterial surfaces would provide the necessary signal for ES cell differentiation into T cells. In the absence of such direct notch signaling, the same ES cells should differentiate into the B lineage. Therefore, by spatially patterning a notch ligand on 2D or 3D biomaterial scaffolds we could direct a single ES cell population into both the T and B cell lineages. Such a study would not only elucidate insights in lymphocyte differentiation, antigen presentation, and T cell-B cell interactions but a better understanding of the effects of biochemical substrates on lymphocyte differentiation, an area not readily characterized in current lymphocyte differentiation approaches. Ultimately, these studies could lead to the engineering of realistic organotypic models of lymphoid systems that can be used in high throughput screening of vaccines and pathogens as well as to study antigen presentation, class switching and cell-cell interactions.