Cell-laden Polymeric Microspheres for Biomedical Applications

Polymers for cell-laden microspheres are discussed. Fabrication techniques and key parameters regarding cell-laden microspheres for specific applications are explored. Several uses of cell-laden microspheres (in vitro production of cells and biomolecules, as well as in vivo delivery of cells for tissue regeneration or therapeutic biomolecule secretion on-site) are discussed and summarized. Microsphere technology serves as an efficient and effective platform for cell applications (in vitro cell culture and in vivo cell delivery) due to its mimicry of the 3D native environment, high surface area:volume ratio, and ability to isolate the entrapped cells from the environment. Properties of cell-laden microspheres are determined by the type of application and the cell. While high cell densities are preferable for large-scale therapeutic biomolecule production in vitro, an immunoprotective barrier is most important for allogeneic pancreatic islet transplantation into patients. Furthermore, the biological cells require a suitable microenvironment in terms of its physical and biochemical properties. Here, we discuss applications of cell-laden microspheres and their corresponding design parameters. Microsphere technology serves as an efficient and effective platform for cell applications (in vitro cell culture and in vivo cell delivery) due to its mimicry of the 3D native environment, high surface area:volume ratio, and ability to isolate the entrapped cells from the environment. Properties of cell-laden microspheres are determined by the type of application and the cell. While high cell densities are preferable for large-scale therapeutic biomolecule production in vitro, an immunoprotective barrier is most important for allogeneic pancreatic islet transplantation into patients. Furthermore, the biological cells require a suitable microenvironment in terms of its physical and biochemical properties. Here, we discuss applications of cell-laden microspheres and their corresponding design parameters. transplantable product that is sourced from a different individual, but of the same species. a homeostatic process in ADCs to undergo programmed cell death (apoptosis) when there is insufficient, inappropriate, or no adhesion to a substrate. This mechanism is the innate switch of a cell to undergo apoptosis upon detachment so as to avert dysplastic proliferation, a key step in tumor formation and metastasis. cells that require extensive adhesion to a substrate and exhibit a spreading morphology; includes most cell types, including endothelial, neuronal, and muscle cells. the process of cells losing their typical morphology and their cell-specific functions when cultured in a monolayer long-term. the process of stem cells changing to a downstream, specialized cell type. end-stage inflammatory response characterized by fusion of macrophages on a biomaterial surface and fibrous capsule formation as part of wound healing. the ability of a compound to induce a humoral (antibody-mediated) or cell-mediated immune response a host response towards the implanted material that leads to immune cell activation and production of cytokines. the temperature below which the polymer changes from a gel into a solution. a microcarrier that contains large pores, allowing cells to penetrate and settle inside it. a microsphere that has a protective capsule over its encapsulated biological cells or drugs. a microsphere that presents cells or drugs on its surface. The microsphere is usually fabricated before seeding of cells. cells that do not require (extensive) adhesion to survive and typically have a rounded morphology. They may be colony forming in soft substrates (e.g., chondrocytes and pluripotent stem cells) or in suspension cultures typically comprising cells of the hematopoietic lineage. an amphiphilic molecule (contains a hydrophilic end and a hydrophobic end) that inserts between two immiscible phases of an emulsion, thereby lowering the interfacial tension and stabilizing the emulsion. transplantable product that is sourced from a different species.