31 - Converging cell therapy with biomaterials

Abstract

Cell therapies are designed to restore, replace tissue function, or to remove dysfunctional tissues by regulating the presence and function of cell populations. It is found that administering cell therapies with biomaterials may greatly enhance their efficacy due to mechanical and chemical cues delivered by the materials. Synthetic and naturally derived biodegradable materials are often utilized to transplant or locally recruit the specific cell types targeted for therapy, as they mechanically support and guide the function of these cells. Material surfaces can be modified with bioactive peptides to control cellular adhesion, functionality, and subsequent tissue growth. Soluble growth factors and plasmid DNA-encoding bioactive factors and drugs have also been incorporated and delivered from biomaterials to control cellular processes such as migration, adhesion, proliferation, and differentiation. These approaches may be especially important in addressing the widespread loss of viability and function of transplanted cells, as biomaterial-mediated delivery can spatially and temporally maintain control over the transplant microenvironment. Similarly, injecting solutions of growth factors to stimulate various host cell populations has been plagued by the inability to sustain signaling, as these molecules have short half-lives and are susceptible to degradation. Biomaterial delivery may address this challenge by stabilizing these factors and prolonging tissue exposure. The immune response to biomaterials must be characterized in these applications, as it may affect therapeutic signaling to cellular targets through the accumulation of phagocytic cells and inflammatory cytokines, and the up-regulation of specific immune responses is the intention of cancer vaccines and other cellular therapies