469308 Enhancing Ex Vivo Platelet Production through Shear Forces within Defined Bioreactors
Through the use of computational fluid dynamic simulations and microfluidic device fabrication, a design – test – build methodology is used to present a dual-flow microfluidic bioreactor system in which aspects of the bone marrow niche are recapitulated to both study the platelet formation process and enhance in vitro yields. Experimental studies are conducted to validate the simulations in terms of streamline profiles and flow patterns with and without cell capture. Microenvironment characteristics include shear profiles and extracellular matrix (ECM) protein coatings. Furthermore, the design of the bioreactor generates uniform shear profiles on Mks and PPLs and allows for exploration of a wide range of physiological shear rates. Our results indicate that our bioreactor design produces 21 ± 3 plts/Mk, and we are currently working to further increase production. Bioreactor-derived platelets are shown to be functional and retain characteristics similar to those of fresh blood platelets. Characterization of the collected platelets from the bioreactor includes surface markers expression, activation in the presence of the thrombin agonist, and morphological/cytoskeletal changes before and after activation. With this microfluidic reactor and further experimental plans, we aim to understand the factors required for initiation of PPL formation to improve in vitro platelet yields.