title: 4-D Flow Control in Porous Scaffolds: Toward a Next Generation of Bioreactors.
abstract: Tissue engineering (TE) approaches that involve seeding cells into predetermined tissue scaffolds ignore the complex environment where the material properties are spatially inhomogeneous and evolve over time. We present a new approach for controlling mechanical forces inside bioreactors, which enables spatiotemporal control of flow fields in real time. Our adaptive approach offers the flexibility of dialing-in arbitrary shear stress distributions and adjusting flow field patterns in a scaffold over time in response to cell growth without needing to alter scaffold structure. This is achieved with a multi-inlet bioreactor and a control algorithm with learning capabilities to dynamically solve the inverse problem of computing the inlet pressure distribution required over the multiple inlets to obtain a target flow field. The new method constitutes a new platform for studies of cellular responses to mechanical forces in complex environments and opens potentially transformative possibilities for TE.
authors.forename: Khalid
authors.initials: K
authors.lastname: Youssef
authors.forename: Nanette N
authors.initials: NN
authors.lastname: Jarenwattananon
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Archer
authors.forename: Julia
authors.initials: J
authors.lastname: Mack
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Iruela-Arispe
authors.forename: Louis-S
authors.initials: LS
authors.lastname: Bouchard
mesh_terms: D061249:Batch Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D019149:Bioreactors; D049109:Cell Proliferation / Q000502:physiology; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D040542:Mechanotransduction, Cellular / Q000502:physiology; D044085:Microfluidics / Q000295:instrumentation* / Q000379:methods; D016062:Porosity; D033081:Shear Strength / Q000502:physiology; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000295:instrumentation* / Q000379:methods; D054457:Tissue Scaffolds