production-extracellular-matrix-fibers-via-sacrificial-hollow-fiber

Production of Extracellular Matrix Fibers via Sacrificial Hollow Fiber Membrane Cell Culture

Engineered scaffolds derived from extracellular matrix (ECM) have driven significant interest in medicine for their potential in expediting wound closure ...

University of Arkansas

Biofouling is a persistent problem for membranes exposed to blood or other complex biological fluids, affecting surface structure and hindering performance. In this study, a peptoid with 2-methoxyethyl (NMEG5) side chains was immobilized on polysulfone hollow fiber membranes to prevent protein fouling. The successful attachment of NMEG5 to the polysulfone surface was confirmed by X-ray photoelectron spectroscopy and an increase in hydrophilicity was confirmed by contact angle analysis. The NMEG5-modified surface was found to resist fouling with bovine serum albumin, lysozyme, and adsorbed significantly less fibrinogen as compared with other published low-fouling surfaces. Due to the low fouling nature and increased biocompatibility of the NMEG5 coated membranes, they have potential applicability in numerous biomedical applications including artificial lungs and hemodialysis.

PEG-mimetic peptoid reduces protein fouling of polysulfone hollow fibers.

The therapeutic potential of biological scaffolds as adjuncts to synthetic polymers motivates the engineering of fibers formed using the extracellular matrix (ECM) secreted by cells. To capture the ECM secreted by cells during in vitro culture, a solvent degradable hollow fiber membrane (HFM) was created and utilized as a cell culture platform. NIH/3T3 fibroblasts were injected into the narrow (0.986 ± 0.042 mm) lumina of mesoporous polysulfone HFMs and maintained in culture for up to 3 weeks. Following cell culture, HFMs were dissolved using N-methyl-2-pyrrolidone and the accumulated ECM was collected. The ECM retained the filamentous dimensions of the HFM lumen. The process yielded up to 0.89 ± 0.20 mg of ECM for every mm of HFM dissolved. Immunofluorescence, second-harmonic generation microscopy, and tandem mass spectrometry indicated the presence of an array of ECM constituents, including collagen, fibronectin, and proteoglycans, while FTIR spectra suggested thorough HFM material dissolution. Isolated ECM fibers, although fragile, were amenable to handling and exhibited an average elastic modulus of 34.6 ± 15.3 kPa, ultimate tensile strength of 5.2 ± 2.2 kPa, and elongation-at-break of 29% ± 18%. ECM fibers consisted of an interconnected yet porous (32.7% ± 5.8% open space) network which supported the attachment and in vitro proliferation of mammalian cells. ECM fibers were similarly synthesized using muscle and astrocyte cells, suggesting process robustness across different cell types. Ultimately, these ECM fibers could be utilized as an alternative to synthetics for the manufacture of woven meshes targeting wound healing or regenerative medicine applications.

Cell derived extracellular matrix fibers synthesized using sacrificial hollow fiber membranes.

Unsuccessful recanalization attempts in stroke patients have been associated with fibrin-rich thromboemboli linking retrieval mechanism performance and clot composition. To continue development of stroke retrieval mechanisms, the material properties of cerebral thromboemboli must be replicated; however, current methods for emboli analog formation lack quantitative measurements for both material stiffness and composition of cerebral thromboemboli. This study investigates emboli analog (EA) formation to mimic the material stiffness and composition of cerebral thromboemboli to develop new retrieval mechanisms.

Jamie Hestekin

Ralph E. Martin Department of Biomedical Engineering

University of Arkansas

Production of Extracellular Matrix Fibers via Sacrificial Hollow Fiber Membrane Cell Culture