"RECONSTRUCTION OF FUNCTIONAL GRADIENTS USING MELT ELECTROWRITING
Frendion F.S.J. Marchena1,2, Magdalena Gladysz1,3, Malgorzata K. Wlodarczyk-Biegun1,4
1Polymer Science - Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
2Hanze University of Applied Science in Groningen, Zernikeplein 7, 9747 AS Groningen, The Netherlands
3Pharmaceutical Analysis, Groningen Research Institute of Pharmacy, University of Groningen, Deusinglaan 2, 9713 AW Groningen, The Netherlands
4Biofabrication and Bio-Instructive Materials, Biotechnology Center, The Silesian University of Technology, B. Krzywoustego 8, 44-100 Gliwice, Poland
Melt Electrowriting (MEW) is a biofabrication approach that combines principles of electrospinning and 3D printing. It allows obtaining the porous scaffolds with well-defined fibers in the range of a few micrometers with unprecedented precision. In our group, we use this approach to reconstruct the structure of different native tissues and model their functions in vitro.
This project aims to develop a functional reconstruction of human trabecular meshwork (HTM). HTM is a mesh located in the eye, responsible for the drainage of liquid for the anterior chamber and, therefore, maintaining the proper pressure in the eye. When dysfunctional, it often leads to glaucoma development.
Different designs of porous scaffolds, closely mimicking the structure of native HTM, were designed and printed using MEW. Polycaprolactone was used for printing, and the scaffolds were coated with poly-L-lysine for cell culture studies. Primary HTM cells were seeded, and their performance was characterized in 21-days culture. Mechanical properties of the scaffolds were analyzed in tensile testing and tuned to obtain values matching healthy and glaucomatous eyes. To analyze the functionality of the proposed models, the permeability test was performed on cell-seeded scaffolds at the physiological liquid pressure.
The scaffolds with the architectures resembling three distinctive zones of native HTM were successfully obtained. HTM cells cultured on the prints revealed high viability and expression of cell-specific proteins. Tensile test results revealed that mechanical properties close to healthy or glaucomatous tissue could be obtained by varying the scaffolds’ design. Cell-seeded scaffolds showed permeability values relevant for native tissue.
The MEW approach allowed to obtain structures closely mimicking native HTM regarding the design, mechanical properties, and function (i.e., permeability). We envision that these scaffolds will find applications as in vitro testing platforms for glaucoma drugs and, after further optimization, as implants for patients that require removal of dysfunctional HTM. This is an especially impactful finding as adequate HTM in vitro models, and biomimetic HTM implants are currently missing.