The Development of Porcine Acellular Muscle Matrix Hydrogel for Use as a Bio-Ink in 3D Bioprinting

Printable biomaterials (bio-inks) for 3D bioprinters are often expensive and can be difficult to manufacture. Bio-inks suitable for 3D bioprinting are typically biocompatible gels that are both thin enough to be extruded from the print head at low pressures and capable of holding their shape after extrusion. The ability to hold shape can be an intrinsic property of the bio-ink, or it can be achieved immediately after extrusion of the material via various crosslinking strategies and/or with the use of support materials. Here, we describe the development of a novel bio-ink from porcine skeletal muscle. Porcine longissimus dorsi is large and lean muscle that is relatively inexpensive and easy to acquire. Our lab has previously decellularized tissue from this muscle into a solid material called Porcine Acellular Muscle Matrix (PAMM) and shown that PAMM scaffolds can be recellularized with different cell populations. To produce PAMM bio-ink, tissue was processed into thin slices, decellularized, lyophilized, and ground into a fine powder. PAMM powder was then digested with the enzyme pepsin under acidic conditions, which breaks apart the components of the tissue’s extracellular matrix. After neutralization of the resulting solution and raising the temperature, a hydrogel of PAMM was formed. Our next step is to seed cells into PAMM hydrogel to determine its viability as a three-dimensional cell culture/delivery platform. Subsequent research will focus on optimizing the hydrogel for use as PAMM bio-ink in 3D bioprinting applications