In Vitro Constitution of Esophageal Muscle Tissue with Endocyclic and Exolongitudinal Patterns

Abstract

Smooth muscle tissue is the main functional structure of the esophagus and comprises of the endocircular and exolongitudinal muscle layers. To construct a tissue engineered smooth muscle by mimicking the esophageal muscle tissue, we have designed a silicon wafer where a daughter mold was prepared using soft PDMS. The daughter mold was, in turn, casted with poly(ester urethane) (PU) solution to fabricate the tissue scaffolds. The casted PU scaffolds were available in two configurations. Prototype 1 (P1) have microchannels of 100 μm width and discontinuous channel wall with gaps of 30 μm at regular intervals. Prototype 2 (P2) have microchannels of 200 μm width and continuous channel walls. The wall thickness and depth of the microchannels are 30 μm. A tubular scaffold with micropattern P1 in the lumen and micropattern P2 on the exterior was fabricated with the aim of regenerating muscle tissue with endocircular and exolongitudinal muscle architecture. After grafting with natural silk fibroin (SF), the PU micropatterned scaffold demonstrated the ability to promote smooth muscle cell (SMC) growth and differentiation; differentiation is believed to contribute to maintain the contractile function of SMCs. Results from the preliminary in vivo test revealed that the tubular scaffold patterned with microchannels is capable of supporting esophageal muscle regeneration.

Biocompatible surgical meshes based on decellularized human amniotic membrane

“…This is the motivation for us to select PU as the physical support to offer the mechanical strength while the biocompatibility from dHAM was maintained. The not bad cytocompatibility of PU material has repeatedly proved in our previous work [20][21][22].…”

“…Primary smooth muscle cells (SMCs) were digested and proliferated from rabbit esophagus [20]. Membranes of dHAM/PU and PU were punched into a disc with the diameter of 6.4 mm.…”

“…In order to settle the HAM's problems like over-softness and weak mechanical properties, poly(ester urethane) (PU) was selected as physical support because of PU's non-toxicity and biodegradability with good mechanical properties like strength, elasticity and stability, which was much proved in our previous studies or other's work [20][21][22][23][24]. Decellularized HAM (dHAM) was expected to provide biocompatibility while PU provided physical strength.…”

Constitution and in vivo test of micro-porous tubular scaffold for esophageal tissue engineering

“…Zhu et al have synthesized biodegradable matrices, developed scaffold fabrications and modifications to setup a biocompatible interface between living cell/tissue and materials, aiming at constructing esophageal substitutes with good biocompatibility, cytocompatibility, biodegradability, and mechanical properties. [14][15][16][17][18][19] Along the line of developing biodegradable polymeric scaffold with defined shape and micro-pore structure, this current work focuses on the interface functionalization of the poly(L-lactide-co-caprolactone) (PLLC) porous scaffold, because surface epithelialization has been considered to be the most important way to provide bio-functional epithelium, the functionalized component of tissue-engineered esophagus. 20 In our previous studies, the ECs contained in mucosal layer were supported by basement membrane (BM) which is a thin layer (thickness of 86 AE 15 nm) of acellular tissue consisting of interwoven fibers with mean diameter of 66 AE 24 nm (range 28-165 nm) and containing collagen IV, laminin, entactin, and proteoglycans.…”

Electroresponsive Aqueous Silk Protein As “Smart” Mechanical Damping Fluid

“…Silk polymers have been studied for a broad range of biomedical and engineering applications because of the distinctive properties they possess in the crystallized state. 5−7 More recently, the unique chemical properties of uncrystallized aqueous silk solutions have been identified. 8−10 …”