Rheological and Proteomics Characterization of Thermoresponsive Hydrogel from Porcine Cornea Extracellular Matrix for Corneal Tissue Engineering Purposes

Abstract

Purpose : Fabricating thermoresponsive hydrogels from decellularized tissues is a trending approach to develop novel therapeutic biomaterials for tissue engineering purposes. There are differences in the characteristics of the produced hydrogel related to the source of the tissue as well as the decellularization and solubilization protocols. Detailed characterization of the hydrogels will support the efforts to optimize their application as biomaterials for tissue engineering and therapeutics. Here, we fabricated an in-situ thermoresponsive hydrogel from decellularized porcine cornea extracellular matrix, COMatrix (COrnea Matrix), and characterized its structure and thermoresponsive rheological behavior (heat-induced Sol-Gel transition) as well as exploring its protein composition using proteomic approaches.

Methods : The COMatrix hydrogel was fabricated by decellularization and partial digestion of porcine cornea. The gelation was induced by mild-heat (37°C). The turbidimetric gelation kinetics was evaluated by pre-warmed spectrophotometer. The rheological gelation kinetics and properties of COMatrix was evaluated with a temperature controlled rheometer. The protein composition of COMatrix was mapped using mass spectrometric proteomics.

Results : COMatrix forms a transparent gel (10 minutes gelation time) after in-situ curing with heat, characterized by alteration in light absorbance and rheological indexes. . The highest elastic shear modulus (G’) and highest viscous modulus (G”) for 25 mg/ml hydrogels were 83.3±4.2 Pa and 12.9±7.2 Pa for 25 mg/ml samples. The rheological characterization of heat-formed COMatrix gel shows similar behavior to common biomaterials utilized in tissue engineering. The fibrillar structure of COMatrix gel was observed by scanning electron microscopy as the density of fibers attenuates in lower concentrations. Mass spectrometric proteomic analysis revealed that COMatrix hydrogel is rich in extracellular matrix proteins with known regenerative properties such as lumican, keratocan and laminin in addition to structural collagen proteins.

Conclusions : COMatrix hydrogel is a naturally driven biomaterial with favorable biomechanical properties and protein content with potential application as a therapeutic biomaterial in ocular regeneration and tissue engineering.

This is a 2021 ARVO Annual Meeting abstract.