Evaluating the Effect of Tissue Selection on the Characteristics of Extracellular Matrix Hydrogels from Decellularized Porcine Bladders

Abstract

Porcine urinary bladder is one of the most used organs to fabricate extracellular matrix (ECM) hydrogel. Although there are two different ECM types inside a bladder, i.e., urinary bladder matrix (UBM) and a subtype ECM (sECM), most studies have only employed UBM for hydrogel fabrication, and overlooked the potential use of sECM. In another aspect, the delamination of UBM from bladders is a time-consuming process; consequently, the use of the whole bladder (WB) will likely increase production yield. Therefore, the objective of this study was to fabricate hydrogels from sECM and WB and compare them to UBM. The results indicated that different layers of the bladder shared almost the same biochemical composition. In terms of gelation kinetics, rheology and morphology, although hydrogels from UBM and sECM exhibited some discrepancies, those from UBM and WB interestingly possessed almost the same characteristics. In in vitro studies, all the hydrogels possessed nearly the same biochemical effects towards L929 viability and C2C12 differentiation. These results could preliminarily indicate that the use of sECM should no longer be ignored, and WB could be a promising substitution for UBM hydrogels, eliminating the need for time-consuming delamination processes, as well as increasing the possibility of mass production.

Investigating the Immunomodulatory Potential of Dental Pulp Stem Cell Cultured on Decellularized Bladder Hydrogel towards Macrophage Response In Vitro

“…DNA fragments were also less than 100 base pairs in length using an electrophoresis test ( Figure 1 ). The results were in accordance with our previous studies [ 20 ], confirming the stability of the decellularization procedure.…”

“…Although the exact mechanism for the ECM hydrogel formation process is not fully understand, it is commonly thought that it involves the self-assembly process of collagen under appropriate physiological condition of 37 °C and pH 7.4, regulated in part by the presence of glycosaminoglycans, proteoglycans, and ECM proteins [ 24 ]. In our previous study [ 20 ], neutralized digested B-ECM possessed shear thinning characteristic at 4 °C, indicating the material was injectable and could be applied in minimally invasive surgery using syringes or needles. According to rheological measurement, neutralized digested B-ECM showed solid-like behavior with a storage modulus (G′) of around 110 Pa.…”

“…This may have been due to the complex biological components of the ECM materials compared to the single composition of collagen type I. In our previous study [ 20 ], the composition of B-ECM was studied using the LC-MS technique. Apart from different types of collagens, B-ECM also comprises glycoprotein and proteoglycans/GAG, fibrillin, heparan sulfate, laminin, fibulin, albumin, myosin and actin, etc.…”

“…This ability may be due to the synergic effect of complexed ECM components towards macrophages. The major component of B-ECM is collagen, accounting for up to 50% of dried tissue [ 20 ]. Collagens I–III and XVII possess high-affinity ligands for LAIR-1 receptors on immune cells.…”

“…Upon binding to the collagen, the degranulation of peripheral basophils is deterred, and thus suppresses immune cell activity. Apart from collagen, GAGs were also retained in B-ECM after decellularization [ 20 ]. Negatively charged GAG chains possess the ability to bind to positively charged immunomodulatory molecules, such as chemokines, cytokines, and growth factors, and could also influence production of these molecules [ 35 ].…”