Immunological characteristics of human umbilical cord mesenchymal stem cells after hepatogenic differentiation

Stem Cell-Based Strategies: The Future Direction of Bioartificial Liver Development

Acute liver failure (ALF) results from severe liver damage or end-stage liver disease. It is extremely fatal and causes serious health and economic burdens worldwide. Once ALF occurs, liver transplantation (LT) is the only definitive and recommended treatment; however, LT is limited by the scarcity of liver grafts. Consequently, the clinical use of bioartificial liver (BAL) has been proposed as a treatment strategy for ALF. Human primary hepatocytes are an ideal cell source for these methods. However, their high demand and superior viability prevent their widespread use. Hence, finding alternatives that meet the seed cell quality and quantity requirements is imperative. Stem cells with self-renewing, immunogenic, and differentiative capacities are potential cell sources. MSCs and its secretomes encompass a spectrum of beneficial properties, such as anti-inflammatory, immunomodulatory, anti-ROS (reactive oxygen species), anti-apoptotic, pro-metabolomic, anti-fibrogenesis, and pro-regenerative attributes. This review focused on the recent status and future directions of stem cell-based strategies in BAL for ALF. Additionally, we discussed the opportunities and challenges associated with promoting such strategies for clinical applications.

Hydrogel composed of type II collagen, chondroitin sulfate and hyaluronic acid for cartilage tissue engineering

BACKGROUND

Cartilage tissue engineering is a promising way to repair cartilage defects. Different materials have been applied in the preparation of cartilage hydrogels, but all with various disadvantages.

OBJECTIVE

The aim of this study was to prepare cartilage hydrogel using type II collagen, chondroitin sulfate and hyaluronic acid, to explore their gelation effect and compressive strength, and to analyze the feasibility of their application in cartilage tissue engineering.

METHODS

Type II collagen (Col II), hyaluronic acid (HA) and chondroitin sulfate (CS) were mixed in a certain proportion to prepare gel scaffolds; changes in chemical groups were detected by Fourier transform infrared. After the hydrogel was prepared, its compressive strength was measured. Umbilical cord stem cells were co-cultured with hydrogel scaffolds to observe its cytocompatibility and analyze whether stem cells had cellular activity during co-culture; histological staining was applied to observe the hydrogel loaded with stem cells.

RESULTS

Cartilage hydrogels were successfully prepared with good compressive strength, and Fourier transform infrared analysis showed that Schiff base reaction occurred during the preparation process and tight chemical cross-linking was formed. The results of umbilical cord stem cell co-culture showed that the hydrogel had good cytocompatibility and the stem cells had good activity in the hydrogel.

CONCLUSIONS

Cartilage hydrogels with stable structures were successfully prepared and had good compressive strength. Hydrogel scaffold could provide a suitable living environment for umbilical cord stem cells, so that they maintain normal cell morphology and activity, and has a good application potential in cartilage tissue engineering.