Comparative characterization of hydrogels from human amniotic membrane and umbilical cord: biological and physicochemical properties.

Background: Various forms of decellularized extracellular matrix (dECM), including patches, powders, and hydrogels, have been applied to tissue engineering. Due to a broad need for alternatives to dECM, mostly derived from animal sources, human amniotic membrane (AM) and umbilical cord (UC) as disposable birthing materials can be suitable candidates. The present study developed hydrogels from AM and UC hydrogels and compared their physicochemical and biological properties.

Materials and methods: The decellularized and powdered AM and UC tissues were solubilized with pepsin to form pre-gel solutions. The developed hydrogels underwent biological and physicochemical assessments using techniques such as western blot, scanning electron microscopy, immunohistochemistry, and histopathology.

Results: UC hydrogel demonstrated a higher elastic modulus and shorter gelation time. Although the western blot results did not show significant differences in concentration of the main ECM components, specific staining showed a higher content of mucopolysaccharides in UC hydrogel as well as collagen fibers in AM hydrogel. Both hydrogels induced a fibroblast-like morphology in the cytoplasm of mesenchymal stromal cells (MSCs). Both hydrogels are suitable for 3D culture systems and support in vivo myogenic differentiation of MSCs. Finally, the hydrogels were found to be biocompatible in vivo and showed infiltration and colonization by host cells in mice.

Conclusion: This study highlights significant bio-physicochemical variations between human UC and AM hydrogels, emphasizing the need for careful consideration in their application for tissue reconstruction, in vitro culture systems, and cell-delivery techniques.