Generation of Gellan Gum-Based Adipose-Like Microtissues

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Stem Cell Biology

Background:

• Adipose tissue plays crucial roles in physiology, necessitating biomaterials for tissue reconstruction and in vitro models.
• Gellan gum (GG) offers natural properties suitable for developing adipose-like analogues.

Purpose of the Study:

• To explore gellan gum's potential for creating injectable, stable adipose-like microtissues.
• To evaluate the impact of GG hydrogel mechanical properties on human adipose-derived stem cell (hASC) adipogenic differentiation.
• To assess the utility of these constructs for soft tissue reconstruction and drug screening.

Main Methods:

• Gellan gum hydrogel particles were fabricated with varying polymer concentrations (0.5%, 0.75%, 1.25%).
• The mechanical properties (Young's moduli) of the hydrogels were characterized.
• hASCs were cultured within the hydrogels and induced towards adipogenesis, with differentiation assessed via marker gene expression (PPARγ, FABP4), lipid accumulation, and construct stability.
• Sensitivity to TNFα and ROCK inhibitor was tested to evaluate drug screening capabilities.

Main Results:

• No significant differences in hASC adipogenic differentiation were observed across Young's moduli ranging from 2.7 to 12.9 kPa.
• The developed GG constructs demonstrated long-term stability (up to six weeks).
• The microtissues responded to TNFα (inhibiting differentiation) and ROCK inhibitor (inducing differentiation), validating their use as drug screening models.

Conclusions:

• Gellan gum is a viable material for fabricating injectable, stable adipose-like microtissues.
• The mechanical properties within the tested range did not significantly impede adipogenic differentiation.
• These engineered microtissues show promise for both soft tissue reconstruction and as functional in vitro models for pharmaceutical testing.