Anatomical meniscus construct with zone specific biochemical composition and structural organization.

Area of Science:

• Biomaterials Engineering
• Tissue Engineering
• Orthopedic Research

Background:

• The meniscus is crucial for knee joint function, but injuries often lead to degeneration.
• Current treatments for meniscus damage have limitations.
• Developing functional meniscus replacements remains a significant challenge.

Purpose of the Study:

• To engineer a PCL/hydrogel composite scaffold that mimics the structural, biochemical, and anatomical features of the native meniscus.
• To evaluate the mechanical properties and cellular response of the engineered construct.
• To create a functional meniscus with distinct inner and outer regions.

Main Methods:

• Fabrication of polycaprolactone (PCL) scaffolds with circumferentially aligned strands to mimic collagen organization.
• Incorporation of gelatin methacrylate (GelMA) and agarose (Ag) hydrogels loaded with human fibrochondrocytes.
• Assessment of mechanical properties (compressive and tensile modulus).
• Evaluation of cell alignment, gene expression (COL1A2, AGG, COL2A1), and protein production (COL 1, COL 2).

Main Results:

• PCL scaffolds with circumferential strands exhibited significantly enhanced mechanical properties.
• Circumferential PCL strands promoted fibrochondrocyte elongation and alignment.
• GelMA and GelMA-Ag hydrogels significantly upregulated gene expression for collagen type I, aggrecan, and collagen type II compared to PCL scaffolds.
• The engineered anatomical scaffold demonstrated a gradient of collagen type I and II expression, mimicking native meniscus zonation.
• Enhanced production of collagen type I and II proteins was observed in the hydrogel components.

Conclusions:

• A PCL/hydrogel construct was successfully engineered to replicate meniscus anatomy and biochemistry.
• The scaffold design and material composition support fibrochondrocyte alignment and extracellular matrix production.
• This biomimetic meniscus construct holds promise for future regenerative strategies in treating meniscus injuries.