Hybrid Cartilage Construct with Inflatable Bio-Polymer Balloons
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for repairing articular cartilage and intervertebral discs are inadequate due to limited nutrient supply, invasive procedures for cell harvesting, and complications from surgical treatments like discectomy and spinal fusion, which often lead to further degeneration and complications.
Innovation Solution
A hybrid construct combining an inert, biodegradable scaffold with a living core of chondrocyte-like cells derived from Human Dermal Fibroblasts, which acts as both a nutrient delivery system and a bioreactor, providing mechanical stress for differentiation and growth within the disc, allowing for minimally invasive implantation and self-maintenance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional tissue engineering methods are used with biodegradable scaffolds, then cartilage regeneration is possible, but nutrient supply to cells is limited and cell growth is insufficient
Solution Approach 1:
The patent introduces a dual-membrane encapsulation system where the first membrane (semipermeable) and second membrane (permeable) act as intermediaries to control and enhance nutrient transport. The second membrane specifically serves as a mediator that allows free passage of nutrients and waste products, solving the limitation of nutrient supply while maintaining the structural integrity needed for cartilage regeneration
Solution Approach 2:
The patent employs porous biodegradable scaffolds with controlled pore sizes and distributions to enhance nutrient diffusion throughout the construct. The porous structure of both the scaffold and the second membrane creates interconnected pathways that facilitate efficient nutrient supply to cells throughout the entire cartilage construct, addressing the nutrient limitation problem
2Reliability
If autologous chondrocytes are harvested for transplantation, then patient-specific cartilage repair is achieved, but invasive surgical procedures are required
Solution Approach 1:
The patent performs preliminary action by harvesting and expanding chondrocytes ex vivo before transplantation. Cells are collected through a initial biopsy, then cultured and expanded in vitro to generate sufficient cell numbers for the repair procedure. This preliminary cell preparation eliminates the need for invasive intraoperative cell harvesting and allows for optimized cell expansion under controlled conditions
Solution Approach 2:
The patent utilizes the patient's own chondrocytes that are harvested once and then self-multiply through ex vivo culture expansion. The cells serve themselves by proliferating in culture media to generate the required cell population, eliminating the need for repeated invasive harvesting procedures and providing sufficient cells for the transplantation procedure
3Reliability
If surgical treatments like discectomy and spinal fusion are performed, then disc pathology is addressed, but further degeneration and complications occur
Solution Approach 1:
The patent converts the harmful effect of disc degeneration into a beneficial opportunity for regeneration. Instead of removing degenerated tissue through discectomy or fusing vertebrae, the invention uses the degenerated disc space as the target site for injecting the encapsulated cartilage construct. The degenerated area becomes the precise location where new healthy cartilage is needed, transforming the pathological site into a regenerative opportunity
Solution Approach 2:
The patent extracts only the necessary components for repair - the degenerated disc tissue is removed minimally to create space for the construct, while preserving the surrounding healthy structures. The encapsulated cartilage construct is then injected into this created space, providing repair without the extensive tissue removal and structural alteration required by traditional discectomy or fusion procedures
4Quantity of substance
If cells are cultured in vitro for tissue engineering, then cell proliferation is achieved, but differentiation into chondrocyte-like cells is insufficient
Solution Approach 1:
The patent employs parameter changes by subjecting cultured cells to mechanical compression forces during the culture process. This mechanical stimulation changes the physical parameters of the culture environment, inducing cells to differentiate into chondrocyte-like phenotypes while maintaining high cell numbers. The compression parameters (force magnitude, frequency, duration) are optimized to achieve both proliferation and differentiation simultaneously
Solution Approach 2:
The patent applies periodic mechanical compression to the cell cultures rather than continuous or static conditions. This periodic mechanical stimulation, applied at specific frequencies and durations, triggers differentiation signals while allowing cell proliferation between stimulation cycles. The rhythmic nature of the mechanical action mimics physiological loading conditions that promote chondrogenic differentiation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables effective regeneration of cartilage by providing necessary nutrients and mechanical stimuli, reducing the need for invasive cell harvesting and minimizing surgical complications, promoting self-maintenance and remodeling of the disc tissue.
Implementation Method 1
The first membrane is semi-permeable and allows diffusion of nutrients and oxygen to the cell-matrix construct
Implementation Method 2
transmitting a physiologic loading regimen, which comprises mechanical stress and/or hydrostatic pressure
Implementation Method 3
transmitting a physiologic loading regimen, which comprises mechanical stress and/or hydrostatic pressure
Data Source
AI summary
Methods and compositions for the biological repair of cartilage using a hybrid construct combining both an inert structure and living core are described. The inert structure is intended to act not only as a delivery system to feed and grow a living core component, but also as an inducer of cell differentiation. The inert structure comprises concentric internal and external and inflatable/expandable balloon-like bio-polymers. The living core comprises the cell-matrix construct comprised of HDFs, for example, seeded in a scaffold. The method comprises surgically removing a damaged cartilage from a patient and inserting the hybrid construct into the cavity generated after the foregoing surgical intervention. The balloons of the inert structure are successively inflated within the target area, such as a joint, for example. Also disclosed herein are methods for growing and differentiating human fibroblasts into chondrocyte-like cells via mechanical strain.