Patterned Cell Sheets via Temperature-Responsive Substrate Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing patterned cell sheets are limited by the need for complex substrate preparation, difficulty in releasing freestanding sheets, and the inability to effectively co-culture multiple cell types, especially at optimal growth conditions.
Innovation Solution
A method utilizing substrates with inducible shape transition properties and alterable surface characteristics, combined with releasing agents like EDTA, trypsin, or physical stimuli, to facilitate the release of patterned cell sheets without damaging the cells, allowing for the production of freestanding heterogeneous cell sheets with multiple cell types.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional substrates are used for cell culture, then cell growth and proliferation can proceed, but the cell sheets cannot be easily released and translocated
Solution Approach 1:
The substrate's surface characteristics are made dynamically changeable through temperature control. At culture temperature (37°C), the substrate maintains high cell adhesion; at release temperature (room temperature or lower), the substrate surface becomes hydrophilic and releases cells. This dynamic property allows the same substrate to provide both strong attachment during culture and easy release during harvesting.
Solution Approach 2:
The invention changes the temperature parameter to control substrate surface properties. By lowering the temperature from 37°C to room temperature or below, the substrate surface undergoes a hydrophobic-to-hydrophilic transition, which fundamentally alters cell adhesion strength and enables release without mechanical force or enzymatic treatment.
2Adaptability or versatility
If multiple cell types are co-cultured to create heterogeneous patterns, then complex tissue reconstruction is enabled, but the substrate preparation becomes very complicated involving multiple electron beam irradiation steps
Solution Approach 1:
The cell sheet fabrication process is segmented into separate stages: first, a continuous cell sheet is grown on the temperature-responsive substrate; second, patterned release is achieved by selectively lowering temperature in specific regions; third, different cell types can be seeded in the released patterns. This segmentation eliminates the need for complex pre-patterning of the substrate itself.
Solution Approach 2:
The temperature-responsive substrate acts as an intermediary that enables pattern transfer without requiring direct physical patterning. By using temperature fields as a mediator, the invention simplifies substrate preparation while still achieving precise spatial control over cell sheet patterns for heterogeneous co-culture.
3Reliability
If cells are tightly attached to substrate by extracellular matrix proteins for stable culture, then cell proliferation is maintained, but the release of cell sheets becomes cumbersome
Solution Approach 1:
The invention uses periodic temperature cycling: the substrate is maintained at 37°C during cell culture to ensure stable attachment and proliferation, then temporarily lowered to room temperature or below for release. This periodic temperature action allows the system to alternately provide strong adhesion and easy release without compromising cell health.
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
Enables the easy release and translocation of patterned cell sheets, maintaining cell viability, and facilitates the production of complex tissues by allowing for the co-culture of multiple cell types in specific patterns, addressing the limitations of existing methods.
Implementation Method 1
substrate comprising inducible shape transition properties
Implementation Method 2
substrate comprising alterable surface characteristics
Implementation Method 3
deposition of proteolytic enzymes onto the membranous tissue effective to biologically etch the surface
Implementation Method 4
the remaining cells are tightly attached to the substrate by means of extracellular matrix proteins, like collagen and, among others, fibrin, elastin, fibronectins, laminins, nidogen and integrins, as well as due to mere adhesive and electrostatic forces
Data Source
Figure 1a~1b
Figure 2A~2C
Figure 3
AI summary
The present invention is related to a method for the production of cell sheets comprising at least two different cell types, said method comprising the steps of providing a continuous cell sheet which is disposed on a substrate comprising shape transition properties and/or alterable surface characteristics; exposing said continuous cell sheet to a releasing agent in a patterned fashion; washing the cell sheet after expo¬ sure to the releasing agent in order to remove cells which have been affected by the releasing agent, and repopulating the gaps remaining after the cells which have been affected by the releasing agent have been removed with a second cell type.