Opportunity
The study of cell-cell interactions is crucial for understanding biological processes and developing medical applications such as drug screening. Traditional cell coculture methods involve randomly mixing different cell types on a Petri dish, relying on spontaneous cell rearrangement due to differences in intercellular adhesiveness. However, these methods offer limited control over the final cell pattern, making it difficult to study specific interactions systematically. Existing engineering approaches for organized patterning coculture often require complex device fabrication, multi-step cell loading and washing, or rely on non-biocompatible buffers and external fields (e.g., electric fields). These limitations hinder their practicality and compatibility with microfluidic systems. There is a clear need for a simple, flexible, and biocompatible platform that enables precise patterning and coculturing of multiple cell types in a controlled manner.
Technology
The patent introduces a microfluidic apparatus and method for patterning and coculturing biological cells using a combination of gravitational sedimentation and laminar flow. The apparatus includes a fluidic structure with multiple inlets and an outlet, allowing simultaneous loading of different cell types. A flow-controlling device (e.g., a negative pressure pump) drives the cells through the fluidic structure, where they are arranged in a predetermined laminar flow pattern. Key innovations include:
1. Gravitational Sedimentation: Cells sediment to the bottom of tubular structures connected to the inlets, forming focused cell streams. This process is independent of cell size, enabling the patterning of diverse cell types.
2. Adjustable Cell Patterning: By altering the steering angle of the tubular structures, the position of cell strips in the fluidic channel can be flexibly adjusted without redesigning the chip.
3. Integration with Gradient Generators: The apparatus can be coupled with tree-shaped microfluidic gradient generators to create concentration gradients of cell medium solutions, facilitating studies under varying biochemical conditions.
4. One-Step Operation: Multiple cell types can be loaded and patterned simultaneously, simplifying the process compared to multi-step traditional methods.
Advantages
- Simplicity: Eliminates the need for complex sheath flow systems or prepatterned surfaces.
- Flexibility: Cell patterns can be adjusted in real time by changing tubing steering angles.
- Biocompatibility: No external fields or non-biocompatible buffers are required.
- High Throughput: Enables simultaneous patterning and coculturing of multiple cell types.
- Scalability: The number of inlets can be scaled to accommodate more cell types.
Applications
- Drug Screening: Study cell responses to different drug concentrations under controlled coculture conditions.
- Cell-Cell Interaction Research: Investigate communication between cancer cells and stromal cells.
- Tissue Engineering: Mimic natural tissue morphologies for organ-on-a-chip applications.
- High-Throughput Assays: Parallel testing of cellular behaviors under gradient conditions.
