SUMMARY:
The Di Carlo group at UCLA has invented a microparticle that enables analysis of adherent cells via flow cytometry with high throughput.
BACKGROUND:
Traditional flow cytometry is a fluorescence-based technique used to characterize cells on a molecular level usually suspended in a fluid. However, many cells are inherently attached to matrix in vivo and cannot be measured easily via flow cytometry in a more physiologically-relevant state. While there are methods to analyze adherent cells via micromolded magnetic rafts, their throughput and ease of use leaves much to be desired. A high-throughput technique that allows for molecular characterization of adherent cells, which encompasses almost all cells except immune cells, would give great insight into a number of biological questions, and would be of great value to both scientific research and medicine.
INNOVATION:
The Di Carlo group at UCLA has developed a microparticle that enables the molecular analysis of a large number of cells in the adherent state. This novel particle, which acts as a ‘cell carrier’, is loaded with single cells and run through a flow cytometry instrument. As the particles are passed through the flow cytometer, the attached cells can be analyzed using scatter and fluorescence or using an imaging cytometer for brightfield- and fluorescence-based imaging. Various cell parameters, including protein localization and cytoskeletal organization, can be measured and quantified. The microparticles can have various loading areas for cells, to protect them from shear stress, broadening the study of cells using flow cytometry. The use of this microparticle in cellular analysis can provide rich data that is unattainable with traditional flow cytometry. In addition to the microparticle itself, the inventors have developed an innovative stop-flow lithography technique, which they call optical Transient Liquid Molding, that allows for the fabrication of the hydrogel cell carriers.
POTENTIAL APPLICATIONS:
- High-throughput cellular analysis when cells are in an adherent state
- Measurable parameters include:
- Cell morphology
- Protein localization
- Cytoskeleton and structural characterization
- Cell force measurements
ADVANTAGES:
- Adherent state analysis (current methods only allow for high-throughput suspension state analysis)
- Analysis of a wide spectrum of cell or microtissue sizes
- High-throughput
- May be compatible with existing flow cytometry models
DEVELOPMENT TO DATE:
The Di Carlo group has published the fabrication method in a peer reviewed journal.
RELATED PAPERS:
Wu, C. Y.; Owsley, K.; Di Carlo, D. Rapid Software-Based Design and Optical Transient Liquid Molding of Microparticles. Adv. Mater. 2015, 27 (48), 7970–7978. https://doi.org/10.1002/adma.201503308.