The Forces That Bind
Engineer Andrés García:
Studying the Mechanics of Cell Adhesion
Andrés García Sizes Up Sticky Cells
Engineer García wants to create biomaterials to heal broken bones.
Adhesion enables cells to
Change shape
Move around the body
Repair a wound
Question:
What happens when human cells become too sticky?
Answer: Cells cannot move
How Cells Move
Cells walk along body surfaces via tiny "feet," called focal adhesions, which connect with the extracellular matrix.
To move (extend, attach, release), what must cells exert?
Forces Are With You
Types of force:
Applied―one object exerts energy on another object
Gravitational―massive celestial bodies pull on objects
Frictional―an object slides across a surface
Give an example of applied force.
Give an example of frictional force.
What non-planetary objects might this type of force affect?
García's "One Size Fits All" Solution
García Gains Momentum
How Tightly Do Cells Stick to a Surface?
Inside the cell spinner
Plate containing cells sits on a disk holder
Disk holder spins inside a chamber filled with liquid
Spinning disk generates a 3-dimensional flow pattern that applies precise pressure detachment forces to the cells
Adhesion strength is calculated by counting cells remaining adhered after spinning stops.
Answering research question #1
What Can Change Adhesion Force?
Cellular stickiness depends on
How many "feet" a cell has in one spot
Whether cells have certain proteins
Answering research question #2
Question:
Do more "feet" mean stronger or weaker adhesion?
Why?
Interdisciplinary Discovery
García's discoveries are the result of mixing concepts from two disciplines: cell biology and engineering.
Biologists study the complexities of living systems
Engineers take systems apart to measure them
Research Applications
In what ways might the knowledge that García has gained about focal adhesion mechanics be applied in human medicine?