Assaying Fibroblast Migration on Covalent Peptide Gradient Surfaces

Featuring:
Dr. Matt Kipper
National Institute of Standards and Technology

Location: Engineering Tower, Room 331

Abstract:
The migration of cells that are involved in the early (inflammation) stage of wound healing, such as neutrophils, macrophages, and T lymphocytes has been extensively studied for several decades. However, the migration of slower migrating cells, such as fibroblasts and endothelial cells, which are involved in the later stages of wound healing (proliferation and remodeling), is more difficult to study. Common techniques such as Boyden chamber assays, in which the cells are allowed to migrate across a membrane or filter may be good models for processes such as metastasis or extravasation, but may not be relevant models for connective tissue cells migrating across a wound. Recent research in fibroblast migration is continuing to reveal details of the cellular mechanisms of migration as well as useful models of the dynamics of migrating cell populations. This presents us with two interesting opportunities or challenges:

1. Design experiments and models for cell migration that can bridge the gap between processes occurring at the cellular or sub-cellular level and the cell population level. This is a scientific challenge.

2. Apply this improved understanding of cell migration to the rational design of materials and devices that promote   cell migration for practical applications in wound healing and tissue engineering. This is an engineering challenge.

These two challenges can be pursued simultaneously by designing our cell migration experiments around a platform or platforms that are readily adaptable to practical wound healing or tissue engineering applications. This strategy will significantly reduce the effort required to translate our new scientific knowledge into a new technology.

Therefore, the goal of this work is to develop techniques for creating covalently bound peptide gradients that can serve the following three purposes: 

1. Quantify the biological activity of different haptotactic peptides. 
2. Study the cellular responses to materials activated with peptide gradients. 
3. Promote cell migration in a clinically relevant system, such as wound healing and tissue engineering applications.

The success of this project means that the biological activity of peptides and the cell biomechanics are studied on the same platform that will be used for a practical application of an engineered material. During this talk, I will discuss a simple technique for fabricating peptide gradients on surface and gels, which is also readily adaptable to three-dimensional porous tissue engineering constructs. I wil show some results of experiments used to study fibroblast migration on laminin peptide gradients. And, I will discuss mathematical models of fibroblast migration.

About the Speaker:
Dr. Kipper received his Ph.D. from Iowa State University in 2004.  He is currently working as a postdoctoral researcher at the National Institute of Standards and Technology.  His research focuses on fabrication and characterization of novel biomaterials and surface chemistries for tissue engineering scaffolds.