Physics Department

The University of Texas at Arlington

 

COLLOQUIUM

Candidate for Assistant Professor of Physics

in Nano-Bio Physics

___________________________________

 

Integrated Nano-Imaging Techniques Applied

to Live Cell Dynamics

 

Dr. Andreea Trache

 

Texas A&M University System Health Science Center

 

Thursday, February 16, 2006

4:00 p.m., Room 121 SH

 

 

Abstract

A novel hybrid imaging system that integrates Atomic Force Microscopy (AFM) with optical imaging will be presented. The main application of this instrument is the study of mechanotransduction with emphasis on integrin-extracellular matrix interactions and their role in the cell response to changes in external chemical and mechanical factors. The AFM allows monitoring of the cytoskeletal changes, binding probability, adhesion forces and micro-mechanical properties of the cells (stiffness, loading rates, bond energy and life time), while the optical imaging allows thin sectioning of the cell body only at the coverslip-cell interface permitting the study of focal adhesions using TIRF (Total Internal Reflection Fluorescence) and IRM (Internal Reflection Microscopy). Combined AFM - optical imaging experiments show that mechanical stimulation on the apical surface induces a force-generating cytoskeletal response resulting in focal contact reorganization on the basal surface that can be monitored in real time. This instrument is also equipped with a mechanically aligned dual camera acquisition system for synthesized FRET (Forster Resonance Energy Transfer). The unique opportunities offered by AFM for single-force spectroscopy integrated with the optical imaging of live cells create a powerful technology that can be used to understand the behavior of cells under defined loads, an important stimulus for many vascular cell functions including contraction and relaxation, proliferation, migration and cell attachment. These functions define physiological properties of the vasculature such as control of blood flow, capillary pressure and permeability, and play a role in pathophysiological processes like hypertension and atherosclerosis.

 

Refreshments will be served in the Physics Library at 3:30pm, 108 Science Hall