A device for simultaneous live cell imaging during uni-axial mechanical strain or compression

• Published in: Journal of applied physiology (1985) 2009-08, Vol.107 (2), p.613-620
• Main Authors: Gerstmair, Axel, Fois, Giorgio, Innerbichler, Siegfried, Dietl, Paul, Felder, Edward
• Format: Article
• Language: English
• Subjects: Algorithms; Animals; Biological and medical sciences; Cell Adhesion; Cell Culture Techniques - instrumentation; Cell growth; Cell Shape; Cells, Cultured; Elasticity; Equipment Design; Fundamental and applied biological sciences. Psychology; Image Processing, Computer-Assisted; Male; Materials Testing; Mechanotransduction, Cellular; Medical imaging; Membranes; Membranes, Artificial; Microscopy, Fluorescence; Physiology; Pulmonary Alveoli - cytology; Pulmonary Alveoli - physiology; Rats; Rats, Sprague-Dawley; Signal transduction; Stress, Mechanical; Time Factors
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00012.2009

1 Institute for General Physiology, University of Ulm, Ulm, Germany; and 2 Innerbichler GmbH, Breitenbach am Inn, Austria Submitted 9 January 2009 ; accepted in final form 28 May 2009 Mechanical stimuli control multiple cellular processes such as secretion, growth, and differentiation. A widely used method to investigate cell strain ex vivo is stretching an elastic membrane to which cells adhere. However, simultaneous imaging of dynamic signals from single living cells grown on elastic substrates during uni-axial changes of cell length is usually hampered by the movement of the sample along the strain axis out of the narrow optical field of view. We used a thin, prestrained, elastic chamber as growth substrate for the cells and deformed the chamber with a computer-controlled stretch device. An algorithm that compensates the lateral displacement during stretch kept any selected point of the whole chamber at a constant position on the microscope during strain or relaxation (compression). Adherent cells or other materials that adhere to the bottom of the chamber at any given position could be imaged during controlled positive (stretch) or negative (compression) changes of cell length. The system was tested on living alveolar type II cells, in which mechanical effects on secretion have been intensively investigated in the past. mechanotransduction; motion compensation; elastic membrane; alveolar Address for reprint requests and other correspondence: E. Felder, Institute for General Physiology/M-25, Univ. of Ulm, Albert Einstein Allee 11, 89081 Ulm, Germany (e-mail: edward.felder{at}uni-ulm.de )