World Precision Instruments Launches Cell Tester - Unique Cell Biology Tool To Sense Stress And Stretch In Individual Cells

Enhancing fundamental research to understand heart muscle and blood pressure regulation

World Precision Instruments Inc recently announced the launch of the new Cell Tester, a novel cell biology research tool, set to revolutionize the emerging field of ‘mechano transduction' by allowing researchers to study the influence of mechanical force, stress or strain on cells and how these cells react to stimuli. The resulting data will help answer fundamental questions such as how do individual muscle cells sense stress and stretch? And how does this contribute to the heart's ability to adjust pumping capacity as a function of the fluid filling state?

Many cells in the human body are constantly under the influence of mechanical stresses. These include skeletal muscle cells, heart cells, so called smooth muscle cells in the wall of blood vessels and hollow organs such as the bladder and gastrointestinal tract as well as sensory neurons. Mechanical stretching activates mechano transduction signalling pathways in cells that have broad implications for cell health and disease. For example, mechanical pressures in heart and smooth muscle cells are exacerbated in patients with diseases such as high blood pressure. Insights into how these cells respond to additional stresses could give researchers valuable insight into disease progression and potentially shed light on how intervention therapies impact on these responses. The ability to do this on single cells opens up the possibility to use live human cells as an alternative to animal models of a disease within the research arena.

Working at a rate of over 1000 measurements per second, the Cell Tester employs state-of-the-art optics, nano positioning and force sensor technology to deliver sensitive, robust and reproducible force measurements. This facilitates the quantification of the very small forces that individual cells can generate – in the order of tens to hundreds of nano grams. At the same time, the instrument uses miniature piezo crystal-based motors to push or pull cells and so changes their length or imposes stress. The Cell Tester is being showcased to this year's American Heart Association Scientific Sessions 2011 in Orlando, FL, USA.

"In combination with a laser-scanning confocal microscope, we have been able to follow the fate of calcium release inside heart cells," remarked Professor W. J. Lederer, Center of Biomedical Engineering and Technology, University of Maryland School of Medicine. "Being able to gain insight into the relationship between mechanical stress and aberrant calcium release, thought to cause possible lethal arrhythmias, will help support the discovery of new targets for the treatment of heart disease."

For most cell types, fine alignment is achieved using a rotating stage and remote-controlled micro tweezers that approach and grab on to the individual cell. However for a very small subset of cells that produce high forces in relation to their size e.g. heart muscle cells this "grabbing" technique is not suitable, instead these cells are held in place by a unique proprietary polymerizing mixtures of very sticky natural biological compounds that cells use to adhere to one another combined with glass rods held by the micro grabbers. One such "glue" is Myotak, specially designed to securely hold muscle cells and allow measurement without crushing of the cell.

"We like to think of this as nanotechnology meeting cell biology", commented Harm J Knot, CSO at World Precision Instruments Inc. "We are delighted to be able to offer a novel tool that will help researchers answer such questions as how do white blood cells deform and squeeze out of the blood stream to fight infections? Why do cancer cells not sense the proximity of other cells and how do they dislodge and reseed in other parts of the body? And how do our special nerve cells sense a full bladder?"

About WPI
World Precision Instruments, Inc. (WPI) is a leading global provider of powerful, cutting-edge laboratory solutions for the life sciences. Headquartered in Sarasota, Florida and with several offices around the world, WPI is a renowned manufacturer of innovative physiological research instruments aimed at University and preclinical pharmaceutical research with a focus on smooth, striated, and cardiac muscle. www.wpiinc.com

About the Cell Tester
The Cell Tester is the product of three years of design and field testing. It represents a blending of state-of-the-art technologies, including electronics, mechanics and optics. The end result is a revolutionary new research tool for cellular investigation. The Cell Tester is for Research Only, it is not a registered Medical Device.

The Cell Tester is designed to sit on top of the stage of a standard inverted research microscope. The optical path of the microscope is left intact for simultaneous fluorescence or confocal imaging.

Nanomotor
The heart of the system is a tuned and paired combination of a linear actuator offering nanometre (nm) precision and a force transducer with nano Newton (nN) sensitivity. Each element (actuator and sensor) is equipped with a remote controlled micro grabber that allows tissues to be held firmly. In addition a non-cytotoxic adhesive (MyoTak) facilitates the bonding of tissue to the measuring device where needed.

Force Transducer
KG-series force transducers measure a large range of detectable forces. The transducer with the highest sensitivity (20nN) is sufficient to measure the force of a single heart cell. Because all transducers are extraordinarily rugged, withstanding even overload forces, they come with a lifetime warranty on the optical transducer heads.

Rotating Cuvette
The complete system utilizes a unique rotating bath to dramatically improve experimental throughput. The rotating bath is designed to orient cells in the XY plane so that no physical manipulation of the position of the cell itself is required prior to capture by the grabbing devices attached to the force sensor and linear actuator.

Electronics
WPI's Signal Conditioning Amplifier System is a customizable electronic platform. It consists of an 8-channel, rack-mountable frame with an ultra-quiet, shielded power supply. For the Cell Tester, it includes the Nanomotor controller, the SI-BAM21LCB amplifier and the SI-AOSU anti-oscillation unit. The SI-BAM21-LCB KG Optical Force Transducer Amplifier powers the force transducer and outputs an analogue voltage proportional to the force applied to the force transducer. The force feedback signal can be multiplied by a factor of 1, 2, 5 or 10 to provide better resolution for a minimal change in applied force. The anti-oscillation option eliminates the native resonance frequency of the transducer and mounting support for unparalleled low noise recording and fidelity.

Data Acquisition
The data from the Cell Tester can be recorded by any generic data acquisition system.

SOURCE: World Precision Instruments, Inc. (WPI)