SituationThe cell biology and physiology department of the Washington University in St. Louis has been among the top programs in the country for more than a century. These days, the department works at the forefront of genetic research, determining the role of genes and gene products in human health and disease. The workings of the cell remain at the very heart of these investigations.
Paul H. Schlesinger, M.D., Ph.D. is an associate professor within this division, with a research focus on the intracellular transport of ions, including protons, and their influence on the physiology of cells. He heads a laboratory that examines the mechanisms behind intracellular channels, along with the pore formation, activation, and in-membrane dynamics of BCl-2 proteins. The BCI-2 family of proteins has been identified as a critical instigator of cell death, a major factor in more than 500 diseases including cancer and heart disease—both leading causes of death in the United States.
While the BCI-2 family of proteins had been identified as an important area for research, studying their behavior and interactions within the cell, and with other proteins, was challenging and time-consuming. Many traditional techniques called for protein labeling, which involves a number of preparation steps and significant sample interference. Dr. Schlesinger had been implementing an alternative option, surface plasmon resonance (SPR), but his early system still restricted his laboratory’s work. Experiments had to be run sequentially with scientists manually operating the runs.
Dr. Schlesinger determined that his lab needed an SPR system upgrade to streamline protein detection and characterization. Given the resource constraints of academia, the SPR system chosen had to be cost-effective and sufficiently flexible, to cover a range of experiments. High-quality binding data and advanced sensitivity were also a priority. To achieve all of this, the SPR system would need to include:
- Rigorous kinetics analysis (association/on and dissociation/off rates)
- Affinity measurements ranging from extremely weak (1 mM) to extremely strong (1 pM) interactions
- Precise determination of thermodynamic parameters (ΔH, ΔS)
- Accurate concentration analysis
- Increased uptime, throughput and flexibility
OpportunityDr. Schlesinger’s familiarity and research called for the use of a dual channel SPR instrument. This instrument would be widely used to study lipid membranes on a chip and the interaction of proteins with those membranes. Specifically, his group wanted to learn how to control and regulate programmed cell death in situations where it influences disease.
Scientists within the department also studied how cholesterol is extracted from protein membranes and how it moves throughout the cell. The aim was to gain a better understanding of the cholesterol reflux pathway; the way cells expel cholesterol into circulation, and the biophysics and subsequent interactions after the protein is activated and binds to the surface of the membranes. Another consideration for purchasing a new SPR instrument was the ability to study interactions of up to 27 other proteins. The department needed an automated sample loading system that could run samples overnight – something the laboratory was unable to do previously.
SolutionDr. Schlesinger researched several SPR instruments and ultimately selected the Reichert SR7500DC Dual Channel SPR System. His lab switched from a competitor’s system due to the greater performance capabilities in a range of key criteria:
- Automation allowed the department to perform studies approximately 20 hours a day with greater reliability
- Cost-effective purchase price and running expense
- Robust data
- Ease-of-use, for novice and experienced scientists
- Attentive and helpful customer service staff
- Greater access to the internal system of the device
- Users can easily replace their own tubing, eliminating an otherwise costly service
- The instrument offered greater flexibility and could be manipulated as needed to suit the experimental conditions required.
SR7500DC Dual Channel SPR System
Pushing the limits of detection and sensitivity in protein interaction analysis
The SR7500DC Dual Channel SPR System supports the diverse interests of academia and industry with one of the most sensitive and flexible SPR platforms in today’s marketplace. This reliable label-free system is used to characterize a broad range of molecular interactions that are important in numerous scientific disciplines. These interactions include those occurring with and between the major classes of biological macromolecules along with those involving small molecules and drugs. Quantitative information on such interactions is critical to research efforts in pharmaceuticals, drug discovery, antibody screening, protein structure/function, gene regulation and systems biology.
Performance ResultsReichert SR7500DC vs. the competition:
- Improved sensitivity: 7x greater sensitivity for higher quality, more accurate results
- Increased efficiency: Completes 30 cycles per day for 10x more experiment runs
- Cost-effective: Purchase price is just one-third that of leading competitor’s SPR system; chips and additional supplies were 10 percent the cost
- Superior maintenance: Annual maintenance cost savings of more $5,500
- Automated and reliable: Reichert SPR increased uptime by more than 80 percent
- Increased flexibility: Reichert’s intuitive, powerful software provided maximum flexibility compared to the legacy SPR system
Next StepsDue to the positive experience with the Reichert SR7500DC Dual Channel SPR System, Dr. Schlesinger is actively seeking out the Reichert4SPR for his next instrument upgrade.
"The Reichert SR7500DC is a complete solution for research laboratories involved in the study of molecular interactions. I was impressed by Reichert's intuitive and easy to use system that allowed a range of types of binding interactions to be explored. Reichert's versatility, flexibility and strong support, made it easy to generate top-quality data. What used to take us weeks to analyze is now done in a matter of days. I would highly recommend Reichert when choosing an SPR instrument."
Paul H. Schlesinger, M.D., Ph.D.
Associate Professor and Principal Investigator
Washington University in St. Louis
"Dr. Schlesinger was searching for an automated robust and reliable SPR system with relatively low running costs while providing high quality data for interactions of interest. Reichert demonstrated not only that the SR7500DC system offers exceptional value but more importantly, was able to acquire high quality kinetic data for Dr. Schlesinger's demanding interaction applications showing that the Reichert system was the best solution to meet his research needs and budget. We are honored to have Dr. Schlesinger as a customer knowing that kinetic and affinity data acquired on the Reichert SR7500DC is helping to carry out the outstanding research being done at Washington University."
Phillip Page, Ph.D.
Field Application Scientist
Reichert Life Sciences
REICHERT SPR SYSTEMS
- Better sensitivity
- Broader range of experiments
- Higher throughput and uptime
- Lower capital and running costs