Tenfold boost in ability to pinpoint proteins
20 Mar 2013
A novel colour-coding method has enabled researchers to illuminate 100 biomarkers.
This is a ten-time increase from the current research standard and is hoped to help researchers analyse individual cells from cultures or tissue biopsies.
“Discovering this process is an unprecedented breakthrough for the field,” said corresponding author Xiaohu Gao, a UW associate professor of bioengineering at Washington University.
“This technology opens up exciting opportunities for single-cell analysis and clinical diagnosis.”
The research builds on current methods that use a smaller array of colours to point out a cell’s biomarkers - characteristics that indicate a special, and potentially abnormal or diseased cell.
Ideally, scientists would be able to test for a large number of biomarkers, then rely on the patterns that emerge from those tests to understand a cell’s properties.
This technology opens up exciting opportunities for single-cell analysis and clinical diagnosis
The research team has created a cycle process that allows scientists to test for up to 100 biomarkers in a single cell. Before, researchers could only test for 10 at a time.
The analysis uses quantum dots, which are fluorescent balls of semiconductor material. These quantum dots are between 2 and 6 nanometers in diameter, and they vary on the colour they emit depending on their size.
Though many quantum dot papers have tried to expand the number of biomarkers tested for in a single cell, this method essentially reuses the same tissue sample, testing for biomarkers in groups of 10 in each round.
“When you treat with promising drugs, there are still a few cells that usually don’t respond to treatment,” said Gao. “They look the same, but you don’t have a tool to look at their protein building blocks. This will really help us develop new drugs and treatment approaches.”
The process is relatively low-cost and simple, and Gao hopes the procedure can be automated. He envisions a chamber to hold the tissue sample, and wire-thin pumps to inject and vacuum out fluid between cycles.
A microscope underneath the chamber would take photos during each stage. All of the images would be quantified on a computer, where scientists and physicians could look at the intensity and prevalence of colors.
Gao hopes to collaborate with companies and other researchers to move toward an automated process and clinical use.
“The technology is ready,” Gao said. “Now that it’s developed, we’re ready for clinical impacts, particularly in the fields of systems biology, oncology and pathology.”
