Baby mice may be small, but they are also annoying. For the first seven days of their life, they have the unique ability to regenerate damaged heartbeat.
On the other hand, people are less fortunate: any heart injury we suffer could cause permanent damage. But what if we could learn to repair our hearts, just like baby mice?
A team of researchers led by UNSW Sydney has developed a microchip that will help scientists study the regenerative capacity of mouse heart cells. This microchip – which combines microengineering with biomedicine – could help pave the way for a new regenerative heart therapy study.
The study appears on the cover of today’s issue of the magazine Small.
“We have developed a simple, reliable, inexpensive and fast way to identify and differentiate these important mouse heart cells,” says lead author Dr. Hossein Tavassoli, biochemical engineer and gas cell researcher at UNSW Medicine & Health did this work as part of his doctoral dissertation.
“Our method uses a microchip that is easy to make and can be made in any laboratory in the world.”
The process for identifying and separating mouse heart cells is somewhat complicated.
First, scientists need to differentiate between the right kind of heart cells (called persistent cardiomyocytes) from other types of cells present in the heart.
Their next challenge is to keep the cells alive.
“The heart cells of newborn mice (called persistent cardiomyocytes) are highly sensitive,” says Dr. Vashe Chandrakanthan, a senior researcher at UNSW Medicine & Health and co-author of the study.
“Only about 20 percent usually survive the process of normal isolation and isolation. If we want to study these cells, we need to separate them before they lead to cell death.”
Dr Tavassoli says this new method is much more effective.
“We reduce the pressure on these cells by reducing their isolation and processing time,” he says. “Our method can clear millions of cells in less than 10 minutes.
“Almost every cell survived when we used our microfluidic chip – more than 90 percent.”
The spindle-shaped machine is a microfluidic chip – that is, a chip designed to handle lifts on a small scale. It differentiates cells according to their size, separating the cardiomyocytes from other cells. The chip costs less than $ 500 to produce, making it cheaper than other loneliness and separation methods.
This tool will make it easier for researchers to study how baby mice repair their hearts – and whether humans can use the same technique.
Heart disease is the number one killer of the world. In Australia, someone dies of heart disease every 12 minutes, and every four hours a baby is born with a heart defect. We hope our tool will help speed up heart disease research. “
Dr Hossein Tavassoli, Principal Research Author and Biomedical Engineer, Stem Cell Researcher, Medicine & Health, University of New South Wales
Identifying mouse heart cells
As soon as the heart cells were separated from other cells with the help of their chip, the researchers took the opportunity to study the physico-mechanical properties of the cells – that is, the way in which they dealing with force.
This involved asking questions such as ‘How do these individual heart cells react? ‘,’ Do the cells have special properties? and ‘What are their differences in size, shape and elasticity?’.
The findings could provide new insights for the development of products that repair cardiac arrest, such as heart packs, scaffolds and filters.
“Rapid, large-scale identification of the physico-mechanical properties of cells is a relatively new area of research,” says Dr. Tavassoli, who originally trained as an engineer before specializing in medicine.
“This is the first time that microfluidic technology has been used to study the mechanical properties of baby mouse heart cells.”
Multi-layered microchip
Dr. Chandrakanthan says that although the microchip was created for the heart cells of a child’s mouse, it could have been adapted for use in other types of cell applications.
“The principles are consistent with separating cardiomyocytes from mouse heart cells of all ages,” he says.
“We could also use this method to differentiate not only the heart cells, but all cell types from different organs.”
Dr. Tavassoli says this approach could help other areas of medical study, including cardiac biology, drug discovery and nanoengineering. He is currently conducting research at the Garvan Institute and the Lowy Cancer Research Center on how this approach would help with cancer diagnosis.
“This microchip opens up the opportunity for new research by researchers around the world,” he says.
Source:
University of New South Wales
Magazine Reference:
Tavassoli, H., et al. (2020) Unlabeled Isolation and Single Cell Biophysical Phenotyping Analysis of Primary Cardiomyocytes Using Inertial Microfluidics. Small. doi.org/10.1002/smll.202006176.