Watch Heart Tissue Twitch on a Chip When Drugged

This is your heart on drugs. On a chip. Any questions?

2 min read
Watch Heart Tissue Twitch on a Chip When Drugged
Photo: Anurag Mathur/Healy Lab

Who said machines don't have heart? Bioengineers have embedded pulsating human heart cells in a small microfluidic chip to model the effects of drugs on real human hearts.

Animal models are routinely used in the earliest stages of clinical trials, but they often fail to predict human reactions to new drugs because of fundamental differences in biology between species. For instance, the proteins through which ions flow in and out of heart cells can vary in both number and type between humans and other animals.

Instead, researchers at the University of California, Berkeley, hope that human heart cells grown on a chip could help replace animal testing. These cells are derived from human induced pluripotent stem cells, which are adult cells chemically modified to become many different kinds of tissue. Microfluidic channels around the cells simulate blood vessels, supplying the cells with nutrients and drugs.

The heart cells began beating on their own at a normal rate of 55 to 80 beats per minute within 24 hours of getting loaded into the device. The bioengineers tested their gadget with four well-known heart drugs, and the cells reacted as predicted — for instance, after a half-hour’s exposure to isoproterenol, a drug used to treat bradycardia (slow heart rate), the cells on the device increased their activity to 124 beats per minute.

One aim for this organ-on-a-chip is to one day help screen potential new heart drugs and see how real human hearts might respond. The heart cells in this device remained alive and functional for several weeks, during which time they could be used to test a variety of drugs, the researchers said in a press release.

The bioengineers noted their heart-on-a-chip could be modified to model human genetic diseases, or it could test how an individual might respond to a drug. One day, if it was combined with similar devices—say, a liver-on-a-chip —the combined system could study the impact of drugs on multiple interacting organs.

The scientists detailed their findings online 9 March in the journal Scientific Reports.

The Conversation (0)

This CAD Program Can Design New Organisms

Genetic engineers have a powerful new tool to write and edit DNA code

11 min read
A photo showing machinery in a lab

Foundries such as the Edinburgh Genome Foundry assemble fragments of synthetic DNA and send them to labs for testing in cells.

Edinburgh Genome Foundry, University of Edinburgh

In the next decade, medical science may finally advance cures for some of the most complex diseases that plague humanity. Many diseases are caused by mutations in the human genome, which can either be inherited from our parents (such as in cystic fibrosis), or acquired during life, such as most types of cancer. For some of these conditions, medical researchers have identified the exact mutations that lead to disease; but in many more, they're still seeking answers. And without understanding the cause of a problem, it's pretty tough to find a cure.

We believe that a key enabling technology in this quest is a computer-aided design (CAD) program for genome editing, which our organization is launching this week at the Genome Project-write (GP-write) conference.

With this CAD program, medical researchers will be able to quickly design hundreds of different genomes with any combination of mutations and send the genetic code to a company that manufactures strings of DNA. Those fragments of synthesized DNA can then be sent to a foundry for assembly, and finally to a lab where the designed genomes can be tested in cells. Based on how the cells grow, researchers can use the CAD program to iterate with a new batch of redesigned genomes, sharing data for collaborative efforts. Enabling fast redesign of thousands of variants can only be achieved through automation; at that scale, researchers just might identify the combinations of mutations that are causing genetic diseases. This is the first critical R&D step toward finding cures.

Keep Reading ↓ Show less