When conducting cardiac research, it would be ideal if experiments could be performed on actual living human hearts. Scientists have developed what may be the next-best thing, in the form of a tiny mechanical heart powered by real cardiac cells.
Created by a team at Boston University, the flat-bodied "cardiac miniaturized Precision-enabled Unidirectional Microfluidic Pump" – or miniPUMP, for short – measures just 3 sq cm (0.5 sq in). It replicates the function of a real heart's ventricle (lower chamber), pumping water through itself in the same way that an actual heart pumps blood.
The device consists of a plastic base, mounted upon which are minuscule 3D-printed acrylic valves, tubes, and the actual pump itself.
That pump incorporates a scaffold made up of a series of linked concentric acrylic spirals. These are seeded with live human cardiomyocytes (heart muscle cells). As those cells expand and contract in unison, the flexible scaffold moves with them, pumping water through the miniPUMP.
The cardiomyocytes can be obtained by starting with skin cells, blood cells, or pretty much any other type of easily-accessible cells. These are reprogrammed into stem cells, which are then prompted to differentiate into heart cells. This means that patients could have miniPUMPs made from their own cells, to see how different medications might affect their heart specifically.
"With this system, if I take cells from you, I can see how the drug would react in you, because these are your cells," said the lead scientist, postdoctoral researcher Christos Michas. "This system replicates better some of the function of the heart, but at the same time, gives us the flexibility of having different humans that it replicates."
It is hoped that the same technology could one day be used to produce other so-called "organ-on-a-chip" devices, such as lungs and kidneys. In fact, this isn't the first heart-on-a-chip we've seen – differently-designed models have been developed at Harvard University and the University of California at Berkeley, among other places.
The research is described in a paper that was recently published in the journal Science Advances.
Source: Boston University
