Scientists developed three‑dimensional human heart‑like organoids that beat rhythmically and are about the size of a lentil. The organoids include chamber‑like structures and a network of arteries, veins and capillaries. Researchers make them from donated human stem cells.
The team added immune cells, including macrophages, and then caused inflammation inside the organoids. The inflammation triggered an irregular heartbeat like atrial fibrillation. When the researchers gave an anti‑inflammatory drug, the rhythm partially returned to normal. The models can help study disease and test new treatments.
Difficult words
- organoid — small laboratory-grown structures like organsorganoids
- stem cell — cells that can become different human cellsstem cells
- inflammation — body reaction causing redness and swelling
- macrophage — white blood cells that eat germs and debrismacrophages
- atrial fibrillation — an irregular fast heartbeat in the heart
- capillary — very small blood vessels in the bodycapillaries
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