Researchers at Michigan State University developed the first working human heart‑like organoids that can model atrial fibrillation. Work began in 2020 under Aitor Aguirre. The three‑dimensional organoids are roughly the size of a lentil, beat rhythmically and include chamber‑like structures plus vascular networks with arteries, veins and capillaries.
The organoids are made from donated human stem cells. Colin O’Hern, a physician‑scientist student, added immune cells such as macrophages, which help developing human hearts form correctly. The team induced inflammation in the organoids and triggered an irregular heartbeat that mimics A‑fib. They then applied an anti‑inflammatory drug and saw the rhythm partially normalize.
The findings were published in Cell Stem Cell. The results suggest that long‑lived innate immune cells in organs guide heart development and rhythm, and they may help explain some congenital heart disorders. The group is collaborating with pharmaceutical and biotech partners to screen compounds for arrhythmia and heart safety.
Difficult words
- organoid — small three-dimensional structures made from cellsorganoids
- atrial fibrillation — an irregular, rapid heartbeat conditionA‑fib
- stem cell — a cell that can develop into different cell typesstem cells
- macrophage — a white blood cell that eats germs and debrismacrophages
- inflammation — the body's reaction to injury or infection
- congenital — present from birth, often a medical condition
- vascular — related to the body's blood vessels and circulation
- arrhythmia — an abnormal heart rhythm that is irregular
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Discussion questions
- How could organoids like these change the way scientists test heart medicines?
- What are the benefits and possible limits of using donated human stem cells for this research?
- How might immune cells influence heart development in babies, based on the article?
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