生物学：人工筋肉パッチが傷ついた心臓を修復するかもしれない

A muscle patch developed using stem cells can help to repair failing hearts without adverse effects, according to a Nature paper. The favourable results are demonstrated in primate models and one human patient. Human clinical trials will further test the safety and effectiveness of this approach, but the latest findings highlight the potential of using stem cell-derived tissue patches to treat heart failure.

Heart failure remains a leading cause of death worldwide, but treatment options to reverse its course are limited. Heart transplants are associated with limited organ availability and immune suppression, and synthetic heart devices can be costly. An alternative option is implanting heart muscle cells to fix the failing heart, but retention rates are usually low and severe side effects can include arrhythmia and tumour growth.

Wolfram-Hubertus Zimmermann and colleagues engineered heart muscle patches using induced pluripotent stem cells, which are cells that can differentiate into any cell type in the body. Induced pluripotent stem cells hold promise as a cell source for cardiac repair owing to their ability to self-renew and to differentiate into cardiomyocytes, which provide sufficient cardiac tissue for grafting onto hearts. They found these patches to be effective in treating heart failure and improving heart function, including increasing heart wall thickness and contractility, when tested in Rhesus macaques over a 3–6-month period. These findings led to the approval of a clinical trial in humans, with preliminary results showing that the engineered heart muscle patches could safely remuscularize the heart of a human patient with advanced heart failure.