The team reproduced novel method using two stem cell lines generated decades apart by two different laboratories using different techniques.
The study published in the journal Cell Reports in March 2019, reports that priming stem cells to become heart tissues could potentially enable heart regeneration stem cell therapies. Led by senior author Professor Karl Tryggvason, Tanoto Foundation Professor in Diabetes Research at Duke-NUS’ CVMD Programme, the team comprising scientists from Singapore, the UK, Sweden, and the Netherlands investigated a heart muscle associated protein called laminin for promoting the differentiation of human embryonic stem cells into heart cell precursors. Laminins are attached to the outer parts of cell membranes and they play a role in the differentiation of precursor cells into other types of cells.
Prof Tryggvason and his team produced laminin-221 in the laboratory by stimulating the human genes that code for this protein. Laminin-221 was then used to coat a culture of pluripotent human embryonic stem cells. Furthermore, research team used laminin-521 to support growth of the stem cells and organic compounds called CHIR99021 to boost stem cell differentiation. This novel method allowed stem cells to differentiate into cardiovascular precursor cells. Although these included three main sub-populations: cardiac muscle-like cells, fibroblast-like cells, and epithelial-like cells, it did not include cells with a propensity to develop into tumors. The team was able to reproduce their method with very similar results using two stem cell lines generated decades apart by two different laboratories using different techniques.
As a part of the study, an animal model was injected with 9- and 11-day-old cardiovascular precursor cells into damaged heart tissue. It was found that these precursor cells differentiated into cardiac muscle fiber bundles that survived in the heart for at least 12 weeks; with improved heart functions. “These results suggest a role for the use of laminins in cardiac muscle cell differentiation, and may lead the development of clinical-quality cardiovascular progenitor cells for regenerative cardiology in humans,” said Prof Tryggvason. However, further research is required to investigate the cell subpopulations that form with this technique to explore whether they can intensify new heart muscle growth in living animals.