A study led by Maria Carmo-Fonseca at GIMM has helped clarify one of the main limitations of lab-grown heart cells, which are widely used around the world to study heart disease and test new drugs. Although these cells make it possible to investigate the human heart without invasive procedures or animal models, they still fail to fully reproduce the characteristics of real heart cells, which can compromise the accuracy of certain studies.
"These cells are extraordinarily useful, but they still behave like very immature cells", explains the researcher. "We wanted to understand exactly what is missing for them to reach the same level of development as cells in a human heart".
The study, published today in the journal Stem Cell Reports, presents for the first time a detailed portrait of how the human heart evolves from early developmental stages to adulthood. By analysing this natural process, the researchers compared - at an unprecedented level of detail - the behaviour of human heart cells with that of cells created in the laboratory from stem cells.
The team discovered that lab-grown heart cells become stuck in an immature stage and fail to complete several fundamental steps that occur during the development of the real human heart. They identified alterations in essential mechanisms of cellular function that are responsible for correctly activating and coordinating genetic instructions.
"We found very clear differences in processes that are fundamental for a heart cell to function as such", says Maria Carmo-Fonseca. "Knowing exactly where these differences lie allows us to begin correcting them".
Based on these findings, the research group developed a reference map that describes in detail how human heart cells change throughout development. This map serves as a benchmark, enabling scientists to assess whether lab-grown heart cells are developing properly or still display overly immature characteristics.
This new reference will help researchers worldwide improve the models used to study heart disease, making them more realistic and increasing the reliability of tests performed with these cells.
"Essentially, we created a guide that shows what is right and what is still missing in lab-grown heart cells", explains Maria Carmo-Fonseca. "This makes it possible to determine whether a cell is truly ready to be used as a disease model. The ultimate goal is for these models to be as close as possible to the human heart, so that we can develop better therapies".
The advance opens the door to more rigorous research and more effective treatments in the future, particularly in the field of precision cardiology.