When one experiences a heart attack, it is not certain whether they will fully recover or not. Even if the survivor goes back to his regular life, physical restrictions might be necessary due to heart scarring that occurs after the attack.
Immune system friendly
Bioengineers and surgeons from Rice University and Baylor College of Medicine (BCM) have developed a biomaterial containing stem cells to help repair the heart tissue damage that forms after a heart attack.
The research was published in the journal Biomaterials Science.
In fact, stem cells have been used to try and repair the heart tissue that was damaged before. A type of adult stem cell produced in blood marrow called mesenchymal stem cells (MSCs) was considered helpful in tissue repair. However, the immune system combatted them.
They thought the cells alone were not to correspond to the immune system.
"The immune system perceives them as foreign. And so very rapidly, the immune system starts chewing at them and clearing them out." said Omid Veiseh, one of the research leaders.
First trial on rodents
So basically what they did was to coat the stem cells with a biocompatible hydrogel capsule made of brown algae. Next, they were put in rodents, next to scarred tissue of their hearts. At the end of four weeks, the rodents with shielded stem cells healed 2.5 times better and faster compared to those with non-shielded stem cells.
Samira Aghlara-Fotovat, a graduate student and co-author of the study working in Veiseh's lab, generated 0,05-inch (1.5-millimeter) capsules that each contained around 30,000 MSCs.
"The immune system doesn't recognize our hydrogels as foreign, and doesn't initiate a reaction against the hydrogel," Veiseh added.
In fact, regulations of scarred tissues are operated by a protein called "type 5 collagen." So if one lacks the mentioned collagen or has it in small levels, it is likely that damaged tissue will have a hard time being repaired.
Have the capsules been tried on humans yet? Unfortunately, they haven't. But the thing is that encapsulation technologies designed to be compatible with immune system are already being developed for chronic diseases at Sigilon Therapeutics, a Cambridge, Massachusetts-based biotech company. So it is a promising development that most probably will be used on humans soon.