The immune system plays an important role in the heart’s response to injury. But until recently, conflicting data made it difficult to distinguish the immune factors that encourage the heart to heal following a heart attack, versus those factors that can lead to further damage. (Read more)
Now, research performed by Dr. Slava Epelman and colleagues at Washington University School of Medicine in St. Louis have shown that two major pools of immune cells are at work in the heart. Both belong to a class of cells known as macrophages. One appears to promote healing, while the other likely drives inflammation, which is detrimental to long-term heart function. “Macrophages have long been thought of as a single type of cell,” said first author Slava Epelman, instructor in medicine. “Our study shows there actually are many different types of macrophages that originate in different places in the body. Some are protective and can help blood vessels grow and regenerate tissue. Others are inflammatory and can contribute to damage.” The research is published in the Cell Press journal Immunity (2014; 40: 90-104).