American Board of Surgery Qualifying Exam (ABS QE) Practice Test

Which cells are the most important for wound healing?

1. Neutrophils

2. Eosinophils

3. Macrophages

4. Fibroblasts

The correct answer is: Macrophages

Macrophages play a crucial role in the wound healing process due to their multifaceted functions. After an injury, these cells are among the first responders that migrate to the site of tissue damage. They are pivotal in the inflammatory phase of healing, where they help to clear debris, dead cells, and pathogens through phagocytosis. Beyond their role in clearing the wound, macrophages also secrete a wide variety of cytokines and growth factors that are essential for orchestrating the healing process. They stimulate the recruitment and activation of other immune cells, promote angiogenesis (the formation of new blood vessels), and are key players in signaling pathways that lead to tissue repair and regeneration. Furthermore, macrophages assist in transitioning the wound from the inflammatory phase to the proliferative phase, where fibroblasts and endothelial cells proliferate and migrate to the wound site. While neutrophils and eosinophils play roles in the immune response, and fibroblasts are important in the synthesis of extracellular matrix and collagen during tissue repair, it is the macrophages that integrate these processes and facilitate effective healing. Their ability to modulate the immune response and support cellular functions makes them the most important cells in wound healing.