Which of the following cells are involved in the process of “efferocytosis”?
**Core Concept**
Efferocytosis is a process by which apoptotic or necrotic cells are engulfed and removed by phagocytic cells, thereby maintaining tissue homeostasis and preventing inflammation. This process involves the coordinated action of various cell types, including macrophages and other phagocytes.
**Why the Correct Answer is Right**
Efferocytosis is primarily mediated by macrophages, which express specific receptors such as CD36 and SR-A (scavenger receptor A) that recognize and bind to the phosphatidylserine exposed on the surface of apoptotic cells. This binding triggers the engulfment of the apoptotic cell by the macrophage, which then undergoes a process of cellular digestion and recycling. Other cell types, such as dendritic cells and neutrophils, may also participate in efferocytosis, particularly in specific tissue environments.
**Why Each Wrong Option is Incorrect**
**Option A:** While dendritic cells are antigen-presenting cells, they are not primarily involved in efferocytosis. Dendritic cells are more focused on processing and presenting antigens to T-cells.
**Option B:** Neutrophils are phagocytic cells, but they are not the primary cells involved in efferocytosis. Neutrophils are more focused on combating infections and inflammation.
**Option C:** While monocytes are a type of phagocytic cell, they are not specifically involved in efferocytosis. Monocytes are more focused on maturing into macrophages or dendritic cells.
**Clinical Pearl / High-Yield Fact**
Efferocytosis is crucial for maintaining tissue homeostasis and preventing chronic inflammation. Dysregulation of efferocytosis has been implicated in various diseases, including atherosclerosis, cancer, and autoimmune disorders.
**Correct Answer:** C. Macrophages.