During which phase do neutrophils and macrophages arrive at the damage site?

During which phase do neutrophils and macrophages arrive at the damage site?

• A. Leukocyte migration
• B. Phagocytosis
• C. Metabolic changes
• D. Chronic inflammation

Answer: (A)

The main idea is how immune cells reach a damaged area during inflammation. Neutrophils and macrophages arrive at the site during leukocyte migration, the process by which circulating white blood cells exit the bloodstream and move into tissue in response to chemotactic signals from the injured area. Neutrophils are among the first to arrive, rolling along the endothelium, adhering, and crossing into tissue (diapedesis) in response to chemokines. Monocytes then exit the bloodstream and differentiate into macrophages in the tissue, contributing to this migratory phase as well. Once at the site, these cells carry out actions like phagocytosis to engulf pathogens and debris, but the arrival itself is governed by leukocyte migration. Metabolic changes refer to intracellular activation, not the recruitment phase, and chronic inflammation describes a later or ongoing inflammatory state rather than the initial arrival of these cells.

The main idea is how immune cells reach a damaged area during inflammation. Neutrophils and macrophages arrive at the site during leukocyte migration, the process by which circulating white blood cells exit the bloodstream and move into tissue in response to chemotactic signals from the injured area. Neutrophils are among the first to arrive, rolling along the endothelium, adhering, and crossing into tissue (diapedesis) in response to chemokines. Monocytes then exit the bloodstream and differentiate into macrophages in the tissue, contributing to this migratory phase as well. Once at the site, these cells carry out actions like phagocytosis to engulf pathogens and debris, but the arrival itself is governed by leukocyte migration. Metabolic changes refer to intracellular activation, not the recruitment phase, and chronic inflammation describes a later or ongoing inflammatory state rather than the initial arrival of these cells.