Which immune cells are capable of engulfing anything from E. coli to little plastic beads?

Which immune cells are capable of engulfing anything from E. coli to little plastic beads?

• A. T helper cells
• B. B cells
• C. Natural killer cells
• D. Macrophages

Answer: (D)

Phagocytosis—the ability to engulf and digest particles—is a key function of certain immune cells. Among these, macrophages are professional phagocytes that patrol tissues and can ingest a wide range of targets, from bacteria like E. coli to small plastic beads. Their versatility in engulfing particles of varying sizes and compositions makes them central to the innate response and to initiating the later adaptive response by processing and presenting pieces of what they eat to other immune cells. In contrast, T helper cells and B cells are primarily involved in coordinating and producing antibodies, not in eating particles, and natural killer cells destroy infected or abnormal cells without phagocytosing large objects. So the cell best described as capable of engulfing both bacteria and beads is the macrophage.

Phagocytosis—the ability to engulf and digest particles—is a key function of certain immune cells. Among these, macrophages are professional phagocytes that patrol tissues and can ingest a wide range of targets, from bacteria like E. coli to small plastic beads. Their versatility in engulfing particles of varying sizes and compositions makes them central to the innate response and to initiating the later adaptive response by processing and presenting pieces of what they eat to other immune cells. In contrast, T helper cells and B cells are primarily involved in coordinating and producing antibodies, not in eating particles, and natural killer cells destroy infected or abnormal cells without phagocytosing large objects. So the cell best described as capable of engulfing both bacteria and beads is the macrophage.