Macrophage

Definition

Macrophages are large white blood cells that are essential components of the innate immune system. They engulf and digest cellular debris, pathogens, and other harmful substances through a process known as phagocytosis.

5 Must Know Facts For Your Next Test

1. Macrophages originate from monocytes, which differentiate into macrophages when they migrate into tissues.
2. They play a crucial role in both initiating inflammation and resolving it by clearing dead cells and pathogens.
3. Macrophages can present antigens to T cells, linking innate and adaptive immunity.
4. They release cytokines that signal other immune cells to respond to the site of infection or injury.
5. Macrophages have specialized forms in different tissues, such as Kupffer cells in the liver and alveolar macrophages in the lungs.

Related terms

Phagocytosis:

The process by which a cell engulfs particles such as bacteria or cellular debris.

Monocyte: A type of white blood cell that differentiates into macrophages or dendritic cells upon entering tissues.

Cytokine: Small proteins released by cells that have a specific effect on interactions and communications between cells during immune responses.