1. Recognition: The white blood cell's surface receptors, including those for glycoproteins, recognize molecules on the bacteria's surface as "non-self." This could be due to specific bacterial antigens, like lipopolysaccharides (LPS), or other unique structures.
2. Adhesion: Once recognized, the white blood cell adheres to the bacteria.
3. Engulfment: The white blood cell extends its cell membrane, forming pseudopods (false feet) that surround and enclose the bacteria. This forms a phagosome, a vesicle containing the bacteria within the cell.
4. Fusion: The phagosome fuses with a lysosome, a cellular organelle containing powerful digestive enzymes.
5. Destruction: The lysosomal enzymes break down the bacteria's cell wall, proteins, and other components, effectively destroying it.
Key Players:
* Phagocytes: The main white blood cells responsible for phagocytosis include neutrophils, macrophages, and dendritic cells.
* Glycoproteins: These are proteins with sugars attached, acting as receptors on the surface of white blood cells to recognize foreign invaders.
* Lysosomes: Organelles within white blood cells that contain enzymes for breaking down foreign material.
In summary, white blood cells use a combination of recognition, adhesion, engulfment, fusion, and destruction to effectively eliminate bacteria that they identify as "non-self" through glycoprotein recognition and other mechanisms.
