Is phagocytosis intracellular killing?

Phagocytosis and bacterial killing. Neutrophils are specialized in ingestion and intracellular killing of a large array of different bacteria, yeasts, fungi, mycoplasmas, and perhaps also viruses. Most microorganisms can only be phagocytosed after opsonization with specific antibodies and/or complement fragments.

How do the intracellular bacteria evade phagocytic death?

The role of bacterial capsules in avoiding phagocytosis may be its ability to “hide” opsonically active molecules on the bacterial cell wall. The cell wall of S. aureus contains abundant C3b after incubation in normal human serum but specific anticapsular antibodies are necessary for phagocytosis.

What happens to cells after phagocytosis?

The cell flows around the object until it has been completely engulfed. The engulfed object is thus enclosed within a membrane-bound vacuole called a phagosome. The phagocyte digests the ingested particle with hydrolytic enzymes, which are contained within membrane-enclosed sacs called lysosomes found within the cell.

How do lymphocytes destroy bacteria?

Lymphocytes’ role in this is to fight infections by producing antibodies, which are chemicals that help your body stop and then remove foreign invaders such as bacteria, viruses, fungi, parasites, and toxic chemicals.

How do some bacteria avoid destruction after they have been engulfed by phagocytic cells through phagocytosis?

Some bacteria resist phagocytic destruction by preventing fusion of the lysosome with the phagosome. Some bacteria resist phagocytic destruction by resisting killing by lysosomal chemicals. Some bacteria resist phagocytic destruction by killing phagocytes.

What is the immune response to intracellular pathogens?

In the case of infection by intracellular bacteria, they have the ability to survive and replicate within phagocytic cells, which causes the circulating antibodies to be inaccessible to intracellular bacteria. The innate immune response against these bacteria is mediated primarily by phagocytes and NK cells [180].

How are antigens removed from bacteria?

The antibodies destroy the antigen (pathogen) which is then engulfed and digested by macrophages. White blood cells can also produce chemicals called antitoxins which destroy the toxins (poisons) some bacteria produce when they have invaded the body.