What is a phagocytic receptor?

Receptors for phagocytosis can be divided into two categories by recognised molecules. The first, opsonic receptors, are dependent on opsonins. Among these are receptors that recognise the Fc part of bound IgG antibodies, deposited complement or receptors, that recognise other opsonins of cell or plasma origin.

What are the receptors on macrophages?

The major chemokine receptors on macrophages are CCR2, CCR5, and CX3CR1 (130, 131). CCR2 binds CCL2 and related chemokines of the MCP subfamily and is responsible for release of monocytes from the bone marrow and their trafficking to inflamed tissues.

What are phagocytic macrophages?

Macrophages are effector cells of the innate immune system that phagocytose bacteria and secrete both pro-inflammatory and antimicrobial mediators. In addition, macrophages play an important role in eliminating diseased and damaged cells through their programmed cell death.

How do macrophages perform phagocytosis?

The macrophage starts to surround the virus and engulf it into the cell. Instead of moving the large item across the plasma membrane, which might damage the membrane permanently, phagocytosis uses extensions of the cytoplasm (pseudopods) to surround the particle and enclose it in a membrane.

What is the difference between phagocytes and macrophages?

Macrophage is a type of white blood cell which is a phagocyte. They are scavengers which constantly move around to remove dead cells and foreign bodies such as pathogenic microbes; this occurs by the production of compounds such as nitric oxide.

How do macrophages detect antigens?

Adaptive immunity Another function of macrophages is to alert the immune system to microbial invasion. After ingesting a microbe, a macrophage presents a protein on its cell surface called an antigen, which signals the presence of the antigen to a corresponding T helper cell.

What is the main purpose of phagocytosis?

Phagocytosis is a cellular process for ingesting and eliminating particles larger than 0.5 μm in diameter, including microorganisms, foreign substances, and apoptotic cells. Phagocytosis is found in many types of cells and it is, in consequence an essential process for tissue homeostasis.

What cells perform phagocytosis?

Several types of cells of the immune system perform phagocytosis, such as neutrophils, macrophages, dendritic cells, and B lymphocytes. The act of phagocytizing pathogenic or foreign particles allows cells of the immune system to know what they are fighting against.