A macrophage is a cell from big size which can engulf various particles and destroy microorganisms. It is a kind of White blood cell or White blood cell It also promotes the action of other types of cells of the immune system and eliminates dead cells.

They defend the organism

Before moving on, it is important to mention that white blood cells are blood cells, like the Red blood cells and the platelets. Among the white blood cells we find macrophages, basophils, monocytes, neutrophils, lymphocytes and other cells.

Macrophage cell

Macrophages are cells capable of engulfing particles and destroying microorganisms

Returning to the idea of ​​macrophage, they arise as a response to the accumulation of dead cells or a Infective process. They are formed from monocytes, when these leave the blood circulation and join an organ or tissue, then registering various changes until they become macrophages.

With a diameter of about 21 microns, macrophages can recognize, engulf and destroy those elements that are their objective. That is why they are very relevant in the defense of the organism.

When digesting a microbe, the macrophage shows the antigen on its surface. In this way it alerts the rest of the leukocytes that there is, precisely, a antigen. After this warning, there is a multiplication of white blood cells that respond to the pathogen.


It is the most important function of macrophages, as mentioned above, which can be described as the action of surround foreign bodies that enter the body with their own membrane. Among these bodies are the waste and bacteria of certain tissues. There are more cells that fall into the category of phagocytes, how to be the neutrophils.

One of the capabilities of macrophages is the chemotaxis, so can be attracted and drawn to a particular location where there is a concentration of certain chemicals. East phenomenon it can occur in the presence of thrombin, interleukin-I, collagen fragments, kallikrein, fibronectin, leukotrienes, immunoglobulins and elastin, among others.

The inflammation

Macrophages belong to the group of innate components of the immune system. In other words, their response to the presence of microorganisms is natural. Among the recipients of membrane that express for the various bacterial molecules are the following: for mannoses, for carbohydrates and for lipopolysaccharides.

In vertebrates and invertebrates, macrophages are part of the immune response to infectious processes, because of having its receptors known as sweepers, which have an important specificity to ligands (ions or molecules attached to a central metal atom), such as proteins, lipoproteins, oligonucleotides, phospholipids and anionic polysaccharides.

Presentation of antigens

The moment a macrophage phagocytes a microorganism, it processes and locates its antigens on the outside of its cell membrane. There the recognition of the same by the helper T lymphocytes. Next, the T cells generate lymphokines for the activation of B. For this reason, macrophages are considered antigen presenting cells

Leukocyte macrophage

It is a class of leukocyte that activates the immune system and eliminates dead cells

Repair and hemostasis

The macrophage is capable of ingesting dead cells belonging to the organism in which it is housed. Secondly, repairs damaged tissues after the immune reaction. It can also perform the series of mechanisms that are called hemostasis, which consists of generating certain substances to carry out the coagulation, such as thrombomodulin, factors VII and XIII, protein C and factor III.

For zoology

In the field of zoology, on the other hand, macrophages are animals that eat large prey compared to their own build. These species usually have the ability to dislocate their jaws to ingest the entire body of the prey and also have a suitable structure for swallowing it.