Living organisms respond to pathogens by mobilizing their own general processes, without resorting to designed apparatus.
It is the immune network, a network of chemical and cellular mediators that are activated in defense of the organism in case of insults of different types such as chemical, physical, bacterial and viral ones.
The typical biological expressions of this defensive strategy are represented by innate immunity and acquired immunity.
The first has a non-specific character and manifests itself in an articulated sequence of humoral, cellular and vascular events. Inflammation is a typical example, with manifestations attributable to well-known symptoms such as calor, rubor, tumor, dolor and functio lesa.
"It is the immune network, a network of chemical and cellular mediators that are activated in defense of the organism"
The humoral response of inflammation is carried out by the derivatives of arachidonic acid, prostaglandins and leukotrienes, physiological mediators involved in the normal functioning of the organism but which are hyperactivated in conditions of inflammation.
From an evolutionary perspective this is an older level of the immune system, made up of biological barriers, cells and mediators that activate a first line of defense against aggression.
Acquired or adaptive immunity concerns only our immune system which, in the course of its evolutionary history, has learned to distinguish and separate the self from the non-self, everything that belongs to the composition of the organism from what is foreign to it.
A malfunction of this specific recognition mechanism is at the basis of autoimmune diseases, in which the immune system activates defense mechanisms against its own elements, causing an alteration and damage to the affected area.
This level of the immune system is made up of the cells of the lymphoid line, the T and B lymphocytes.
The former have the task of eradicating infections and activating other cells, including macrophages and B lymphocytes in addition to an effector function, lymphocytes are also responsible for immunological memory, at the basis of Burnet's "theory of clonal selection".
"Collagen, the main protein of the animal kingdom, has also been shown to be particularly"
Furthermore, the immune system has physiological regulation mechanisms based on hormones and other elements capable of acting as immunomodulators, altering the sensitivity of our defense network.
The interconnection between T lymphocytes and vitamin D is an example. Their bond is essential for the fulfillment of their defensive functions. For this reason, it is believed that hypovitaminosis dictated by anagraphic or malnutrition reasons may be responsible for the weakening of the immune response in the elderly.
Collagen, the main protein of the animal kingdom, has also been shown to be particularly active in the chemotactic stimulation of monocytes; these are voluminous white blood cells which, following chemotactic and inflammatory stimuli, reach the vascular compartment and, from this, the tissue, where they mature into macrophages or in dendritic cells; the main function of macrophages and dendritic cells is to phagocytize, that is to incorporate in their cytoplasm foreign particles, including microorganisms, and finally destroy them.