Immune System and T-Cell Receptor Dynamics of a T-Cell Population

Abstract

Figure 2.1 presents the two parts of the immune system [33]. The Innate immune system is made of cells and molecules that are genetically encoded and co-evolve with pathogens¹. It is inherited as such and it represents the first line of the organism defense. It can recognize some pathogen, such as virus or bacterium,

and remove them within several hours. However, the diversity of pathogens it can recognize is limited and some pathogen can escape the defenses of the innate immune system. Then the pathogens are faced with the response of the adaptive immune system. The adaptive part is able to recognize a larger diversity of possible antigen² carried by pathogen. During the invasion phase the population of pathogen increases. The adaptive immune system is programmed to recognize the antigen and produce enough effector cells, specific to the pathogen, to suppress and eliminate the pathogen population. That process typically takes several days. During this time, the pathogen could be causing considerable harm, and that is why the innate immunity is so essential.

Pathogen - any disease-producing agent (especially a virus or bacterium or other microorganism) [22].

Antigen - any substance (as a toxin or enzyme) that stimulates an immune response in the body (especially the production of antibodies) [22]. In our context, piece of protein constituting a pathogen.