El sistema inmune y su función en el sistema nervioso central

Abstract

The immune response is a set of mechanisms designed to defend our body from the numerous microorganisms to which we are continually exposed. The immune response is organized in several phases. The first phase is composed of several barriers which avoid the entrance of pathogens. In the second phase, secretion of signals induce inflammation to attract cells of the immune system (IS) to fight against the pathogen. Phagocytosis is one of the mechanisms to eliminate the pathogens, but at the same time is a warning signal for other cell types, such as T and B lymphocytes. T and B lymphocytes recognize the pathogens with very specific receptors. As a consequence, lymphocytes form a specialized clone army to fight the pathogen. Occasionally, the IS is engaged by damage signals alone, without the presence of pathogens. The final phase involves tissue repair and regeneration. Within the central nervous system (CNS), the IS works in a particular way. The nervous tissue is composed of neurons and glia cells. Glia cells are essential for the correct neuronal functioning. Microglia cells are a variety of glia cells that belong to the IS of the brain. They are phagocytes that normally ingest death cells debris, but when there is severe tissue injury, they engage an inflammatory response that may result in neuronal damage