Radiation immunology

Radiation immunology studies the effect of ionizing radiation on the immune system. More radiation immunology investigates violations and the means of restoring antimicrobial immunity, specific features of interaction of irradiated organism with microbes, the role of infectious complications and autoimmune mechanisms in pathogenesis, treatment and outcome of radiation sickness, radiation effect on transplantation immunity, problems related to the so-called radiation chimeras, with the possibility of overcoming biological incompatibility in the irradiated organism, with the use of cell transplantation of hematopoietic organs for treatment of radiation sickness (see).
Action of ionizing radiation on the immune reactivity is manifested in sharp oppression of the main mechanisms of immunity. Increases the permeability of biological barriers, reduced bactericidal activity of blood and tissue, decreases the phagocytic activity of cells, sharply oppressed education antibodies. In acute radiation sickness of the body is actually unarmed not only in front of pathogenic and conditionally pathogenic microorganisms. The constant companion of radiation sickness is endogenous infection with bacteremia due to microbial inhabitants of bowels, respiratory tract and other Direct cause of death of irradiated organism is often autoinfection. Exogenous infectious diseases occur very hard, are characterized by a generalization of the process and the accumulation of pathogens in the tissues. Prevention and treatment of infectious complications is an essential event in the integrated treatment of radiation sickness.
In the result of the action of radiation on cells and tissues change their antigenic properties. This circumstance and circulation tissue antigens in the blood lead to the appearance of antibodies and to autouniversal. However, the value of autoimmune mechanism in the overall picture of the radiation damage has not yet been elucidated.
Radiation immunology also deals with issues of transplantation immunity. Irradiation, oppressing transplantation immunity, provides engraftment and reproduction transplanted from a donor cells of the blood-forming organs. However, due to immunological competence of hematopoietic tissues may occur immunological reaction of the transplanted cells against the host cells ("graft versus host"). This explains the development of 4-8 weeks after transplantation "secondary disease, which manifests itself in animals dermatitis, loss of hair, depletion, leading to the deaths. Man of "secondary disease" has similar symptoms. Many researchers believe the likely reaction by owner against graft". Radiation immunology finds means to prevent the development of secondary disease", which is important not only for the treatment of radiation sickness, but also more broadly to solve biological tissue incompatibility.