... The Immune SystemAImune systemis a collection of biological processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents such as viruses or parasitic infestation of worms, and needs to distinguish harmful agents from the body's own healthy cells as well as tissues to function properly. Detection is complicated because pathogens can evolve rapidly, producing adaptations to avoid the immune system and allowing pathogens to successfully infect their hosts. To survive this challenge, multiple mechanisms evolve and recognize and are able to neutralize pathogens. Even single-celled organisms like bacteria have enzyme systems that protect against viral infections. Other underlying immune mechanisms have evolved in the old eukaryotesand remained in their modern descendants as plants, fish, reptiles and insects. These mechanisms include antimicrobial peptides called defensins, phagocytosis, and the complement system. Vertebrates like humans have even more sophisticated defense mechanisms. The vertebrate immune system consists of many types of proteins, cells, organs and tissues that interact in an elaborate dynamic network. As part of this more complex immune response, the human immune system adapts over time to recognize specific pathogens more efficiently. This adaptation process is referred to as "adaptive immunity" or "acquired immunity" and creates immune memory. Immune memory is created from a primary response to a specific pathogen, and provides an improved response to secondary encounters with that particular pathogen. This acquired immunity process is the basis of vaccination. Disorders of the immune system can result in disease. Immunodeficiency occurs when the immune system is less active than it normally is, resulting in recurrent and life-threatening infections. Immunodeficiency may be the result of a genetic disease such as severe immunodeficiency combined or being produced by pharmacists or an infection such as acquired immunodeficiency syndrome (AIDS) that is caused by the HIV retrovirus. In contrast, autoimmune diseases result from a hyperactive immune system that attacks normal tissues, as if they were foreign organisms. Common autoimmune diseases include Hashimoto's thyroiditis, rheumatoid arthritis, diabetes mellitus type 1, and systemic lupus erythematosus. Immunology encompasses the study of all aspects of the immune system that have great relevance to human health in disease prevention and containment. Further research in this field is expected to play a very important role in promoting health and treating diseases for the whole of humanity. This text uses material fromWikipedia, Licensed underCC BY-SA The memory of the human immune system is critical for the development of vaccines. Only if the body is capable of recognizing a pathogen with which already contacted in the case of a second infection, the immune system is able to combat more effectively than did the first time. Prof. imunobiologista Dr Wolfgang Schamel III Biology Institute University of Freiburg, And his colleagues were able to demonstrate how the memory of the immune system exerts its functions. Their findings have now been published in the journalsimmunity, and Journal of Biological Chemistry (JBC). The immune system becomes familiar with a pathogen during an initial infection and understands that it must be combated. When T-cell receptors in the immune system reach the same pathogen a second time, they are much more sensitive to them than during the first encounter, and so it takes less to activate the immune system topathogens. There was a need to clarify why these receptors become more sensitive. In 2011, the research group and Schamel a team led by Prof. Dr. Balbino Alarcon of the Autonomous University of Madrid, Spain, has found the answer to this fundamental question. In a publication in the official journal of immunity, they showed that the increase in sensitivity is caused by a grouping ofCells Treceiving: In a naive cell not yet "found with the pathogen," the receivers are arranged individually incell membrane, pathogens so that the immune system reacts quickly. In a cell called a memory cell that resembles the pathogen, the receptors are arranged in clusters on the membrane. When a pathogen binds to a receptor in a group, all receptors within the group are activated simultaneously. Thus, a large number of receptors need to be confronted with a large number of pathological agents in order to make it "well trained". ThisImmune systemstaymore sensitive. Now, as reported in the journal JBC, a team of researchers in Freiburg under Schamel and Prof. Dr Rolf Schubert, Professor of Pharmaceutical Technology and Biopharmacy at the Institute of Pharmaceutical Sciences at the University of Freiburg, have demonstrated how a cell forms these groups of receptors. The critical factors for the success of this effort were the results of Schamel's T-biochemistry research experiment withcell receptorsAnd Schubert's experience in the production of extracellular liposomes.
Dr. Eszter Molnár, a Schamel postdoctoral researcher, and Dr. Martin Holzer of Schubert's research group isolated the receptors and rebuilt the model on a synthetic membrane. After a year and a half of work, the scientists made a breakthrough: They discovered that the composition of the lipids of a membrane is responsible for the organization groupsreceptors.
The collaboration between the two teams was made possible thanks to a project funded by the Center for Studies and Biological Signalling BIOSs, A group of excellence at the University of Freiburg.
The lipid composition of the cell of a "naive" (Translator's Note: Naive this theme is an immune system that has never been confronted, for example, the measles virus, everyone knows that, in general, only have measles once in your life, when you lose this naiveté) differs from a memory cell. Cholesterol is the key factor in this process, as it is present in high concentrations in amemory cell.This higher concentration of cholesterol leads to aggregation of receptors, because cholesterol joins the like glue.
Schamel and Schubert are members of the group of excellence of the Center for Studies and Biological Signaling Freiburg BIOSs. Schamel is also a member of Apemann Graduate School of Biology and Medicine and the Center for the Freiburg University Medical Center Chronic Immunodeficiency and director of the EU network Sybilla, who also supported this project.
Journal reference:Immunity Journal of Biological Chemistry