Аудармасы

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1, 1) Immune response, or immunological reactivity, is a highly specific form of the body's response to foreign substances (antigens). When the immune response detection occurs alien agent and its elimination. With the introduction of the antigen occurs the primary immune response after about 2 days in blood, form antibodies, the titer of which is increasing, reaches a maximum (4-6-th day) and then falls. Secondary immune response occurs on re-introduction of the same antigen and is characterized by a higher and more rapid increase in antibody titer. Such a reaction strengthened the formation of antibodies on repeated administration of the antigen, as you know, is called immunological memory due to the presence of cells and immunological memory may persist for months and even years. The immune response depends on the genotype of the organism.

The immune response to infection. First, the antigen is captured by (I) presenting cell (macrophage). Inside the macrophage, the antigen is processed (processing of antigen) and falls on its surface (2). Antigen on the surface of the macrophage recognize activated T-helper (3). T-suppressor cells in the immune response interact with T-helper cells and b-lymphocytes. T-helper activates the lymphocyte, the surface of which is processional-tion antigen (4). B-lymphocytes on their surface have re-datory immunoglobulins, which they recognize and bind circulating in the body, the antigen (5). Activated b-lymphocytes proliferate and transform into a clone of plasma cells (b), and some of their descendants become memory cells (7), providing a rapid response to infection in the future. A clone of plasma cells produces antibodies that bind to the antigen and mark it (8), antigens are recognized and destroyed by macrophages (9).

Аудармасы

При вирусной инфекции ДНК или РНК вируса попадает в клетку, а вирусные белки остаются на клеточной

Цитотоксические Т-клетки (Т-киллеры) своими рецепторами специфически узнают вирусные антигены только в комбинации с белком -главного комплекса гйстосовместимости (МНС) класса I, которые имеются почти на всех клетках организма. МНС класса I определяют иммунологическую индивидуальность клетки. В отличие от антител Т-рецепторы не узнают и не связывают антиген, если тот не находится вместе с белком МНС. После узнавания антигенов цитотоксические Т-клетки убивают зараженные вирусом клетки.

Мутации любых локусов, обусловливающие разные звенья иммунной системы организма, в той или иной степени влияют на иммунный ответ. У кроликов, свиней, птицы, мышей и т. д. обнаружены индивидуальные и межлинейные различия по силе иммунного ответа.

Dysregulation of immune response leads to many diseases, especially allergic, susceptibility to which depends on the genotype of the organism.

Иммунный ответ, или иммунологическая реактивность, — высокоспецифическая форма реакции организма на чужеродные вещества (антигены). При иммунном ответе происходят распознавание чужеродного агента и его элиминация. При введении антигена возникает первичный иммунный ответ — приблизительно через 2 дня в крови образуются антитела, титр которых возрастает, достигает максимума (к 4—6-му дню), а затем падает. Вторичный иммунный ответ возникает на повторное введение того же антигена и характеризуется более высоким и быстрым нарастанием титра антител. Подобная реакция более усиленного образования антител на повторное введение антигена, как вы знаете, называется иммунологической памятью, обусловлена наличием клеток иммунологической памяти и может сохраняться в течение многих месяцев и даже лет. Иммунный ответ зависит от генотипа организма.

Иммунный ответ на инфекцию в общем виде показан на рисунке 53. Сначала антиген захватывается (I) представляющей клеткой (макрофагом). Внутри макрофага антиген перерабатывается (процессинг антигена) и попадает на его поверхность (2). Антиген на поверхности макрофага узнает активированный Т-хелпер (3). Т-супрессоры при иммунном ответе взаимодействуют с Т-хелперами и В-лимфоцитами. Т-хелпер активирует В-лимфоцит, на поверхности которого находится процессирован-ный антиген (4). В-лимфоциты на своей поверхности имеют ре-депторы-иммуноглобулины, которыми они узнают и связывают циркулирующий в организме антиген (5). Активированные В-лимфоциты пролиферируют и превращаются в клон плазматических клеток (б), а некоторые из их потомков становятся клетками памяти (7), обеспечивающими быстрый ответ на инфекцию в будущем. Клон плазматических клеток продуцирует антитела, которые связываются с антигеном, маркируют его (8), антигены узнаются и уничтожаются макрофагами (9).

1. 2) Genetic control of variable regions. So far, we have considered the genetic control of only constant regions that can be satisfactorily explained in terms of representations of classical genetics. However, this approach is not suitable for variable regions. How to explain that all of the amino acid sequence of variable regions analyzed so far turned out to be different, we Can assume that anyone has a very large number of clones of plasma cells, each of which forms with the structure of immunoglobulin variable part specific only to this clone. It is also possible that the specificity of antibodies is determined by its variable region. In this case left open two fundamental questions.

Biosynthesis of antibodies is carried out In cells that interact with T-lymphocytes. Antigen binds to receptors on the surface as b-and T-lymphocytes, after which T-lympho-op allows In-cell synthesis of immunoglobulins, i. e. antibodies. Amazes the ability of lymphocytes to respond to an enormous number of antigens and to remember each of them so that when they re ingested effectively produced immunoglobulins bind specifically to this antigen. Genetic control of immune response studying an area of genetics called immunogenetics.

GII began with dinitroaniline connections. DNCB and its analogues used for epicutaneous sensitization, and complex antigens composed of protein, peptide or amino acid with a DNF, and was injected into the pads of the paws of Guinea pigs with Freund adjuvant [147]. These studies are of great value for study of Allergy to chemicals in General, as it is on the model of sensitization to DNP-groups started the development of such important issues as the study of primary mechanisms of contact Allergy, the role of hapten and carrier in the induction and suppression of allergic reactions, the mechanism of formation of complex antigens, tolerance to chemicals, immunological characteristics anticapting antibodies, the morphology of skin reactions of delayed type, genetic control of immune response, etc. Dinitroaniline antigens are widely used in theoretical immunological studies and currently, along with artificial antigens a polymer of amino acid residues

The immune response is a chain of molecular and cellular events that begins in the body with recognition of foreign antigens and ending with the accumulation of immune effector cells and antibodies. The team interacting in the immune response of the cells consists of three major classes-lymphocytes, T-lymphocytes and macrophages. Antibody synthesis is carried out by b lymphocytes, T cells — helper cells — help b-cells to synthesize antibodies to T-dependent antigens. Antigens, causing synthesis of the antibody with the essential participation of T lymphocytes, called thymus-dependent or T-dependent. In most cases, cooperation of T - and b-cells is a necessary condition for the immune response. Genetic control of immune response is through T cells. Cells of the third type macrophages or cells that cooperate with T and b-lymphocytes. Macrophages capture antigens trapped in the body, resulting on the surface of macrophage produced a kind of clip with antigenic molecules, oriented with their deter-minontime areas outside. This clip provides the corresponding macrophage b-lymphocyte surface protein receptors which bind with antigenic determinants. This way-lymphocyte gets a specific signal, which requires him to begin to multiply and produce antibodies. The second signal is nonspecific — may originate from T-lymphocytes, activated by other antigen or mitogen.

Immune response, like all biological function, is controlled by diverse regulatory mechanisms. These mechanisms ensure the recovery of the original, inactive condition of the immune system when the immune response to the antigen is no longer required. Effective immune response is the result of the interaction between antigen and a network of immuno-competent cells. The nature of the immune response, both in quantitative and qualitative against, depends on many factors, including the type of antigen, its dose and routes of entry, from the properties of antigen-presenting cells (APC) and genetic characteristics of the organism, as well as from previous contact of the immune system with this or perekrestnaya antigen. The immune response can influence specific antibody. Some of these regulatory factors are considered in detail in other chapters and in this Chapter are discussed only briefly