The primary immune response

What triggers is your immune response? What are considered the primary immune system cells? What is responsible for secondary immune response? What Is the Primary Immune Response ? To protect you from bacteria, viruses, and other foreign substances (known as antigens), the immune system needs to recognize these substances and develop a response.

Upon initial exposure to an antigen, a primary response occurs.

Any response of the immune system to an antigen including antibody production or cell-mediated immunity. Secondary Immune Response is the reaction of the immune system when it contacts an antigen for the second and subsequent times. When foreign antigen is first introduced in the body, a primary antibody response occurs. It occurs following the first exposure to a foreign antigen. At the beginning of the primary immune response, there are no previously produced antibodies.

IgM is produced first followed by IgG. If the response is against a viral infection , IgA is also produced. When the primary response ends, IgG predominates over the other two.

During this time the immune system has to learn to recognize antigen and how to make antibody against it and eventually gain immunological memory. Innate immune responses are those that rely on cells that require no additional “training” to do their jobs. These cells include neutrophils , monocytes , natural killer (NK) cells and a set of proteins termed the complement proteins.

The secondary immune response occurs when the second time (3r 4th, etc.) the person is exposed to the same antigen. This immune reaction usually does not induce immune memory. The types of support offered are comparable to what is used for primary immune deficiencies.

The primary immunodeficiency diseases are a group of disorders caused by basic defects in immune function that are intrinsic to, or inherent in, the cells and proteins of the immune system. There are more than 4primary immunodeficiencies. A response of the body to a foreign substance, called an antigen, especially a microorganism or virus that causes disease.

The immune response involves the action of white blood cells called lymphocytes, which work to deactivate foreign antigens, often by stimulating the production of antibodies. Immune Response Following the first exposure to a foreign antigen, a lag phase occurs in which no antibody is produce but activated B cells are differentiating into plasma cells. The lag phase can be as short as 2-days, but often is longer, sometimes as long as weeks or months. The primary immune responses can be divisible into four phases (lag phase, exponential phase, steady state phase, and declining phase) (Fig. ). The lag (latent) phase is the period from the initial exposure of immunogen to the time of detection of antibodies (In humans the average time of lag phase is about one week).

Central to the immune system’s ability to mobilize a response to an invading pathogen, toxin or allergen is its ability to distinguish self from non-self. The host uses both innate and adaptive mechanisms to detect and eliminate pathogenic microbes. Both of these mechanisms include self-nonself discrimination.

The two different types of phagocyte are neutrophils and macrophages. Macrophages are relatively large cells and travel in the blood as monocytes. Definition: Primary Immune Response is the reaction of the immune system when it contacts an antigen for the first time. Appearance: Appears mainly in the lymph nodes and spleen. The plasma cells form the basis of primary immune response , which is the response mounted by the immune system to an antigen that the animal encounters for the first time.

The primary response has a characteristic lag phase, during which naive B-cells proliferate and differentiate into plasma cells and memory cells. Our bodies are covered by the skin and this is the first primary defence that we have. Because of the generation of memory cells, the secondary immune response is faster and stronger, leading to more effective pathogen elimination in comparison to the primary immune response.

The only thing I will add to these excellent , alluded to by SG, is that the primary immune response corresponds to activating naive cells, while the secondary response corresponds to activating memory cells. A primary response occurs faster than a secondary response.