Lgm
IgM.
IgM is the antibody first secreted during primary response
The class of immunoglobulin to respond to the fist exposure of an antigen is immunoglobulin class M (IgM). While Immunoglobulin G (IgG) would predominate on the second exposure.
It first exhibits its particular surface antibody before it ever encounters an antigen.
Direct ELISAs are sometimes refered to as sandwich ELISAs because unlike the indirect ELISA in which the antigen is binded nonspecifically to the ELISA plate, an antibody is first plated that will capture the antigen. Next, an enzyme-linked antibody is plated and lastly a substrate which creates a measurable color change (OD). The two antibodies "sandwich" the antigen.
ELISA means enzyme linked immunosorbent assay. Let us keep it simple and describe a direct ELISA. First; a well plate is coated on the bottom of the well with an antigen epitope of interest. Then an antibody is prepared with an enzyme linked to it. Then the antibody is put into the well with a amount of neutral solution. The well is washed. Then the substrate of the antibody is put into the solution. If the antibody attached to the epitope was not washed away the enzyme will react with its substrate and this reaction will color the solution.
IgM is produced upon initial exposure to an antigen. For example, when a person receives the first tetanus vaccination, antitetanus antibodies of the IgM class are produced 10 to 14 days later. IgM is abundant in the blood.
the secondary immune response is faster and stronger than the first. the primary response also takes a few days to react with the antigen whereas the secondary immune response reacts faster to an antigen.
Primary versus Secondary Immune ResponseThe primary immune response occurs the first time that the immune system comes in contact with the antigen. During this time the immune system has to learn to recognize antigen and how to make antibody against it and eventually gain immunological memory. This primary response takes time (about two weeks) and during this time the person experiences signs of illness. IgM antibodies are the hallmark of a new infection because they are the first antibodies made when a person is exposed to an antigen for the first time. After the body learns to make IgM antibodies, it will start making IgG antibodies to the antigen.The secondary immune response occurs the second time (3rd, 4th, etc.) the person is exposed to the same antigen. At this point immunological memory has been established and the immune system can start making antibodies immediately. The antigen usually is killed within minutes and the person is not aware that he/she was attacked. The antibodies in this response are IgG and IgA or (in the case of allergy IgE).
antigen
lymphocytes make antibodies by first getting the antigen marker from a pathogen. Then, using a 'toolkit' of various protein fragments, they use the marker as a 'blueprint' to make the antibody.
Yes. The first signal that a T cell receives from an antigen presenting cell (dendritic cell) is MHC presenting an antigen (foreign peptide). This gives the T cell specificity to this antigen.