Antigen Antiserum

Serum which contains antibodies. Antisera used in diagnostic tests are obtained from animals injected with the appropriate antigen. Antiserum reacting against several antigens is termed polyvalent. If it reacts against only one antigen it is termed monovalent (or monospecific)... 

XII or XX) removed the capacities of each antiserum to react with all of the antigens, and absorption with each kind of bacteria removed the capacity of all the antisera to react with antigens of that kind of bacteria. 

Antiserum A serum containing an antibody or antibodies produced from animals or humans that have survived exposure to an antigen. 

Antiserum (plural antisera) Blood serum containing one or more polyclonal antibodies that are specific for one or more antigens. The antibodies in an antiserum result from previous immunization or exposure to an agent of disease. 

Sensitivity defines the degree to which an assay can distinguish one compound from another of the same nature and an immunoassay is a function of the particular antibody molecules contained in the antiserum. Specificity of the antiserum is a function of the particular antigen used to immunize the animal. Affinity usually measures how strongly bound is the antigen to the antibody. Titer refers to the concentration level of, in the context of the usage, antibody contained in the obtained serum. 

Mix a fixed volume (fixed concentration ) of antiserum containing the specific antibody with a constant amount of radiolabelled antigen,... 

Where more than one antibody in an antiserum can combine simultaneously with an antigen, the sum of the binding strength is defined as the avidity of the antiserum. 

A polyclonal antiserum contains a heterogeneous mix of antibodies directed against an antigen. 

Antiserums produced in this manner are known as polyclonal because they contain many antibodies produced by different lymphocytes, each one responding either to different antigenic determinants of the original antigen or to other immunogenic substances in the injected material. Such a range of antibodies reduces the specificity of the method. 

Specificity is the ability of an antiserum to recognize only the antigen for which it was generated. 

From each curve the dilution of antiserum which gives 50% binding of that amount of labelled antigen can be determined. ... 

The discovery of Lp(a) by Berg in 1962 (B6) relied on the production of rabbit antisera against beta-lipoprotein and on the selective absorption of these antisera with individual human sera. When certain human sera were used for absorption, the antisera retained precipitation capacity in radial immunodiffusion with 30-35% of individual human sera, which obviously contained a previous unknown antigen. The particle carrying the new antigen shared antigenic properties with beta-lipoprotein, but had an additional antigenic structure. This was evidenced from the only partial fusion of the precipitin bands formed between a positive human serum, the antibeta lipoprotein antiserum and the new absorbed antiserum. 

Figure 4. Double diffusion of extracts from cotton plant tissues and extract from flax against rabbit antiserum to cotton dust. Key. a AD,antisera to dust gin, gin trash If, leaf antigen stm, stem antigen cd, cotton dust antigen bet, bract antigen burr, burr antigen, b NS, normal rabbit serum, c fix, flax extract f-4, cotton dust antigen. Conditions described in Material and Methods.

Figure 5. Double diffusion of cotton dust and house dust extracts against rabbit antiserum to dust (AD). Key f-3, cotton dust antigen hd, house dust extract. Conditions described in Materials and Methods.

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