Antigens artificial

Isoagglutinins are proteins which have an antibody-like specificity against foreign blood corpuscles, but which are present normally without the need to introduce an antigen artificially. Along with the blood-type substances of blood corpuscles, these isoagglutinins are responsible for the incompatibility in some blood transfusions (see Chapt. XVII-7). 

This is produced as a result of an antigenic stimulus. This stimulus may occur naturally by means of a clinical or subclinical infection, or artificially by the deliberate introduction into the body ofthe appropriate antigen in the form ofa vaccine or toxoid (Chapter 16). This type of immunity is normally long-lasting. 

Vaccination of lambs with a contortin-enriched preparation gave a mean reduction in worm burdens of 78% (Table 13.1) (Munn et al., 1987). This result was particularly significant because it showed that proteins expressed on the surface of the gut, albeit from a blood-feeding nematode, could induce high levels of protective immunity when used as an immunogen. These proteins are not normally accessible to the host immune system during the course of infection they are termed hidden or concealed antigens and the immunity conferred by them is described as artificial immunity. 

Brandtzaeg P. Evaluation of immuofluorescence with artificial sections of selected antigenicity. Immunology 1972 22 177-183. 

An interesting practical application of these factors has been initiated by Morgan,127- 128 who prepared an artificial antigen with Group A specificity by combining the Blood Group A factor from hog mucin with a... 

VII. Artificial Antigens from Blood Group Substances. 53... 

Normal immunoglobulins (often termed immune globulins in the USA) represent antibody preparations purified from the plasma, serum or placentas of normal, healthy donors. Blood obtained from such individuals will contain a wide range of antibody specificities. The range of specificities were produced over many years, as the individual s immune system came into contact with various antigens, either naturally (infections) or artificially (by vaccination). 

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