Antibodies effector sites

Volume 3 is devoted primarily to the antibody aspect of the immune recognition and the immunochemistry of the complement system. The structure of antibodies is discussed and correlated with our present knowledge of antibody effector sites, antigenic features, and combining sites. This is followed by a chapter on the immunochemistry and biology of complement proteins and finally by a review of our current knowledge of the immunochemistry of serum albumin. 

The main site of the mucosal immune system in the gut is referred to as gut-associated lymphoid tissue (GALT), which can be divided into inductive and effector sites. In the small intestine, the inductive sites are in the Peyer s patches, which consist of large lymphoid follicles in the terminal small intestine. The contact with external antibodies triggers a series of cascade events in the body based on immune response (Brandtzaeg et al., 1999). 

Third, they can act as antigens and generate an immune response which may result in a lower effective concentration of the protein at its effector site (because some of it is bound to the antibody) or occasionally in a clinical allergic syndrome - most particularly if the protein has been derived in whole or in part from non-human DNA (mouse DNA is incorporated with human in some production systems and this tends to produce more common immunological... 

Fig. 4 Mucosal immunization and production of IgA antibodies in various mucosal surfaces via the common mucosal-simmu-nization system. Nasal and rectal vaccinations usually result in IgA production in upper respiratory tract and genitourinary tract, respectively, whereas effector sites by oral vaccination are expected to include many mucosal surfaces.

Fig. 1. Intracellular delivery of effector molecules using bispecific antibodies. A bifunctional carrier is constructed by linking a monoclonal anti-effector antibody to a monoclonal cell-targeting antibody. A noncovalent complex forms when the effector is added and binds to its specific antibody-combining sites. The targeting antibody directs this preformed complex to a distinct receptor site on the cell membrane. Alternatively, cells can be pretreated with the bispecific antibody, allowing the empty combining sites of the cell-bound reagent to be filled by subsequently added effector molecules. Surface-localized complexes quickly enter cells via a receptor-mediated endocytosis pathway. Escape of the effector from the cell vesicle system and passage into the cytosol is achieved but occurs slowly ( 24 h).

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