Antibodies pepsin

Chemical cleavage of IgG monoclonal antibody pepsin - Fab2+ Fc... 

Figure 20.10 Digestion of IgG class antibodies with pepsin results in heavy chain cleavage below the disulfide groups in the hinge region. The bivalent fragments that are formed are called F(ab )2. The remaining Fc region normally is severely degraded into smaller peptide fragments.

F(ab )2 fragments of antibodies are generated by pepsin digestion of whole IgG antibodies to remove a portion of the Fc region (see Sect. 1.1). Elimination of nonspecific binding of the Fc region of antibodies to Fc receptors on cell surfaces in... 

An antibody can be cleaved by enzymes such as papain and pepsin into different fragments (Fig. 4.2). 

Since antibodies of different species and different subclasses are variably cleaved by pepsin and papain, a test run is recommended to check incubation time and cleavage conditions. Take samples of different incubation time, freeze rapidly, and monitor the fragmentation by SDS-PAGE at the end of the experiment. Apply the samples both with and without DDT. 

Compared with pepsin predigestion, microwave heating markedly enhanced the staining of aberrant p53 antigen with Pab 1801-D07 antibody cocktail in paraffin or frozen sections in adenocarcinoma of the lung (Resnick et al., 1995). 

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