Antibodies Fc region

Carlisle, M.S., McGregor, D.D. and Appleton, J.A. (1991b) The role of the antibody Fc region in rapid expulsion of Trichinella spiralis in suckling rats. Immunology 74, 552-558. 

Antibodies that, by binding to the cell surface antigen, mark the tumour cell for destruction. NK cells and macrophages express cell surface receptors that bind to the antibody Fc region (Box 13.2). Thus, antibody bound to tumour antigens directs these immune elements directly to tumour surface. Antibodies also activate complement, which is capable of directly lysing tumour cells. 

Figure 13.4 Binding of appropriate antibody to tumour-associated antigens marks the tumour cell for destruction. This is largely due to the presence of a domain on the antibody Fc region (see also Box 13.2), which is recognized and bound by macrophages and NK cells. Therefore, congregation of such cells on the surface of the tumour is encouraged. This greatly facilitates their cytocidal activity towards the transformed cells...

In allergic subjects, IgE antibodies, as well as being free in serum, are fixed to the exfiacellular D1 distil and D2 proximal domains of the FceRl receptor on mast cells and basophils via the Ce2 and Ce3 domains of the antibody Fc region. 

Fc,RI High affinity receptor for IgE Fc,RII Low affinity receptor for IgE FcR Receptor for Fc region of antibody... 

Rheumatoid factors Antibodies reactive with the Fc region of immunoglobulin G. 

Figure 1.22 The solvent accessibility of lysine residues in the Fc region of an antibody is illustrated by highlighting the lysine groups in solid gray. Some lysine e-amine groups are extremely accessible to conjugation, while others are only partially exposed, making them difficult to modify in bioconjugation reactions.

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.

Figure 20.11 Papain digestion of IgG antibodies primarily results in cleavage in the hinge region above the interchain disulfides. This produces two heavy-light chain pairs, called Fab fragments, each containing one antigen binding site. The Fc region normally can be recovered intact.

Figure 20.15 An affinity chromatography support containing iminodiacetic acid groups chelated with nickel may be used to remove excess enzyme after reactions to produce antibody-enzyme conjugates. The nickel chelate binds to the antibody in the Fc region, retaining the conjugate while allowing free enzyme to pass through the gel unretarded.

Figure 24.2 Antigens may be detected in cells or tissue sections through the use of protein A-coated gold particles. The binding of a specific primary antibody to its target antigen can be localized by the immunoglobulin binding capability of protein A, which occurs in the Fc region of the antibody.

Jagannath, C., and Sehgal, S. (1989) Enhancement of the antigen-binding capacity of incomplete IgG antibodies to Brucella melitensis through Fc region interactions with Staphylococcal protein A. J. Immunol. Meth. 124, 251-257. 

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