Page 435 - Veterinary Immunology, 10th Edition

thus the specificity of antigen binding. Since the shape of the
VetBooks.ir antibody-binding site is complementary to the conformation of the

antigenic determinant, the hypervariable sequences are also called
complementarity determining regions (CDRs). Each V-domain is

folded in such a way that its three CDRs come into close contact
with the antigen (Fig. 15.4).

FIG. 15.3 The variable regions of the light and heavy chains of an
immunoglobulin molecule are divided into three highly variable
complementarity-determining regions separated by relatively
constant framework regions.

FIG. 15.4 The way in which the complementarity-determining
regions are folded to form the antigen binding site on an
immunoglobulin molecule. A similar folding occurs in the peptide
chains of the TCR.

Constant Regions

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