Page 495 - Veterinary Immunology, 10th Edition

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FIG. 16.13 The mechanism of class switching. In this example, a
switch is made from IgM production to IgA production by deleting
intervening heavy chain genes and joining the V genes to the
appropriate heavy chain gene.

B Cell Antigen Receptors and Soluble

Immunoglobulins

Immunoglobulins are first produced as cell-bound BCRs and are
subsequently secreted as antibodies. The heavy chains of BCRs
have a hydrophobic transmembrane C-terminal domain that

attaches them to a B cell surface. This domain is absent from the
secreted antibody. The switch between the two forms results from
the differential splicing of exons. For example, the IGHM gene

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