Page 544 - Veterinary Immunology, 10th Edition

polymerases, AID, TdT, and repair enzymes is turned on by
VetBooks.ir activating histone modifications and DNA hypomethylation,

triggered by exposure to antigen and the presence of appropriate
cytokines. These epigenetic pathways regulate immunoglobulin

somatic hypermutation, class switch DNA recombination as well as
the differentiation of B cells into plasma cells, and long-lived
memory B cells. Histone modifications affect the class switch and
possibly somatic hypermutation. DNA methylation and miRNAs

influence the activities of cytidine deaminase as well as plasma cell
differentiation. These epigenetic pathways influence the normal
immune response and, if dysregulated, also influence the
development of abnormal B cell responses and autoimmunity.

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