Page 888 - Veterinary Immunology, 10th Edition

VetBooks.ir Adaptive Immunity

Antibody-Mediated Immunity

Virus proteins are antigenic, and it is against these that antiviral
antibody responses are largely mounted (Fig. 27.6). Antibodies can
prevent cell invasion by blocking the adsorption of virions to target

cells, by stimulating virus phagocytosis, by triggering complement-
mediated virolysis, or by causing viral clumping and thus reducing
the number of infectious units available for cell invasion. Binding of
antibodies alone does not destroy viruses since the splitting of
virus-antibody complexes releases infectious virions.

FIG. 27.6 The ways in which the immune system can protect the
body against viruses.

Antibodies are not only directed against virion proteins but are

also against viral proteins expressed by infected cells. As a result,
these infected cells are also destroyed. Antibody-mediated
destruction of virus-infected cells occurs in Newcastle disease,

rabies, bovine virus diarrhea, infectious bronchitis of birds, and

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