Page 1396 - Veterinary Immunology, 10th Edition

VetBooks.ir Reagents Used in Serological Tests

Serum

The most common source of antibodies is serum obtained from
clotted blood. Serum may be stored frozen and tested when
convenient. If necessary, the serum can be depleted of complement

activity by heating to 56° C for 30 minutes.

Antiglobulins

Immunoglobulins are antigenic when injected into an animal of a
different species. For example, purified dog immunoglobulins can

be injected into rabbits. The rabbits respond by making specific
antibodies called antiglobulins. Depending on the purity of the
injected immunoglobulin, it is possible to make nonspecific
antiglobulins against immunoglobulins of all classes, or very

specific antiglobulins directed against single classes. Antiglobulins
are essential reagents in many immunological tests.

Monoclonal Antibodies

Hybridoma-derived monoclonal antibodies are pure and specific,
can be used as standard chemical reagents, and can be obtained in
almost unlimited amounts (Chapter 15). As a result, monoclonal
antibodies frequently replace conventional antiserum as reagents in

immunodiagnostic tests.

Specific Antibodies

When detecting antigens in tissues or body fluids, the first steps
may involve the use of a specific antibody against the antigen of

interest. Although these antibodies are usually made by
immunizing goats or rabbits, there is a growing interest in using
chicken IgY antibodies. Birds may react very strongly against
mammalian antigens. Chickens produce large amounts of IgY

antibodies that become concentrated in the egg yolk. It may be
much more convenient to harvest large amounts of antibody from

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