Page 177 - Veterinary Immunology, 10th Edition

antibody complexes from the blood; and the protein is rapidly
VetBooks.ir eliminated (Fig. 6.13).

FIG. 6.13 The clearance of a soluble antigen from the
bloodstream. Note the three phases of this clearance.

This triphasic clearance pattern of redistribution, catabolism, and
immune elimination may change according to circumstances. For

example, if the animal has not been previously exposed to a protein
antigen, it takes between 5 and 10 days before immune elimination
occurs. If, on the other hand, the animal has been primed by prior
exposure to the protein, a secondary immune response will occur in

2 to 3 days, and the catabolic phase will be short. If antibodies are
present at the time of antigen administration, immune elimination
is immediate, and no catabolic phase is seen. If the injected material
is not antigenic, or if an immune response does not occur,

catabolism will continue until all the material is eliminated.

Fate of Material Administered by Other

Routes

When foreign material is injected into a tissue, some local damage

and inflammation are bound to occur, and DAMPs are released. As
a result, neutrophils and macrophages migrate toward the injection
site and phagocytose the injected material. Some will also be

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