Much of the increased IgG in Aleutian disease of mink is viral antibody.

Aleutian disease (AD) is caused by a persistent infection of mink with an autonomous parvovirus. Chronically infected mink develop widespread plasmacytosis, a marked elevation of their serum IgG, and immune complex disease. A substantial fraction of the IgG in the serum of mink with Aleutian disease may be specifically absorbed by monolayer cell cultures infected with Aleutian disease virus. The maximum percentage of absorption of IgG found was 81% in a mink with 5.4 g/dl of IgG. Mink with the monoclonal gammopathy of Aleutian disease had a particularly large percentage of the IgG absorbed. The percentage of IgG absorbed from serums of mink with Aleutian disease is directly proportional to the serum IgG level and to the Aleutian disease viral antibody titer. The amount of IgG which can be absorbed by infected cell monolayers increases during the course of experimental infection, and the absorption is immunologically specific. Thus, it appears that much of the hypergammaglobulinemia in mink with Aleutian disease represents virus-specific antibody.