Histopathological and immunohistological analyses in IgA deficient lymphoplasia (aly/aly) mouse.

The aly/aly mouse has a severe immunodeficiency, because it lacks peripheral lymph nodes as well as IgA and IgG immunoglobulin synthesis. In the present study, we performed histopathological and immunohistological examinations to clarify histological disorders of various immune organs in these mice. Carbon CH40 injections into the apex of the tongue confirmed the absence of submandibular lymph nodes in aly/aly mice. The thymus had a poorly constructed cortex and medulla, and the number of lymphoid follicles was clearly decreased in the spleen. No IgG- or IgA- producing cells were found in any immune organs, including the mucosal immune sites, though several IgM -producing cells were identified. Other characteristic findings included perivascular lymphocytes accumulation in the salivary glands, lungs, liver and pancreas, which caused tissues damage. These results demonstrated that the various lymphoid tissues disorders and organ-specific lymphocyte infiltration cause immuno-deficiency in the aly/aly mouse.