Immunodeficiency disease in animals.

Significant contributions to understanding the role of lymphocyte subpopulations in the immune response and to the characterization of immunodeficiencies in children have been achieved through study of animal models of immunodeficiency. Additional contributions can be made in two important areas. One is through identification of relevant, naturally-occurring models of adenosine deaminase deficiency and purine nucleoside phosphorylase deficiency. The second, and potentially more important contribution, would be the identification of the metabolic basis for existing immune deficiencies. The necessary collaborative working arrangements should be established to achieve this objective. Demonstration of the metabolic basis for immune deficiencies in animals may enable the identification of similar defects in people, and eventually lead to enzyme or metabolite delivery schemes for treatment of affected children.