Type I Tyrosinemia: Lack of Immunologically Detectable Fumarylacetoacetase Enzyme Protein in Tissues and Cell Extracts

Abstract

Type I hereditary tyrosinemia is characterized by the almost complete absence of fumarylacetoacetase in tissues and cells from patients. To investigate the -nature of the enzyme deficiency, extracts of tissues (liver and kidney) and cells (lymphocytes and fibroblasts) were immunochemically screened for the presence of fumarylacetoacetase enzyme protein. The antibodies used were raised in rabbits against fumarylacetoacetase purified from beef liver. These antibodies cross-reacted strongly with the human enzyme. No cross-reacting material was found in extracts from liver (n = 4) and kidney (n = 1) from patients. Extracts from lymphocytes and cultured skin fibroblasts from patients were investigated as well. However, no crossreacting material was found in extracts of these cells.