Altered purine and pyrimidine metabolism in erythrocytes with purine nucleoside phosphorylase deficiency

✍ Scribed by Irving H. Fox; Jan Kaminska; N. Lawrence Edwards; Erwin Gelfand; Kenneth C. Rich; William N. Arnold

• Publisher: Springer
• Year: 1980
• Tongue: English
• Weight: 771 KB
• Volume: 18
• Category: Article
• ISSN: 0006-2928
• DOI: 10.1007/bf00484238

✦ Synopsis

Purine and pyrimidine metabolism was compared in erythrocytes from three patients from two families with purine nucleoside phosphorylase deficiency and T-cell immunodeficiency, one heterozygote subject for this enzyme deficiency, one patient with a complete deficiency of hypoxanthine-guanine phosphoribosyltransferase, and two normal subjects. The erythrocytes from the heterozygote subject were indistinguishable from the normal erythrocytes. The purine nucleoside phosphorylase deficient erythrocytes had a block in the conversion of inosine to hypoxanthine. The erythrocytes with 0.07% of normal purine nucleoside phosphorylase activity resembled erythrocytes with hypoxanthine-guanine phosphoribosyltransferase deficiency by having an elevated intracellular concentration of PP-ribose-P, increased synthesis of PP-ribose-P, and an elevated rate of carbon dioxide release from orotic acid during its conversion to UMP. Two hypotheses to account for the associated immunodeficiency--that the enzyme deficiency leads to a block of PP-ribose-P synthesis or inhibition of pyrimidine synthesis--could not be supported by observations in erythrocytes from both enzyme-deficient families.