title: Purine nucleoside metabolism in the erythrocytes of patients with adenosine deaminase deficiency and severe combined immunodeficiency.
abstract: Deficiency of erythrocytic and lymphocytic adenosine deaminase (ADA) occurs in some patients with severe combined immunodeficiency disease (SCID). SCID with ADA deficiency is inherited as an autosomal recessive trait. ADA is markedly reduced or undetectable in affected patients (homozygotes), and approximately one-half normal levels are found in individuals heterozygous for ADA deficiency. The metabolism of purine nucleosides was studied in erythrocytes from normal individuals, four ADA-deficiency patients, and two heterozygous individuals. ADA deficiency in intake erythrocytes was confirmed by a very sensitive ammonia-liberation technique. Erythrocytic ADA activity in three heterozygous individuals (0.07,0.08, and 0.14 mumolar units/ml of packed cells) was between that of the four normal controls (0.20-0.37 mumol/ml) and the ADA-deficient patients (no activity). In vitro, adenosine was incorporated principally into IMP in the heterozygous and normal individuals but into the adenosine nucleotides in the ADa-deficient patients. Coformycin (3-beta-D-ribofuranosyl-6,7,8-trihydroimidazo[4,5-4] [1,3] diazepin-8 (R)-ol), a potent inhibitor of ADA, made possible incorporation of adenosine nucleotides in the ADA-deficient patients...
mesh_terms: D000243:Adenosine Deaminase / Q000097:blood / Q000172:deficiency*; D058892:Adenosine Deaminase Inhibitors; D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D001381:Azepines / Q000494:pharmacology; D002675:Child, Preschool; D004912:Erythrocytes / Q000201:enzymology / Q000378:metabolism*; D005260:Female; D005573:Formycins / Q000378:metabolism; D006019:Glycolysis; D006151:Guanosine / Q000378:metabolism; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000097:blood*; D007223:Infant; D007291:Inosine Monophosphate / Q000378:metabolism; D007292:Inosine Nucleotides / Q000378:metabolism; D008297:Male; D009700:Nucleoside Deaminases / Q000172:deficiency*; D011684:Purine Nucleosides / Q000037:antagonists & inhibitors / Q000378:metabolism*; D012263:Ribonucleosides / Q000494:pharmacology; D013866:Thioguanine
chemical_list: D058892:Adenosine Deaminase Inhibitors; D001381:Azepines; D005573:Formycins; D007292:Inosine Nucleotides; D011684:Purine Nucleosides; D012263:Ribonucleosides; D006151:Guanosine; D007291:Inosine Monophosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D009700:Nucleoside Deaminases; D000243:Adenosine Deaminase; D013866:Thioguanine