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Erythrocyte Metabolism in Purine Nucleoside Phosphorylase Deficiency After Enzyme Replacement Therapy by Infusion of Erythrocytes

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Erythrocyte Metabolism in Purine Nucleoside Phosphorylase Deficiency After Enzyme Replacement Therapy by Infusion of Erythrocytes Erythrocyte metabolism in purine nucleoside phosphorylase deficiency after enzyme replacement therapy by infusion of erythrocytes. G E Staal, … , S K Wadman, D W Martin J Clin Invest. 1980;65(1):103-108. https://doi.org/10.1172/JCI109639. Research Article Purine nucleoside phosphorylase deficiency is associated with a severely defective T-cell immunity. A patient with purine nucleoside phosphorylase deficiency was treated with transfusions of irradiated erythrocytes and plasma. This resulted in a remarkable correction of the metabolic disturbances in the patient. The urinary excretion of inosine, deoxyinosine, guanosine, and deoxyguanosine decreased, whereas uric acid excretion as well as serum uric acid concentration increased. It could be shown that the enzyme activity of the circulating erythrocytes correlated inversely with the urinary excretion of nucleosides and directly with the excretion of uric acid. As a consequence of the therapy, several glycolytic intermediates of the erythrocytes were increased, especially 2,3-diphosphoglycerate. The high 2,3-diphosphoglycerate level caused a shift to the right of the oxygen dissociation curve (P50 = 32.9 mm Hg). The immunological status of the patient showed definite improvement after the enzyme replacement therapy. Find the latest version: https://jci.me/109639/pdf Erythrocyte Metabolism in Purine Nucleoside Phosphorylase Deficiency after Enzyme Replacement Therapy by Infusion of Erythrocytes GERARD E. J. STAAL, JAN W. STOOP, BEN J. M. ZEGERS, Louis H. SIEGENBEEK VAN HEUKELOM, MARGREET J. M. VAN DER VLIST, SIEM K. WADMAN, and DAVID W. MARTIN, Unit of Medical Enzymology, Department of Hematology, State University Hospital, and University Children's Hospital "Het Wilhelmina Kinderziekenhuis," Utrecht, The Netherlands; University of California, School of Medicine, Department of Medicine, San Francisco, California 94101 A B S T R A C T Purine nucleoside phosphorylase de- Deoxyguanosine, one of the substrates of PNP, ac- ficiency is associated with a severely defective T-cell cumulates in the urine of PNP-deficient children (6). immunity. A patient with purine nucleoside phos- dGTP is present in erythrocytes from PNP-deficient phorylase deficiency was treated with transfusions of patients, but not in normal erythrocytes (7). It was sug- irradiated erythrocytes and plasma. This resulted in a gested that dGTP may be toxic for the T cells (7). remarkable correction of the metabolic disturbances in Ullman et al. (8) could demonstrate in T-lymphoma the patient. The urinary excretion of inosine, deoxy- cells, deficient in PNP, that deoxyguanosine is first inosine, guanosine, and deoxyguanosine decreased, phosphorylated by deoxycytidine kinase and accumu- whereas uric acid excretion as well as serum uric acid lated as dGTP. By inhibiting ribonucleotide reductase, concentration increased. It could be shown that the dGTP depletes the cell of dCTP, thus preventing the enzyme activity of the circulating erythrocytes cor- synthesis of DNA. Adenosine deaminase deficiency is related inversely with the urinary excretion of nucleo- associated with severe combined immunodeficiency. sides and directly with the excretion of uric acid. As a In these patients dATP accumulates in the erythrocytes consequence of the therapy, several glycolytic inter- (9). Polmar et al. (10) reported that transfusions of eryth- mediates of the erythrocytes were increased, especially rocytes containing adenosine deaminase may provide a 2,3-diphosphoglycerate. The high 2,3-diphosphogly- way to treat patients with adenosine deaminase de- cerate level caused a shift to the right of the oxygen ficiency. After a few transfusions of erythrocytes, res- dissociation curve (P50 = 32.9 mm Hg). toration of immunological function (10) and diminished The immunological status of the patient showed erythrocyte dATP levels were observed (9). Normal definite improvement after the enzyme replacement human erythrocytes are rich in PNP and we decided therapy. to treat our patient with PNP deficiency with eryth- rocyte transfusions. It is the aim of this paper to report INTRODUCTION the effects of the transfusion of normal erythrocytes on the metabolic state of a patient with a PNP deficiency. Purine nucleoside phosphorylase (EC 2.4.2.1 purine This treatment has led to a gradual and partial res- orthophosphate ribosyltransferase) catalyzes the phos- toration of T-cell immunity that has been described in phorolysis of deoxyinosine and deoxyguanosine. Pa- detail separately (11, 12). tients deficient in purine nucleoside phosphorylase (PNP)l show disturbances in thymus-dependent im- munity and have normal or nearly normal humoral METHODS immunity (1-5). Venous blood was collected with heparin (30 U/ml). Immedi- ately after collection of the blood a part of it was deproteinized for the determination of glycolytic intermediates. Depro- Received for publication 11 December 1978 and in revised teinization and determination of glycolytic intermediates form 18 July 1979. except 2,3-diphosphoglycerate, were performed according to 1 Abbreviation used in this paper: PNP, purine nucleoside the methods of Minakami et al. (13). The 2,3-diphosphogly- phosphorylase. cerate content of the acid extract was determined with a Sigma J. Clin. Invest. (D The American Society for Clinical Investigation, Inc. 0021-9738/80/01/0103/06 $1.00 103 Volume 65 January 1980 103-108 test-kit (Sigma Technical Bulletin 35-UV [12-74]), Sigma and uridine has some demonstrable effect on the percentage Chenmical Col., St. Louis, Mo. of E-rosetting T cells, but not on the lymphocyte count or the Glycolytic enzymes were determined by the methods of in vitro phytohemagglutinin response; also the granulocyte Beutler (14). Substrates, coenzymes, and auxiliary enzymes number and the megaloblastic bone marrow characteristics for determination of glycolytic enzymes, purine enzymes, and remained unchanged (12, 17). intermediates, except for the determination of 2,3-diphos- After 25 November 1976, the patient was treated with ir- phoglycerate, were obtained from C. F. Boehringer and Sons, radiated erythrocyte and plasma transfusions according to Mannheim, West Germany. All other chemicals were of ana- Polmar et al. (10). Before each transfusion -70 ml ofblood was lytical grade of purity. withdrawn to avoid hemosiderosis. Packed erythrocytes (15 PNP activity was determined according to Kalckar (15). A ml/kg body wt) and plasma (20 ml/kg body wt) were given at unit of activity is defined as the amount of enzyme required a general frequency of once a month. Initially, erythrocytes to catalyze the conversion of 1 ,umol inosine to hypoxanthine and plasma were given together, subsequently (from the fifth per minute. The specific activity is expressed as units per transfusion) they were given alternately with an interval of gram Hb. 14 d. The immunological status of the patient showed definite Determination of urinary ribonucleosides and deoxy- improvement after the enzyme replacement therapy. The ribonucleosides was done on aliquots of 24-h urine collections results have been published in detail separately (11, 12), and each time before transfusion. During the entire period of they are summarized below. After the second blood trans- enzyme replacement therapy the patient was on an ad lib. diet; fusion, the number ofperipheral blood lymphocytes increased earlier (16) it was shown that a purine-restricted diet had up to 1,200/mm3. The increase was transient and was observed little or no influence on the total daily excretion of ribonucleo- subsequently after each erythrocyte and plasma transfusion. sides and deoxyribonucleosides. Ribonucleosides and deoxy- After the third transfusion, the percentage of E-rosetting T ribonucleosides were determined with high pressure liquid lymphocytes gradually increased to normal levels; this was chromatography as described in detail earlier (17). Uric acid followed by an increase in the phytohemagglutinin re- was determined enzymatically with uricase. sponsiveness of the lymphocytes and soon thereafter by the Case summary and the effect of treatment with enzyme appearance of immunoglobulin (Ig)M-binding T lymphocytes. replacement on the immunological parameters. R.V., a fe- It could be concluded that partial restoration of cellular im- male child, now 3.5 yr old, is the fourth child of healthy, not munity was gradually attained. During the follow-up period knowingly related parents. Of these parents, the first two of2.5 yr, the various immunological parameters varied widely; children, both females, died early in life as a consequence of however, the extremely depressed starting levels were a selective impairment of T-cell function and an apparently never seen again. Finally, it should be mentioned that during normal B-cell function (18). The third child, a boy, is healthy the enzyme replacement therapy the granulocytopenia disap- and is now 5 yr old. The fourth child developed a selective peared and the megaloblastic bone marrow became normal. impairment of T-cell function during the 1st yr of life, whereas B-cell function apparently developed quite normally (5). The immunodeficiency in the fourth child was associated with a RESULTS AND DISCUSSION PNP deficiency as could be concluded from the absence of enzyme activity in erythrocytes, lymphocytes, and fibroblasts Before enzyme replacement, no PNP activity could be of the patient (4, 5) as well as from the excretion pattern of detected in the erythrocytes of the patient (3). Fig. 1 purine metabolites: high urine
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