Adenosine deaminase activity in leukemia patients

The activities of adenosine deaminase (ADA) were measured in the blood plasma, erythrocytes, and lymphocytes of healthy reference persons and in patients affected with leukaemia. ADA is increased in patients with acute immature cell leukaemia, in patients with chronic lymphatic leukaemia it is comparatively low in lymphocytes. In chronic myeloic leukaemia ADA activities are different depending on the activity of the disease. ADA-activities in the blood plasma, erythrocytes, and lymphocytes do not correlate with each other. ADA-activities in leukaemias may be regarded as an indicator of increased purin metabolism rather a as parameter of disturbed cellular immunofunction.     

Adenosine deaminase in ischemia reperfusion injury in patients with myocardial infarction

A comparative study on the levels of erythrocyte adenosine deaminase and lipid peroxidation has been undertaken in patients with myocardial infarction before and after thrombolysis along with matched healthy individuals. Our findings show that adenosine deaminase activity is highly elevated in post-reperfused patients when compared to pre- thrombolysed and healthy persons. Malondialdehyde(MDA) levels are also significantly increased in post-thrombolysed patients. The study reveals an important role of adenosine deaminase in reperfusion injury in patients with myocardial infarction.     

Adenosine deaminase in ischemia reperfusion injury in patients with myocardial infarction

A comparative study on the levels of erythrocyte adenosine deaminase and lipid peroxidation has been undertaken in patients with myocardial infarction before and after thrombolysis along with matched healthy individuals. Our findings show that adenosine deaminase activity is highly elevated in post-reperfused patients when compared to pre- thrombolysed and healthy persons. Malondialdehyde(MDA) levels are also significantly increased in post-thrombolysed patients. The study reveals an important role of adenosine deaminase in reperfusion injury in patients with myocardial infarction.     

Adenosine deaminase polymorphism in sardinia

Summary Red blood cell adenosine deaminase and G-6-PD polymorphisms have been studied in the populations of 17 Sardinian villages located at various altitudes. A total of 1615 individuals of both sexes, with age between 7 and 14 years were examined.The negative relationship between Gd^Med gene frequency and altitude was confirmed.Adenosine deaminase polymorphism showed a considerable variability among the villages examined: ADA² frequency ranged from 0.025 to 0.106. The ADA² frequency was negatively related (p< 0.05) with Gd^Med gene frequency.

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Zusammenfassung Die Erythrocyten-Adenosin-Desaminase und Glucose-6-Phosphat-Dehydrogenase-Polymorphismen sind in Stichproben aus der Bevölkerung von 17 Dörfern auf Sardinien untersucht worden. Diese sind in verschiedener Höhe über dem Meer im zentralen Teil der Insel gelegen.Die negative Häufigkeitsbeziehung zwischen der Genfrequenz Gd^Med und der Höhenlage der Dörfer konnte bestätigt werden.Der Adenosin-Desaminase-Polymorphismus zeigt eine beträchtliche Variabilität zwischen den verschiedenen Dorfpopulationen. Die ADA²-Frequenz liegt zwischen 0,025 und 0,106. Die ADA²-Frequenz steht in negativer Beziehung (p< 0,05) zur Gd^Med-Frequenz.

     

Purine metabolic enzymes in lymphocytes. I. Adenosine deaminase and purine nucleoside phosphorylase activities in mouse lymphocyte subpopulations

The distribution of adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities in lymphoid organs and lymphocyte subpopulations in mice, and the effect of phytohemagglutinin P (PHA-P) and concanavalin A (Con A) on the enzyme activities were studied. ADA activity was distributed equally in cells from all organs used and no mouse strain differences were observed. In contrast, PNP activity varied with the mouse strain, being highest in C57BL/6 mice and lowest in BALB/c mice, and with the organ in ICR mice, being high in peripheral blood lymphocytes and spleen lymphocytes, low in mesenteric lymph node cells and absent or very weak in thymus cells. T and B lymphocytes were prepared from spleen of ICR mice. High ADA activity was found in both T and B lymphocytes, whereas PNP activity in the T lymphocytes was about one-third of that in the B lymphocytes. PNP activity in thymus cells was increased to the normal level of T lymphocytes in the spleens by cultivation without stimulant. The development of PNP activity in thymus cells was partially inhibited by Con A but was not affected by PHA-P. ADA activity in thymus cells was enhanced by in vitro stimulation with PHA-P but not with Con A. In contrast, in spleen lymphocytes the development of ADA activity was enhanced by stimulation with PHA-P and Con A, and that of PNP activity was enhanced by PHA-P but not by Con A.     

Purine metabolic enzymes in lymphocytes. II. Adenosine deaminase and purine nucleoside phosphorylase activities in the immune response

ICR mice were immunized with sheep red blood cells (sRBC). Both adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities in spleen lymphocytes increased faster than the serum antibody titer and reached a peak one week after the immunization. ADA activity increased significantly in T lymphocytes but not in B lymphocytes collected from the spleens of the immunized mice. A statistically significant increase in PNP activity was found in both T and B lymphocytes from the spleens of the immunized mice. Spleen lymphocytes collected from ICR mice which had been immunized with mitomycin C-treated sarcoma 180 (S180) cells one week earlier showed cytotoxic activity against viable S180 cells. Both ADA and PNP activities in spleen lymphocytes of S180-immunized mice increased significantly, and both activities increased in T lymphocytes prepared from spleen of immunized mice. In contrast, an increase was found in PNP activity but not in ADA activity in B lymphocytes. These results suggest that an increase in both ADA and PNP activities may by necessary for the T-cell response in both humoral and cellular immune responses, and that an increase in PNP activity may be necessary for the B-cell response.     

Adenosine deaminase deficiency and severe combined immunodeficiency disease.

The nature of the association of adenosine deaminase deficiency and severe combined immunodeficiency disease is reviewed. The basis for the molecular heterogeneity exhibited by adenosine deaminase in human tissue and the mechanisms whereby a deficiency of this activity results in the extreme perturbation of the immune system as observed in severe combined immunodeficiency are critically discussed.     

Adenosine deaminase from Azotobacter vinelandii. Purification and properties

Adenosine deaminase (EC 3.5.4.4) was found to occur in the extract of Azotobacter vinelandii, strain 0, and purified by heating at 65°C, fractionation with ammonium sulfate, DEAE-cellulose chromatography and gel filtration on Sephadex G-150. Purified adenosine deaminase was effectively stabilized by the addition of ethylene glycol. The molecular weight of the enzyme was estimated to be 66,000 by gel filtration on Sephadex G-150. The enzyme specifically attacked adenosine and 2-deoxyadenosine to the same extent, and formycin A to a lesser extent. The pH optimum of the enzyme was observed at pH 7.2. Double reciprocal plot of initial velocity versus adenosine concentration was concave upward, and Hill interaction coefficient was calculated to be 1.5, suggesting the allosteric binding of the substrate. ATP inhibited adenosine deaminase in an allosteric manner, whereas other nucleotides were without effect. The physiological significance of the enzyme was discussed in relation to salvage pathway of purine nucleotides.     

Detection of Epstein-Barr viral antibodies in patients with acute viral hepatitis

Serum samples obtained from 44 patients with virus A hepatitis, 23 patients with virus B hepatitis, 65 patients with virus non A, non B hepatitis and 100 healthy adults were studied for the presence of Epstein-Barr (EB) virus in the indirect immunofluorescence test. In this work lymphoblastoid cell lines PH3-J-1 and CN37 were used. Among patients with different forms of hepatitis, the statistically significant elevation of the titers of antibodies to EB virus was detected only in the group of patients with virus non A, non B hepatitis, and in 6 cases the etiological role of EB virus was confirmed by serological and hematological methods.