Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.4.17 (adenosine deaminase)
 5,206 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have established long term cell lines from a patient with adenosine deaminase (ADA)-deficient severe combined immunodeficiency by stimulation of blood and bone marrow cells with PHA and IL-2 followed by transformation of the activated cells with the human retrovirus HTLV-I. Despite the absence of detectable T cells in the patients blood, cell lines grew that carried the phenotype of mature activated T cells. TJF-2, the line established from blood, was characterized in detail. The concentration of ADA in TJF-2 cells was less than 1% of normal (3.2 U vs 413.0 U). Studies with pharmacologic inhibitors of ADA suggest that the residual adenosine deaminating activity of TJF-2 is from an enzyme distinct from true ADA, a nonspecific aminohydrolyase. Growth of TJF-2 cells was hypersensitive to inhibition by 2'-deoxyadenosine compared to normal T cells (ID50, 55 microM vs greater than 1000 microM). Analysis of 2'-deoxyadenosine-challenged cells showed that TJF-2 cells accumulated significant levels of deoxyadenosine triphosphate, whereas normal T cells did not unless they were also incubated with the ADA inhibitor deoxycoformycin. Southern and Northern blot analysis of these cells revealed a grossly intact ADA gene that produced a normal size ADA mRNA. Yet, despite ADA deficiency, cells of the TJF-2 line were otherwise indistinguishable from HTLV-I-transformed T cells derived from normal donors with respect to dependence on exogenous IL-2 for growth, clonal rearrangement patterns of TCR beta-chain genes, response to PHA, and rapid restoration of cellular volume after hypotonic challenge. The TJF-2 line thus represents a unique HTLV-I-transformed human T cell line exhibiting ADA deficiency and its expected metabolic consequences.
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PMID:Establishment and characterization of adenosine deaminase-deficient human T cell lines. 249 84

ATL is a unique T-cell malignancy first described by Takatsuki and colleagues in 1970s. We estimate that more than 300 patients a year have been detected in the endemic areas of Kyushu, Japan. The surface phenotype of ATL cells characterized by monoclonal antibodies is T3+, T4+, T8-, T11+ and Tac+. In all cases the serum is positive for anti-HTLV-I antibodies and the ATL cells contain the proviral DNA of HTLV-I. Variations in the clinical features of atypical ATL suggested a division of the spectrum of ATL into five types: acute; chronic; smoldering; crisis; and lymphoma. Typical ATL takes an acute course. The survival time is short, with 50% mortality within approximately 5 months. In general a poor prognosis is indicated by the elevation of serum lactate dehydrogenase, calcium, and bilirubin, as well as by high WBC. Smoldering ATL is characterized by the presence of a few abnormal cells (0.5%-3%) in the peripheral blood over a long period. Crisis in chronic or smoldering ATL means the progression of the disease to acute ATL. The lymphoma type of ATL is considered to be a form of T-cell-type non-Hodgkin's lymphoma in which malignant cells contain proviral DNA of HTLV-I. Screening of the sera from healthy adults for presence of the anti-HTLV-I antibodies revealed that 3.6% of healthy individuals in Kumamoto Prefecture, which is located in the middle of Kyushu, were HTLV-I carriers. Family studies showed that the routes of natural infection of HTLV-I are from mother to child and also from husband to wife. The borderline between the healthy carrier state and smoldering ATL remains unclear. Smoldering ATL is frequently diagnosed in patients with fungus infection of the skin, chronic lymphadenopathy, interstitial pneumonitis, chronic renal failure and strongyloidiasis. Five patients with ATL refractory to conventional chemotherapeutic agents were treated with 2'-deoxy-coformycin (DCF), a potent inhibitor of adenosine deaminase. Two patients showed a good response, and three were resistant to DCF. In addition our experiences with a concurrence of lymphoma-type ATL in three sisters and spontaneous remissions in a patients with chronic ATL will be referred.
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PMID:[Overview of ATL (adult T-cell leukemia) research]. 288 29