OBJECTIVES: The activity of membrane-bound ecto-5'-nucleotidase and soluble e-Ns and c-N-II 5'-nucleotidases was evaluated on lymphocytes from patients affected by B-cell chronic lymphocytic leukemia (B-CLL). A statistically significative decrease in ecto-5'-nucleotidase, e-Ns, and c-N-II activities was observed in peripheral blood lymphocytes and in B and T populations from affected individuals. DESIGN AND METHODS: For the assay of ecto-5'-nucleotidase, e-Ns, and c-N-II activity we used a radioactive procedure coupled to HPLC. Since the ecto-5'-nucleotidase is identified as CD73 antigen, we performed immunofluorescence analysis using a specific monoclonal antibody. We analyzed ecto-5'-nucleotidase mRNA by RT-PCR to ascertain the possibility of an alteration in the transcription of its gene. RESULTS: A decrease in ecto-5'-nucleotidase activity was correlated to reduction in ecto-5'-nucleotidase positive cells (CD73+) in leukemia patients. RT-PCR produced a fragment of the expected size and the specific mRNA was found expressed in both healthy subjects and leukemia patients. CONCLUSIONS: The decrease in ecto-5'-nucleotidase activity in patients with B-CLL is not due to loss of transcription of the specific mRNA. The presence of point mutations, splicing alteration, or posttranslational modifications must be investigated. If a defect at DNA or RNA level will be detected, the molecular analysis will be considered for diagnosis of B-cell chronic lymphocytic leukemia.
OBJECTIVES: The activity of membrane-bound ecto-5'-nucleotidase and soluble e-Ns and c-N-II 5'-nucleotidases was evaluated on lymphocytes from patients affected by B-cell chronic lymphocytic leukemia (B-CLL). A statistically significative decrease in ecto-5'-nucleotidase, e-Ns, and c-N-II activities was observed in peripheral blood lymphocytes and in B and T populations from affected individuals. DESIGN AND METHODS: For the assay of ecto-5'-nucleotidase, e-Ns, and c-N-II activity we used a radioactive procedure coupled to HPLC. Since the ecto-5'-nucleotidase is identified as CD73 antigen, we performed immunofluorescence analysis using a specific monoclonal antibody. We analyzed ecto-5'-nucleotidase mRNA by RT-PCR to ascertain the possibility of an alteration in the transcription of its gene. RESULTS: A decrease in ecto-5'-nucleotidase activity was correlated to reduction in ecto-5'-nucleotidase positive cells (CD73+) in leukemiapatients. RT-PCR produced a fragment of the expected size and the specific mRNA was found expressed in both healthy subjects and leukemiapatients. CONCLUSIONS: The decrease in ecto-5'-nucleotidase activity in patients with B-CLL is not due to loss of transcription of the specific mRNA. The presence of point mutations, splicing alteration, or posttranslational modifications must be investigated. If a defect at DNA or RNA level will be detected, the molecular analysis will be considered for diagnosis of B-cell chronic lymphocytic leukemia.
Authors: Dianne Pulte; Richard R Furman; M Johan Broekman; Joan H F Drosopoulos; Harold S Ballard; Kim E Olson; Jorge R Kizer; Aaron J Marcus Journal: Clin Lymphoma Myeloma Leuk Date: 2011-08
Authors: Sara Serra; Alberto L Horenstein; Tiziana Vaisitti; Davide Brusa; Davide Rossi; Luca Laurenti; Giovanni D'Arena; Marta Coscia; Claudio Tripodo; Giorgio Inghirami; Simon C Robson; Gianluca Gaidano; Fabio Malavasi; Silvia Deaglio Journal: Blood Date: 2011-10-13 Impact factor: 22.113