Qualitative and quantitative differences between Burkitt lymphoma and lymphoblastoid cell lines in the expression of membrane ecto‐nucleotidases and in the response to agonists of the A₂‐type adenosine receptor

Abstract

The activity of ecto-nucleotidases has been determined on intact cells from Burkitt lymphoma (BL) and lymphoblastoid cell lines established in vitro (LCLs). BL cells never express ecto-5'-nucleotidase (5'-N) and exhibit only low levels of ecto-ATPase activity, whereas LCL-cells usually express both enzymes to varying degrees. There is a certain correlation (r = 0.75) between 5'-N and ecto-ATPase. When cAMP formation in response to agonists of the A2-type (stimulating) adenosine receptor is measured in the same cell lines there is no correlation with the expression of ecto-nucleotidases. Within pairs of BL and LCL cell lines derived from the same donor, an inverse relationship between ecto-nucleotidases and the response to the adenosine receptor agonist N-ethyl-carboxamido-adenosine (NECA) is observed. BL cells show a good response to NECA, whereas this is low or absent in LCL cells. Treatment of cells which exhibit both 5'-N and the adenosine receptor with specific polyclonal or monoclonal antibodies against the enzyme does not impair the function of the receptor. Antisera against peptides of the membrane antigen BNLF I-MA, coded by the EBV-genome, do not co-precipitate 5'-N out of detergent extracts of LCL-cells. In both cases 5'-N cannot be closely associated with other membrane components. The differences between BL and LCL cells in ectonucleotidases and the adenosine receptor appear to be fairly stable phenotypical markers, independent of other parameters and suitable for use in distinguishing these cells in all populations.

Localization of NTPDase1/CD39 in Normal and Transformed Human Pancreas

“…Our present work reveals that, in the newly formed regions of cancerous tissue, E-ATPDase activity is diminished in the smooth muscle cells around the ducts and is absent from the connective tissue. Only few and controversial data are available about the relation between NTPDases and tumor formation (e.g., Gutensohn and Jahn 1988;Agteresch et al 1999). The cascade of ectonucleotidases, including NTPDase1, may have a protective function by keeping extracellular ATP and adenosine levels within physiological limits.…”

Evidence for Coordinated Induction and Repression of Ecto-5'-Nucleotidase (CD73) and the A2a Adenosine Receptor in a Human B Cell Line

“…Usually B cells in primary follicles and resting memory B cells are CD73 + while germinal center B cells are CD73 -. Among B cell lines, lymphoblastoid lines (LCLs) are characterized by varying degrees of CD73 expression, whereas the typical Burkitt lymphoma line is usually devoid of CD73 activity (Gutensohn and Jahn, 1988).…”

The importance of B‐cells and ecto‐5′nucleotidase in Mycoplasma fermentans infection and the relevance to rheumatoid arthritis

“…5 0 N is found on Epstein-Barr virus (EBV) transformed B-cell lines, but not on the less mature Burkitt's lymphoma cells. 14 The 5 0 N activity in the serum comes mainly from the liver. In rheumatoid arthritis (RA) patients the 5 0 N enzyme activity in the serum has been shown to correlate strongly with the erythrocyte sedimentation rate (ESR), linking it to inflammation.…”

“…The enzyme is not present on polymorphs, erythrocytes or platelets. 5′N is found on Epstein–Barr virus (EBV) transformed B‐cell lines, but not on the less mature Burkitt's lymphoma cells 14 …”