Basis of Relative Insensitivity of HIV-Infected JM Cells to AZT

Autor: D. L. Taylor, A. S. Tyms, R. D. Snyder, T. M. Brennan
Rok vydání: 1995
Předmět:
Zdroj: Antiviral Chemistry and Chemotherapy. 6:307-311
ISSN: 2040-2066
DOI: 10.1177/095632029500600504
Popis: The basis of azidothymidine (AZT) insensitivity in the human JM T-cell line has been investigated. It was shown that uptake of radiolabelled thymidine or AZT into cellular acid-soluble pools of JM cells was about 10-fold lower than that seen in AZT-sensitive HeLa cells. Thymidylate kinase, however, was apparently not inhibited by AZTMP in JM cells to the extent observed in most cells and, as a result, AZTTP formation proceeded at a greater rate than in HeLa cells, which exhibited accumulation primarily of AZTMP. Thus the deficit in phosphorylation in JM cells cannot solely account for the decreased AZT sensitivity. Instead, it was shown that JM cells excreted AZTMP into the culture medium and that, whereas HeLa cells continued to accumulate AZT nucleotides over time, JM cells did not. This excretion of AZTMP in JM cells also led to a failure to sustain lowered competing TTP pools. It is concluded that it may not be appropriate to use the JM cell line for testing of novel anti-HIV nucleotides designed to circumvent requirements for phosphorylation.
Databáze: OpenAIRE