| Summary: | 碩士 === 國立陽明大學 === 藥理學研究所 === 88 === Abstract
Human interleukin-2 (IL-2) is a pleiotropic cytokine that regulates many essential immune functions, including the growth and differentiation of lymphocytes. Recent reports indicate that IL-2 is effective in metastatic melanoma and renal cell carcinoma therapies, and also capable of diminishing the pool of latently infected CD4+ T cells in HIV-infected patients receiving antiviral therapy. However, clinical applications of IL-2 were restricted by the severe side effects resulting from direct administration of this cytokine. In this regard, selective small molecule IL-2 inducers may be good replacements because administration of these agents might result in an effective but not a toxic level of this cytokine in the circulation.
For this purpose, we constructed a high-throughput model cell system and examined its responsiveness to a variety of immuno- stimulators and immunosuppressants. Our system was based on the production of secreted alkaline phosphatase (SEAP) from Jurkat cells stably transfected with its corresponding gene whose expression was under control of a human IL-2 promoter. A clone whose SEAP production was increased dramatically after PMA plus calcimycin (A23187) treatment was identified and named JKHR-1. The increase in enzyme activity in these cells was preceded by an increase in its mRNA, indicating activation of the reporter gene occurring mainly at the level of transcription.
Induction of SEAP synthesis was also observed when this clone was treated with T-cell mitogens PHA, Con A, jacalin, PMA/PHA, and anti-CD3/anti-CD28 antibodies. In contrast, SEAP production from JKHR-1 cells activated by PMA plus PHA was completely abolished by pretreatment with cyclosporin A, FK-506, U0126, or SB203580, but not dexamethasone or mycophenolic acid. Taken together, this stable T-cell line appeared to be useful in high-throughput screening for both inducers and repressors of human IL-2 production.
|
|---|
