We studied the effects of natural and recombinant human IL-2 (rIL-2) on secretion of prostacyclin (PGI2), vWf, and tissue-type plasminogen activator (tPA). IL-2 elicited a steady increase in PGI2 synthesis by cultured human umbilical vein endothelial cells (HUVECS) and bovine aortic endothelial cells but had no effect on vWf or tPA. Both purified natural IL-2 (nIL-2) and rIL-2 induced significant PGI2 synthesis. Substitution of the cysteine residue at position 125 of rIL-2 with serine or alanine led to loss of PGI2-stimulatory activity in HUVECS without affecting thymidine incorporation in lymphocytes. HPLC analysis of arachidonate metabolites detected predominantly 6 keto-PGF1 alpha (6KPGF1 alpha) peak. Treatment of cultured endothelial cells with cycloheximide and actinomycin D resulted in inhibition of 6KPGF1 alpha synthesis. The Western blot using a polyclonal antibody against PGH synthase revealed an increment in the 70-kD subunit of PGH synthase by nIL-2 and rIL-2, but not by alanine-substituted rIL-2. We conclude that IL-2 stimulated sustained PGI2 production by a mechanism that includes the de novo synthesis of PGH synthase. This mechanism for regulating AA metabolism probably has important physiologic implications.
K Frasier-Scott, H Hatzakis, D Seong, C M Jones, K K Wu
Usage data is cumulative from April 2023 through April 2024.
Usage | JCI | PMC |
---|---|---|
Text version | 83 | 0 |
62 | 21 | |
Figure | 0 | 3 |
Scanned page | 117 | 10 |
Citation downloads | 5 | 0 |
Totals | 267 | 34 |
Total Views | 301 |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.