Differential regulation of interleukin-1alpha and interleukin-1beta in K-562 cells.
Interleukin (IL)-1alpha and IL-1beta are encoded by two separate genes, but both function as comitogens for lymphocyte activation. In this study, we observed K-562 cells to express constitutively mRNA for IL-1alpha, although IL-1alpha was not detected in the growth-conditioned medium (GCM). However, IL-1beta mRNA was not expressed unless the cells had been treated with phorbol myristate acetate (PMA). Both IL-1alpha and IL-1beta were detected in the GCM after the cells had been cultured with PMA, suggesting that IL-1 elaboration required PMA treatment. The K-562 cells treated with PMA differentiated to the myeloblastic stage, as observed by nuclear morphologic properties by electron microscopy. PMA treatment induced de novo expression of CD61 or gpIIIa, a marker associated with megakaryoblasts. These results showed that although K-562 cells constitutively expressed IL-1alpha mRNA, PMA treatment was required for secretion. On the other hand, both the expression and secretion of IL-1beta required treatment with PMA. This study showed that K-562 cells treated with PMA differentiated to the myeloblastic stage and expressed and secreted IL-1alpha and IL-1beta.
Ichiki
A T
AT
Graduate School of Medicine, University of Tennessee Medical Center at Knoxville, 37920, USA. aichiki@mc.utmck.edu
Langenberg
M
M
Baker
E J
EJ
Hodge
J W
JW
Bamberger
E G
EG
Gerard
D A
DA
Lozzio
C B
CB
D002455:Cell Division / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D007375:Interleukin-1; D012333:RNA, Messenger; D013755:Tetradecanoylphorbol Acetate