Differential effects of IL-2 and IL-15 on expression of IL-2 receptor alpha.
IL-2 and IL-15 have overlapping functions since they share the IL-2Rbetagamma receptor complex. However, each cytokine has a private alpha receptor namely IL-2Ralpha for IL-2 and IL-15Ralpha for IL-15. As a consequence the effects of the two cytokines may differ. We describe the differential effects of the two cytokines regarding the induction of cell surface expression of the IL-2Ralpha subunit on YT-l cells. Both cytokines induced transcription of the IL-2Ralpha gene. Furthermore translation of IL-2Ralpha leading to intracellular expression of the receptor was observed following either IL-2 or IL-15 addition. However, only IL-15 was associated with the induction of cell surface expression of IL-2Ralpha. With IL-2 there appears to be an impediment to the translocation of IL-2Ralpha to the cell membrane. Since surface expression of IL-2Ralpha is a key element in the formation of the high affinity IL-2 receptor, translocation of IL-2Ralpha to the membrane represents another level of control of the immune response in addition to regulation of IL-2Ralpha transcription and translation.
Alileche
A
A
Metabolism Branch, National Cancer Institute, NIH, Bethesda, Maryland 20892, USA.
Goldman
C K
CK
Waldmann
T A
TA
D015152:Blotting, Northern; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D019409:Interleukin-15 / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D021122:Protein Subunits; D021381:Protein Transport / Q000187:drug effects; D012333:RNA, Messenger / Q000096:biosynthesis; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects
D019409:Interleukin-15; D007376:Interleukin-2; D021122:Protein Subunits; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2