Interleukin 2 up-regulates glucocorticoid receptor number in human peripheral blood mononuclear cells and the osteosarcoma cell line Saos-2 in vitro.
Glucocorticoids are well-recognized modulators of immunocytes and osteoblasts via specific receptor-mediated mechanisms. We have evaluated the in vitro effect of interleukin 2 (IL-2) on the expression of glucocorticoid receptors (GRs) in peripheral blood mononuclear cells (PBMCs) obtained from healthy donors and osteoblast-like Saos-2 cells. Aliquots of PBMC or Saos-2 cells were incubated for 20 h in the presence or absence of recombinant human IL-2 (100 IU/mL) at 37 degrees C. After incubation, a [3H]dexamethasone radioligand-binding assay and Scatchard analysis were used to determine GR-binding parameters in both cell populations. Saos-2 cells basally express higher numbers of GR than PBMCs. After IL-2, a significant increase in GR number was found for both PBMCs and Saos-2 cells. The relative increase was higher in Saos-2 cells; in PBMCs, the apparent affinity fell to almost half. These data represent an additional piece of evidence that cytokine and steroid hormones may act in a complementary way to regulate specific cell functions.
Sartori
M L
ML
Cattedra di Medicina Interna, Università degli Studi di Torino, Azienda Ospedaliera S. Luigi, Orbassano, Torino, Italy.
Masera
R G
RG
Staurenghi
A
A
Racca
S
S
Angeli
A
A
D000328:Adult; D005260:Female; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism; D011485:Protein Binding; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000187:drug effects*
D007376:Interleukin-2; D011965:Receptors, Glucocorticoid; D011994:Recombinant Proteins