Growth hormone restores glucocorticoid-induced T cell suppression.

Abstract

SPECIFIC AIMSGrowth hormone (GH) has been extended to the improvement of metabolic imbalance in many diseases, including autoimmune disease treated with glucocorticoids (GCs), but it is unclear whether GH can be used safely in autoimmune disorders that are treated with GC. Here we focused on the effect of GH on peripheral T lymphocytes under GC excess.PRINCIPAL FINDINGSExpression of GHR mRNA and tyrosine phosphorylation of JAK2 and STAT5b in human peripheral T lymphocytesWe investigated the expression of GHR mRNA in human peripheral T lymphocytes (HPTL) and peripheral mononuclear cells (PBMC). GHR mRNA was detected in both cell fractions by RT-PCR Southern blotting using a pair of primers set on exons 4 and 6 (Fig. 1A⤻ ). The expression of GHR mRNA was down-regulated by treatment with recombinant human GH (rhGH) (data not shown). To determine whether GH can stimulate tyrosine phosphorylation of cellular proteins in HPTL, the cells were treated with rhGH. Recombinant hGH stimulated the tyrosine phosphoryla...