Vol 56, No 5 (2005)
Original paper
Published online: 2006-05-28
Evaluation of the effect of GHRH(1-44)NH2 on the secretion of interleukin-2 (IL-2) and soluble IL-2 receptor α (sIL-2Rα) from human peripheral blood mononuclear cells in vitro
Endokrynol Pol 2005;56(5):773-780.
Abstract
Objective: The bidirectional communication between the
neuroendocrine and the immune systems is now a subject
of an intensive investigation. Somatoliberin (GHRH) is a
hypothalamic hormone that enhances the synthesis and
the release of growth hormone (GH) from the anterior
pituitary cells. Few recent reports demonstrate also role
of the neuropeptide in the regulation of the immune
system function.
Aim: The aim of the study was to examine the influence of GHRH on IL -2 as well as sIL -2Rα secretion from mitogen-stimulated peripheral blood mononuclear cells.
Material and method: Mononuclear cells (PBMC) were isolated from the peripheral blood of healthy adults according to the technique described by Böyum. Cells, cultured 24 hours at 370 C in humudified atmosphere of 95% air and 5% CO2, were stimulated with phytohemaglutinin (PHA; 10 µg/ml), and then GHRH(1-44)NH2 at the final concentrations 10-12, 10-10, 10-8 and 10-6 M was added to appropriate wells. ELISA kits were used to measure IL-2 and sIL-2Rα concentrations in the supernatants of cultured cells. Comparisons between tested groups were made by U Mann-Whitney test. The differences were considered significant if p < 0.05.
Results: GHRH stimulated the secretion of IL -2 into the supernatants acting significantly at the concentration of 10-12M (p < 0.001). Moreover, GHRH at concentrations 10-10M and 10-8M significantly increased the secretion of sIL-2Rα as well (p < 0.001). Strong positive correlation between tested GHRH concentrations and sIL-2Rα levels in the supernatants was demonstrated (r = 0.8664; p < 0.001).
Conclusions: The results demonstrate the potential involvement of GHRH in the regulation of T lymphocytes secretory function.
Aim: The aim of the study was to examine the influence of GHRH on IL -2 as well as sIL -2Rα secretion from mitogen-stimulated peripheral blood mononuclear cells.
Material and method: Mononuclear cells (PBMC) were isolated from the peripheral blood of healthy adults according to the technique described by Böyum. Cells, cultured 24 hours at 370 C in humudified atmosphere of 95% air and 5% CO2, were stimulated with phytohemaglutinin (PHA; 10 µg/ml), and then GHRH(1-44)NH2 at the final concentrations 10-12, 10-10, 10-8 and 10-6 M was added to appropriate wells. ELISA kits were used to measure IL-2 and sIL-2Rα concentrations in the supernatants of cultured cells. Comparisons between tested groups were made by U Mann-Whitney test. The differences were considered significant if p < 0.05.
Results: GHRH stimulated the secretion of IL -2 into the supernatants acting significantly at the concentration of 10-12M (p < 0.001). Moreover, GHRH at concentrations 10-10M and 10-8M significantly increased the secretion of sIL-2Rα as well (p < 0.001). Strong positive correlation between tested GHRH concentrations and sIL-2Rα levels in the supernatants was demonstrated (r = 0.8664; p < 0.001).
Conclusions: The results demonstrate the potential involvement of GHRH in the regulation of T lymphocytes secretory function.
Keywords: interleukin-2interleukin-2 receptorsomatoliberinneuroimmunomodulation