The immune status indices and their interaction with growth hormone and insulin-like growth factor-I levels in acromegaly

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 109-133-GHRH, GH & IGF Biology & Signaling
Bench to Bedside
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-131
Margarita Dudina*1, Sergey Dogadin2 and Andrey Savchenko3
1Krasnoyarsk State Medical University named after Prof. V. F. Voino-Yasenetsky, Krasnoyarsk, Russia, 2Krasnoyarsk Regional Clinical Hospital, Krasnoyarsk, Russia, 3Institute for Medical Problems of the North, Siberian Division, Russian Academy of Medical Sciences, Krasnoyarsk, Russia
Neuroendocrine and immune systems have a close relationship that involved in the regulation of systemic homeostasis. A positive effect of growth hormone (GH) on erythropoiesis, proliferation of T-cells, the acceleration of hematopoiesis and inhibition of lymphoproliferation after the introduction of antibodies to GH have been revealed. Aim: To study the immune status indices and their interaction with GH  and insulin-like growth factor I (IGF-I) levels  in patients with acromegaly. Methods: The study population consist 88 (83.0%) patients with active acromegaly and 18 (17.0%) with laboratory remission (LR), mean age - 51,8 ± 11,9 years. The immune status indices were assessed by indirect immunofluorescence method using the FITC--labeled monoclonal antibodies to CD3+ -, CD4+ -, CD8+ -, CD16+ -, CD19+ -, CD25+ -, CD95+-cells. Additionally the CD4+/CD8+ ratio was counted. The concentration of immunoglobulins (Ig) A, M, G was assessed by ELISA. The  humoral immunity characterized, also, by the level of relative synthesis IgA (IgA/CD19+), IgM (Ig M/CD19+) and IgG (IgG/CD19+). Results: Regardless of the stage of disease in patients with acromegaly increased  the relative amount of CD3+-, CD8+-cells, the relative and absolute number of CD16+ - and the percentage level of CD19 +-lymphocytes. The number of lymphocytes expressing CD25- and CD95-receptor, in patients with acromegaly improved in both groups, but the rate of percentage  and absolute number increasing of cells with activation receptors is more pronounced in LR patients than in active acromegaly stage. There was no statistically significant changes in CD4+/CD8+ ratio. In active acromegaly patients  the GH level correlated with the percentage of CD3+- (r = +0,45, p = 0,044), CD4+-cells (r = +0,50, p = 0.025), and the IGF-I level with a relative and absolute content of CD3+-lymphocytes (r = +0,59, p = 0.006 and r = +0,60, p = 0.005). In LR group GH level correlated with relative abundance of CD16+ - (r = +0,71, p = 0,033), CD19+-cells (r = +0,71, p = 0,031), IgA (r = +0,79, p = 0,012), IgG (r = +0,70, p = 0.035), and the IGF-I concentration with IgG (r = +0,75, p = 0.020) level. Conclusions: The identified changes in immune status indices and their interaction with pathological GH/IGF-I levels can promote the immune deficiency in chronic hypersecretion of growth factors. It is assumed that such disorders play an important role in neoplastic complications development  of acromegaly.

(1)  Tenore A, Neuroimm Biol 2002; 2: 67-86. (2)  Colao A et al., Clin Endocrinol (Oxf) 1997; 47: 23-28.  (3)  Colao A et al NeuroImm Biol  2002;  2: 247-257.

Nothing to Disclose: MD, SD, AS

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