EXPRESSION OF ENDOCANNABINOID CB2 RECEPTOR BY IMMUNE CELLS AT CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Abstract

The expression level of endocannabinoid CB₂ receptor at mononuclear leukocytes of patients with chronic obstructive pulmonary disease (COPD) with various degrees of severity was studied. 65 patients were examined including 37 people with COPD of I-II stages in remission and 28 healthy volunteers. The blood serum was studied to estimate the level of tumor necrosis factor (TNF-α), its receptor (s-TNFa RI (p55)), interleukin-8 (IL-8), basic growth factor of fibroblasts (bFGF) and transforming growth factor β1 (TFGβ1). CB₂ receptor expression was studied at mononuclear leukocytes by flow cytofluorometry. It is shown that with the worsening of the disease (COPD II stage) the imbalance of cytokine production towards the growth of TNF-α, bFGF, TGF-β and reduction of IL-8 increases, which indicates the presence of a systemic inflammatory response and deregulation of signaling mechanisms of the immune response. The study of the expression level of CB₂ receptor in patients with COPD of I stage revealed a slight decrease in the number of immune cells expressing CB₂ receptor. In patients with COPD of II stage the number of mononuclear leukocytes expressing CB₂ receptor decreased 2.3 times in comparison with healthy patients. Thus, the cellular and molecular mechanism of chronic inflammation at COPD is associated with the violation of the CB₂ receptor expression. The less CB₂ receptor is expressed, the more the impaired regulation of the immune response is, which indicates the reciprocal nature of the integration of the immune system and endocannabinoid system.