Correlation between density of beta 2-adrenergic receptors on peripheral blood mononuclear cells and serum levels of soluble interleukin-2 receptors in patients with chronic inflammatory diseases.

In order to study the influence of the autonomic nervous system on the immune response, we evaluated the density and the equilibrium dissociation constants (KD) of beta 2-adrenergic receptors (beta 2R) on peripheral blood mononuclear cells (PBMC) in patients with rheumatoid arthritis (RA), Crohn's disease (CD), and in controls. Results were correlated with the serum concentrations of soluble interleukin-2 receptors (sIL-2R) as a marker for T-cell activation in vivo. The density of beta 2R was significantly decreased in patients with RA (P < 0.05) and CD (P < 0.05) as compared with controls. The number of beta 2R in patients with RA was significantly lower than in CD patients (P < 0.05). KD values of beta 2R were markedly but not significantly decreased in both patient groups as compared with control values. Serum concentrations of sIL-2R were significantly elevated in RA patients as compared with those in CD patients (P < 0.05) and controls (P < 0.05), while there was no difference between the latter two groups. In patients with RA, a significant negative correlation between beta 2R density and serum IL-2R levels (r = -0.66, P < 0.02) was observed. These results demonstrate the close correlation between the modulation of beta 2R on PBMC and the activation of the immune response. However, the role of beta 2R stimulation in the pathogenesis of immunologically mediated diseases remains to be clarified.