Defective expression of IL-2 receptors on peripheral blood lymphocytes from patients with cluster headache

In a previous study we demonstrated that cluster headache (CH) patients present an increased Natural Cytotoxic response after incubation of their peripheral blood lymphocytes (PBL) with Interleukin-2 (IL-2). This phenomenon led to an investigation of the phenotypic expression of PBL before and after IL-2 incubation, and of the IL-2 lymphocyte receptor. IL-2 receptor is expressed on T-lymphocytes activated with an high-affinity binding site. The analysis of the function of human IL-2 receptor was facilitated by the production of a specific monoclonal antibody (MAb). This MAb identifies the IL-2 receptors by blocking the binding of radiolabelled IL-2 to T-cells. In addition, we studied the expression of Leu-4, specific for T-cells; of Leu-11b, specific for FC receptor on NK cells; and the Transferrin Receptor, specific for lymphoblasts and monocytes. Twenty-three episodic CH patients were selected for this study. Ten sex and age-matched healthy volunteers were used as the control group. We evaluated the PBL phenotypic expression of cells subsets before incubation with IL-2 (1,000 I.U./ml) and after 72 hours. The following Becton Dickinson MAbs have been used: anti-Leu-4 (CD3), anti-IL-2 receptors (CD25), anti-Transferrin receptor (TFR) and anti-Leu-11b (CD16). Indirect fluorescence with a Becton Dickinson FACS-420 flow cytometer was used to analyze the cells.(ABSTRACT TRUNCATED AT 250 WORDS)