Role of β-chemokines in allergic diseases

Inflammation represents the key event in the pathogenesis of allergic diseases. Several mediators, produced by immune and non immune cells, are known to play a role in inflammation. Recently chemokines of the C-C (β) family have been identified to possess both histamine-releasing and eosinophil-activating properties. We selected 26 patients affected by chronic urticaria (CU) and compared serum b chemokine levels with those of healthy nonatopic controls and subjects with allergic asthma and/or rhinitis. We further subdivided CU patients according to intradermal (ID) reaction to autologous serum - a test claimed to discriminate a possible autoimmune pathogenesis. 20 CU patients had a positive ID test, and 7 of them turned negative with improvement of symptoms. Serum levels of the chemokines RANTES, MCP-1, and MIP-1a (measured by ELISA) were increased in patients with respiratory allergy but only slightly in CU. However we observed a significant decrease of β chemokines in cases of CU after their ID test turned negative. These findings point to the possible involvement of β chemokines as mediators of allergic inflammation both in respiratory allergy and in urticarial syndromes, where they may exert histamine-releasing activity.