CIRCULATING NERVE GROWTH-FACTOR LEVELS ARE INCREASED IN HUMANS WITH ALLERGIC DISEASES AND ASTHMA

Nerve growth factor (NGF) serum levels were measured in 49 patients wi th asthma and/or rhinoconjunctivitis and/or urticaria-angioedema. Clin ical and biochemical parameters, such as bronchial reactivity, total a nd specific serum IgE levels, and circulating eosinophil cationic prot ein levels, were evaluated in relation to NGF values in asthma patient s, NGF was significantly increased in the 42 allergic (skin-test- or r adioallergosorbent-test-positive) subjects (49.7 +/- 28.8 pg/ml) versu s the 18 matched controls (3.8 +/- 1.7 pg/ml; P < 0.001), NGF levels i n allergic patients with asthma, rhinoconjunctivitis, and urticaria-an gioedema were 132.1 +/- 90.8, 17.6 +/- 6.1, and 7.6 +/- 1.8 pg/ml (P < 0.001, P < 0.002, and P < 0.05 versus controls), respectively. Patien ts with more than one allergic disease had higher NGF serum values tha n those with a single disease, When asthma patients were considered as a group, NGF serum values (87.6 +/- 59.8 pg/ml) were still significan tly higher than those of control groups (P < 0.001), but allergic asth ma patients had elevated NGF serum levels compared with nonallergic as thma patients (132.1 +/- 90.8 versus 4.9 +/- 2.9 pg/ml; P < 0.001), NG F serum levels correlate to total IgE serum values (rho = 0.43; P < 0. 02), The highest NGF values were found in patients with severe allergi c asthma, a high degree of bronchial hyperreactivity, and high total I gE and eosinophil cationic protein serum levels, This study represents the first observation (that we know of) that NGF is increased in huma n allergic inflammatory diseases and asthma.