TY - JOUR T1 - Occupational asthma from nickel sensitivity: II. Factors influencing the interaction of Ni2+, HSA, and serum antibodies with nickel related specificity. JF - British Journal of Industrial Medicine JO - Br J Ind Med SP - 56 LP - 63 DO - 10.1136/oem.41.1.56 VL - 41 IS - 1 AU - E Nieboer AU - S L Evans AU - J Dolovich Y1 - 1984/02/01 UR - http://oem.bmj.com/content/41/1/56.abstract N2 - Serum from an individual with occupational asthma from nickel sulphate inhalation was shown by ammonium sulphate (Farr) and anti-IgG coprecipitation tests to contain antibodies which bind 63Ni2+. This binding was absent from 30 control sera. Ligand competition studies with serum and plasma from the propositus and controls are described, and include serial additions of HSA, L-histidine, EDTA, and the tripeptide gly-gly-L-his. The results, like those from metal ion blocking experiments, clearly showed that the formation of the reactive antigenic determinant depends on the selective binding of Ni2+ at the native Cu2+/Ni2+ transport site of HSA. Corroborating evidence is derived from the similar dependence on pH of the Ni2+-HSA formation and the ammonium sulphate 63Ni2+ coprecipitation reactions. ER -