Comparison of IgE Antibody Concentrations to Pyromellitic Dianhydride-Modified Laminin and Human Serum Albumin in Sera of Exposed Workers with Respiratory Complaints

Background: Acid anhydrides are used in a variety of industrial branches because of their highly reactive anhydride groups. Adverse effects of anhydride exposure include toxic/irritative effects as well as IgE- and IgG-mediated respiratory disorders. It was the aim of this study to examine the usefulness of conjugates of pyromellitic dianhydride (PMDA) and laminin, a respiratory tract protein, for the in vitro diagnosis of sensitization to PMDA. Methods: Sera of PMDA-exposed workers (n = 9) and nonexposed controls (n = 8) were tested with an enzyme allergosorbent test (EAST). Human laminin and human serum albumin (HSA) were derivatized with PMDA and used as solid-phase in a commercial assay. Results: Seven out of 9 exposed workers revealed elevated IgE antibody concentrations (>0.35 kU/l) against laminin-PMDA whereas 5 of 9 subjects had elevated IgE antibody concentrations to HSA-PMDA. All 9 workers had elevated IgE antibody concentrations in at least one of the two tests. Of the 4 workers who complained of shortness of breath, 3 were positive for laminin-PMDA and 2 for HSA-PMDA. All of the nonexposed subjects were negative (