Acid anhydrides are a group of highly reactive chemicals used widely in the formulation of paints and plastics. Exposure to
acid anhydrides causes several occupational
lung diseases such as pneumonititis and
asthma. Whilst
anhydrides, specifically
trimellitic anhydride (TMA), have been shown to bind to lung tissue in an animal model, further investigation has been hampered by the lack of a
reagent which would enable the identification of primary target
proteins for the binding of TMA. Our objective was to develop an antibody to TMA which would enable in vitro studies of TMA interactions with lung epithelial
proteins. We developed a
monoclonal antibody which binds solely to TMA. We have demonstrated that the antibody can be used to detect TMA bound to different human
proteins with little non-specific binding to unconjugated
proteins. We then exposed cells of the A549 lung epithelial cell line to TMA in vitro and have shown by western blotting that binding occurs in the 20-35 Kd weight range. We have developed a specific and sensitive
reagent to detect TMA bound to
proteins. We have used this to show that when TMA is incubated with a lung epithelial cell line, that the TMA binds to
proteins with a restricted molecular weight range. These results suggest that the current paradigm for the detection of
IgE to small molecular weight reactive chemicals, which presupposes that the chemical binds to
serum albumin, may need further investigation.