Antibody response to trimellityl hemoglobin in trimellitic anhydride-induced lung injury

Sprague-Dawley rats were exposed to trimellitic anhydride by inhalation, and the antibody response to trimellityl (TM)-conjugated hemoglobin (HB) and TM rat serum albumin (RSA) was compared. Groups of rats were exposed to trimellitic anhydride by inhalation 6 hours per day for 2, 6, or 10 days at 100 micrograms/m3 and compared to a control group exposed to filtered air. The IgG antibody response to TM-HB in both serum and bronchoalveolar lavage (BAL) fluid was measured with ELISA. IgG antibody levels to TM-HB rose significantly throughout the exposure. A positive correlation was found between IgG to TM-HB in serum and BAL fluid. In addition, this response in both serum and BAL fluid correlated with the IgG antibody response to TM-RSA. Cross-inhibition studies indicated the existence of shared antigenic determinants on TM-RSA and TM-HB. The IgG antibody to both antigens was specific for new antigenic determinants and not for the TM hapten.