Correlation of α1-Antitrypsin (A1AT), Complement Component C5a and Secretory Immunoglobulin A (sIgA) With Pulmonary Complications; 20 Years After Sulfur Mustard Exposure, Sardasht-Iran Cohort Study

Little is known about pulmonary complications induced by Sulfur Mustard (SM), as a chemical warfare agent, especially considering its long term effects. The present study was carried out to investigate the association of α1-Antitrypsin (A1AT), Complement component C5a, and Secretory Immunoglobulin A (sIgA) with long-term pulmonary complications on SM-exposed individuals, 20 years after the exposure.

Sardasht-Iran Cohort Study (SICS) is a historical cohort study on 372 SM-exposed individuals and 128 age-matched unexposed participants. The clinical evaluations and Spirometry were performed on all the participants according to American Thoracic Society Criteria. Also, we assessed the salivary levels of A1AT, C5a, and sIgA using ELISA assay.

The results indicated significant associations between salivary levels of A1AT, C5a, and sIgA with chronic cough in the exposed victims. Also, there were associations between C5a and sIgA with dyspnea in SM-exposed victims with chronic cough compared with those in the exposed victims without chronic cough. The salivary levels of C5a significantly decreased in severe pulmonary involvement. Moreover, a significant relationship was observed between the salivary levels of C5a and pulmonary function testes.

According to the findings, the salivary level of C5a might reflect the severity of pulmonary involvements following SM exposure. A1AT, as a protective agent, has correlations with cough and dyspnea. Although no strong correlation was found between the salivary levels of these factors with persistence of pulmonary complications, they can be effective in the development and progression of pathological changes in the lungs of the SM-exposed victims.