Innate Immune System Status of Sulphur Mustard-Poisoned Iranian Veterans Three Decades after Exposure

Sulphur mustard (SM) is an incapacitating chemical warfare agent which causes acute and chronic toxicities in different body organs of affected individuals. The aim of this study was to investigate the innate immune status of the Iranian veterans who were exposed to SM around 30 years earlier and had more than 25% disabilities. In this regard, most functional and non-functional parameters of innate immunity were evaluated in 35 veterans. Phagocytic activity, nitroblue tetrazolium (NBT) reduction assay and haemolytic complement activity (HCA) in addition to routine haematological parameters, serum protein electrophoresis, complements C3 and C4 levels were studied. Measures of haematological parameters, serum proteins, C3 and C4 were almost within the normal range. Functional experiments such as phagocytic activity, NBT reduction assay and HCA were normal as well. However, serum protein analysis revealed a fair decrease in percentages of α₁ -globulin. Mean values of the parameters of innate immune system of the veterans three decades after SM poisoning were almost within the upper and lower normal limits. Reduced α₁ -globulin - maybe subsequent to a chain of SM-induced genetic disorders - may have been the result of α₁ -antitrypsin deficiency which may result in prevalent respiratory complications among these veterans. As a supplementary study, measurement of serum α₁ -antitrypsin in SM-poisoned veterans could be beneficial. Further studies are required to prove this hypothesis. Further investigations on the evaluation of the acquired immunity parameters as the second line of defence may reveal a better understanding of SM veterans' immune system status.