Abstract

Despite many years having passed since exposure to sulfur mustard (SM) gas, there are many exposed subjects who are still suffering from delayed pulmonary complications. The levels of pro-inflammatory cytokines in the lung of these subjects have not been investigated in delay phase. In this study, we evaluated mRNA expression of pro-inflammatory cytokines (tumor necrosis factor alpha (TNF alpha), tumor necrosis factor receptor type 1 (TNFR1), and interleukin 1 beta (IL-1 beta) in lung biopsy of SM-exposed subjects and compared them with control (non-exposed) subjects. We used formalin-fixed, paraffin-embedded (FFPE) tissue for this purpose. Lung FFPE blocks of SM-exposed subjects (30 samples) and a control group (30 samples) were collected from archival pathology department. The total mRNA of FFPE tissues were extracted and the mRNA expression of pro-inflammatory cytokines were determined by quantitative Real Time PCR (RT-qPCR). The obtained results from two groups were compared to each other and non-parametric statistical analyses were carried out on them. Our studies showed that the mRNA expression of TNF alpha, TNFR1 and IL-1 beta in lung tissue of SM injured and control people have no significant difference (p-value= 0.159, 0.832 and 0.314 respectivly). TNFR1 showed direct correlation with TNF alpha (r=0.867, p=0.002) and IL-1 beta (r= 0.65, p=0.006). The evaluation of mRNA expression in pro-inflammatory cytokines in lung of SM-exposed subjects after 20 years showed that these mediators are similar to those of non-exposed group and there was no acute inflammation in lung of these patients.