Are serum levels of immunoglobulin classes and IgG subclasses involved in delayed pulmonary complications induced by sulfur mustard? Sardasht-Iran Cohort Study.

Respiratory complications are the foremost long term debilitating effects after sulfur mustard toxicity. The underlying immunological mechanisms of sulfur mustard induced lung damage are still poorly understood. The question of the involvement of immunoglobulin classes and subclasses in delayed pulmonary complications induced by SM was addressed in this study as a part of Sardasht-Iran Cohort Study (SICS).In SICS, 372 male participants who were exposed to SM 20 years earlier were compared with 128 unexposed age-matched controls. At the time of study (2007), the clinical evaluations and spirometry was performed for all subjects according to the American Thoracic Society Criteria, and at the same time, the sera were isolated, labeled and aliquots were kept frozen in -80°C. Serum immunoglobulin (Ig) levels including IgM, IgA, IgE, IgG, and IgG subclasses (IgG1, IgG2, IgG3 and IgG4) were measured using quantitative Elisa method. It was found that among immunoglobulin classes and IgG subclasses only IgM and IgG4 were significantly decreased in the peripheral blood of exposed cases. IgM level also positively correlated with FEV1 only in the SM exposed group. These results indicated a weak but significant role for IgA in control of the delayed pulmonary complications. There were no strong correlations between other immunoglobulin classes or IgG subclasses with pulmonary disease severity in sulfur mustard intoxicated subjects. The authors proposed that systemic levels of immunoglobulins do not exert essential roles in severity of delayed pulmonary complications following SM toxicity. However, more studies on local and systemic levels of immunoglobulins in more severe groups are suggested.

Long term impact of sulfur mustard exposure on peripheral blood mononuclear subpopulations--Sardasht-Iran Cohort Study (SICS).

The most important long-term morbidity problem of sulfur mustard (SM) toxicity is pulmonary complications but the pathogenesis of these complications is not clearly understood. This study evaluates the peripheral blood mononuclear sub-sets and their correlation with pulmonary function in SM exposed civilian cases 20 years post-exposure as gathered in the context of the Sardasht-Iran Cohort Study (SICS). Samples were randomly selected from two groups, SM-exposed (n=372) and control (n=128), with the same ethnicity, culture, and demography. Three color flow cytometry was applied for peripheral blood mononuclear sub-population determination. Results indicated a significant decrease in CD45+/CD3+, CD45+/CD3+/CD4+, and an increase in CD3+/CD16+56+ percentages. It was also found that absolute count of NK cells was highly increased in peripheral blood of exposed cases. There was a significant increase in NK cell count of SM exposed group with pulmonary problems as compared to the same group without pulmonary problems (p-value<0.04) based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD). The findings showed a significant negative correlation between absolute numbers of T lymphocyte and FVC % and positive correlation with FEV1/FVC%. The results also demonstrated that absolute numbers of monocytes had a negative correlation with FVC %. We propose that NK and T cells are probably involved in the pathogenesis or immune reactions to the delayed pulmonary complications induced by SM. This hypothesis should be tested in a more severe pulmonary complicated group.

Serum albumin and paraoxonase activity in Iranian veterans 20 years after sulfur mustard exposure.

Sulfur mustard, a chemical warfare agent, has short- and long-term effects on various organs including respiratory system. Its late toxic effects on biological macromolecules among exposed veterans have not been well studied. We performed a study to determine paraoxonase-1 (PON1) activity and phenotype distribution as well as its correlation with albumin level in 289 male veterans with severe pulmonary complications who had exposure to sulfur mustard 20 years ago and in 66 age and ethnic matched healthy male subjects as controls. Serum albumin levels were lower in the veterans compared to controls (P < 0.001). Mean basal PON1 activity was 91.61 ± 44.80 U/mL in the veteran group versus 110.27 ± 50.23 U/mL in controls (P = 0.005). Arylesterase activity was not significantly different between the two groups. Paraoxonase to arylesterase activity ratio was significantly lower in the veterans as compared to controls (P = 0.005), mainly indicative of decreased PON1 activity rather the enzyme level. Significant reduction was found in serum albumin and PON1 activity with disease severity. Moreover, decreased high active BB (high activity) phenotype and increased intermediate active AB (moderate activity) phenotype were found in the veterans. This condition may lead to long-term accumulation of reactive oxygen metabolites resulting in a pro-oxidation milieu, which in turn can lead to increased peroxide levels and decreased antioxidant PON1 activity. In conclusion, lower serum PON1 activity and albumin might contribute to morbidity and occurrence of other complications such as atherosclerosis and rapid aging in the veterans suffering from late toxic effects of sulfur mustard.

Association of physical activity and IL-10 levels 20 years after sulfur mustard exposure: Sardasht-Iran cohort study.

IL-10 is an anti-inflammatory cytokine that is important in the regulation of inflammatory processes in different conditions. Sulfur mustard (SM) intoxicated patients are suffering from different inflammatory diseases in their lung, skin and eyes. Physical activity (PA) is reported to control inflammation by reducing pro-inflammatory and inducing anti-inflammatory cytokines. Our previous study revealed lower PA and more sedentary lifestyle among SM exposed population. This study aimed to determine the relationship of PA with IL-10 production in SM exposed subjects. Baseline, mitogen-induced and the serum levels of IL-10 were evaluated. In a historical cohort study, Sardasht-Iran Cohort Study (SICS), 372 SM exposed participants were studied 20 years after exposure and were compared with 128 unexposed control participants. The Global Physical Activity Questionnaire (GPAQ; developed by WHO) was used to obtain a self-reported measure of physical activity. Whole blood culture supernatants and serum samples were used for IL-10 measurement by ELISA technique. In both the control and exposed groups mitogen-induced IL-10 production was significantly elevated with severity of PA intensity (p<0.05). In the control subjects with moderate PA intensity, the mitogen-induced IL-10 production was higher than the corresponding in the exposed group (p<0.05). In the exposed group, mitogen-induced IL-10 production had significant positive correlation with total PA, total transport PA, total recreational PA and total moderate intensity work (p<0.05). The positive relationship between high PA and the levels of anti-inflammatory cytokine IL-10 indicates a need to encourage a more active lifestyle among the SM exposed subjects who have various inflammatory complications.

Evaluation of relationship between the serum levels of inflammatory mediators and ocular injuries induced by sulfur mustard: Sardasht-Iran Cohort Study.

Ocular damages induced by sulfur mustard (SM) are the important problems in exposed patients. The damaging mechanisms are not clearly understood. In the present study the relationship between the serum levels of inflammatory mediators and ocular injuries induced by SM was evaluated. Bulbar conjunctiva and limbal tissue abnormalities were significantly more frequent in the expose versus control group (P=0.004 and 0.048 respectively). The serum levels of IL-1alpha and TNF-alpha in the exposed group with and without Slit lamp findings were significantly lower than their counterpart in the control group. The serum levels of IL-1beta in the exposed group with Slit lamp findings were significantly lower than their counterpart in the control group. The serum levels of IL-1beta in the controls with Slit lamp findings were significantly higher than the controls without Slit lamp findings. The serum levels of IL-1Ra and MMP-9 in the exposed group with and without Slit lamp findings do not display any significant differences as compared to the similar controls. The serum levels of IL-6 in the exposed group with or without Slit lamp findings were significantly lower than their counterpart in the control group (P=0.048 and 0.008 respectively). The serum titers of the CRP and RF in the exposed group without Slit lamp findings were significantly elevated versus their counterpart in the control group (P=0.004 and 0.011 respectively). The serum levels of these inflammatory cytokines except for IL-1Ra and MMP-9, decreased in SM exposed subject independent of ocular problems. More local studies on the eyes are needed to clarify the exact role of this cytokines in ocular problems of chemical.

Alterations in serum levels of inflammatory cytokines (TNF, IL-1alpha, IL-1beta and IL-1Ra) 20 years after sulfur mustard exposure: Sardasht-Iran cohort study.

Mustard gas, even in low doses, has the ability to inflict damage in multiple organs especially the skin, eyes, as well as the respiratory tract. This damage may cause many complications which persist during the lifespan of exposed subjects. Pro-inflammatory cytokines including TNF, IL-1alpha, IL-1beta and IL-1Ra cause systemic inflammatory reactions and numerous changes including altered cell signaling and migration, changes in cytokine production and fever. The aim of this study was to determine the serum levels of these cytokines in subjects who were exposed to mustard gas 20 years ago in comparison with an unexposed control group. In this historical cohort study 368 sulfur mustard (SM) exposed participants from Sardasht and 126 age-matched unexposed volunteers from Rabat (a nearby town) as controls were chosen by a random systematic sampling. The serum concentrations of IL-1alpha, IL-1beta, IL-1Ra and TNF were measured by a sandwich ELISA technique. Median of the serum levels of cytokines TNF, IL-1alpha, IL-1beta and IL-1Ra in the control group was 23.79, 1.89, 1.91 and 32.9 pg/ml respectively, while in the SM-exposed participants these values were 11.11, 0.81, 1.73 and 26.7 pg/ml respectively. The serum pro-inflammatory cytokine levels were significantly lower in the exposed group than in controls (p<0.01). There was also significant positive correlation between concentration of all of mentioned cytokines, the strongest being between IL-1beta and TNF (r=0.809 in the control group). The observed down-regulation of pro-inflammatory cytokines should be considered in interpretation of diagnosis and therapeutic measures taken to improve clinical complications.

Serum levels of IL-8 and IL-6 in the long term pulmonary complications induced by sulfur mustard: Sardasht-Iran Cohort Study.

Sulfur mustard (SM) is a blistering chemical agent which has short and long term toxicity against many organs. The respiratory tract is one of the main targets, and is the most disabling long term complication of SM. Inflammatory mediators especially IL-8 and IL-6 play the primary role in the various chronic pulmonary diseases. Sardasht-Iran Cohort Study (SICS) was designed to evaluate immunological and molecular parameters in SM exposed people 20 years after exposure. In the present study, the association of the serum levels of IL-8, IL-6, C reactive protein (CRP) and rheumatoid factor (RF) with long term pulmonary involvement was evaluated. There were 348 exposed and 120 control participants. The clinical evaluations were done for all subjects and Spirometry was performed according to American Thoracic Society Criteria. Severity of pulmonary involvement was assessed by Global Initiative for chronic Obstructive Lung Disease (GOLD) classification. The serum levels of IL-8, IL-6 and RF were assessed by ELISA assay. CRP was assessed by photometric method. The serum levels of IL-8 and IL-6 significantly decreased in the SM exposed participants compared to the control group. There were no significant associations between the serum levels of IL-8 and pulmonary symptoms (chronic cough, sputum, hemoptysis, and dyspnea), pulmonary findings (crackles, rales, and wheezing) as well as spirometry parameters. IL-6 was associated with wheezing and CRP was associated with wheezing and rales in SM exposed group. We concluded the serum levels of these inflammatory mediators probably do not have any major role in pathogenesis and persistence of pulmonary complications and do not reflect the degree of severity of pulmonary involvement following SM exposure.

Alterations in the serum levels of soluble L, P and E-selectin 20 years after sulfur mustard exposure: Sardasht-Iran Cohort Study.

The selectins (L, P and E) are carbohydrate-binding membrane glycoproteins acting as adhesion molecules involved in the development of different inflammatory reactions. Various eye, skin and lung diseases are associated with induction of soluble selectins. In this study serum levels of soluble forms of selectins (sL-selectin, sP-selectin and sE-selectin) were evaluated in the sulfur mustard (SM) exposed and the control groups using ELISA method. sL-selectin was significantly lower in the SM exposed group compared to the control group (1131.5+/-16.3 and 1205.7+/-26.9 pg/ml respectively; p=0.021). The serum levels of sP-Selectin was significantly reduced in the SM exposed group in comparison to the control group (149.35+/-2.61 and 170.25+/-5.16 pg/ml respectively; p<0.001). sE-selectin was significantly increased in sera of the exposed group compared to the control group (29.64+/-0.902 and 24.61+/-1.26 pg/ml respectively; p=0.003). sL-selectin positively correlated with the percentage of polymorphonuclear cells and negatively with the percentage of lymphocytes. There was a significant correlation between the count of platelets and sP-selectin in both the control and exposed groups. The change in the pattern of selectins in the SM exposed group in comparison to the control group may indicate suppressed acute inflammatory condition in which new remodeling of cytokine expression play a more crucial role in the immune-regulation.