Radiation and Chemical Program Research for Multi-Utility and Repurposed Countermeasures: A US Department of Health and Human Services Agencies Perspective

Although chemical and radiological agents cause toxicity through different mechanisms, the multiorgan injuries caused by these threats share similarities that convene on the level of basic biological responses. This publication will discuss these areas of convergence and explore "multi-utility" approaches that could be leveraged to address common injury mechanisms underlying actions of chemical and radiological agents in a threat-agnostic manner. In addition, we will provide an overview of the current state of radiological and chemical threat research, discuss the US Government's efforts toward medical preparedness, and identify potential areas for collaboration geared toward enhancing preparedness and response against radiological and chemical threats. We also will discuss previous regulatory experience to provide insight on how to navigate regulatory paths for US Food and Drug Administration (FDA) approval/licensure/clearance for products addressing chemical or radiological/nuclear threats. This publication follows a 2022 trans-agency meeting titled, "Overlapping Science in Radiation and Sulfur Mustard Exposures of Skin and Lung: Consideration of Models, Mechanisms, Organ Systems, and Medical Countermeasures," sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), a part of the National Institutes of Health (NIH). Discussions from this meeting explored the overlapping nature of radiation and chemical injury and spurred increased interest in how preparedness for one threat leads to preparedness for the other. Herein, subject matter experts from the NIAID and the Biomedical Advanced Research and Development Authority (BARDA), a part of the Administration for Strategic Preparedness and Response (ASPR), summarize the knowledge gained from recently funded biomedical research, as well as insights from the 2022 meeting. These topics include identification of common areas for collaboration, potential use of biomarkers of injury to identify injuries caused by both hazards, and common and widely available treatments that could treat damage caused by radiological or chemical threats.

Ophthalmic Complications and Managements of Sulfur Mustard Exposure: A Narrative Review

Sulfur mustard (SM) is a lethal chemical agent that affects many organs, particularly the eyes, respiratory system and skin. Even asymptomatic patients with documented SM vapor exposure may develop organ disorder many years later. Patients with even minor signs in the acute stage may experience late complications that necessitate surgery. Early decontamination and conservative measures could help the patients and decrease the complications. Despite decades of research, there is still no effective treatment for either acute or long-term SM-induced ocular complications. Even after multiple medications and surgical procedures, the majority of patients continue to have symptoms. For dry eye, punctual occlusion, autologous eye drops, and aggressive lubrication are used; for persistent epithelial defects (PED), tarsorrhaphy, amniotic membrane transplant, and stem cell transplantation are used; for total limbal stem cell deficiency (LSCD), living-related conjunctivolimbal allograft and keratolimbal allograft are used; for corneal vascularization, steroids, non-steroidal anti-inflammatory drugs, and anti-vascular endothelial growth factor prescribed; and for corneal opacities, corneal transplantation is done. Platelet rich plasma and topical drops containing stem cell transplantation for LSCD, photodynamic therapy paired with subconjunctival or topical anti-vascular endothelial growth factors for corneal vascularization, topical curcumin and topical ciclosporin-A for dry eye, and orbital fat-derived stem cells for PED are all alternative treatments that can be suggested. Despite the experimental and clinical research on the complications of SM exposure over the past decades, there is still no effective treatment for eye complications. However, supportive medical and surgical management has been applied with relatively good outcome.

A type IV collagenase inhibitor, N-hydroxy-3-phenyl-2-(4-phenylbenzenesulfonamido) propanamide (BiPS), suppresses skin injury induced by sulfur mustard

Sulfur mustard (SM) is a highly toxic blistering agent thought to mediate its action, in part, by activating matrix metalloproteinases (MMPs) in the skin and disrupting components of the basement membrane zone (BMZ). Type IV collagenases (MMP-9) degrade type IV collagen in the skin, a major component of the BMZ at the dermal-epidermal junction. In the present studies, a type IV collagenase inhibitor, N-hydroxy-3-phenyl-2-(4-phenylbenzenesulfonamido) propanamide (BiPS), was tested for its ability to protect the skin against injury induced by SM in the mouse ear vesicant model. SM induced inflammation, epidermal hyperplasia and microblistering at the dermal/epidermal junction of mouse ears 24-168 h post-exposure. This was associated with upregulation of MMP-9 mRNA and protein in the skin. Dual immunofluorescence labeling showed increases in MMP-9 in the epidermis and in the adjacent dermal matrix of the SM injured skin, as well as breakdown of type IV collagen in the basement membrane. Pretreatment of the skin with BiPS reduced signs of SM-induced cutaneous toxicity; expression of MMP-9 mRNA and protein was also downregulated in the skin by BiPS. Following BiPS pretreatment, type IV collagen appeared intact and was similar to control skin. These results demonstrate that inhibiting type IV collagenases in the skin improves basement membrane integrity after exposure to SM. BiPS may hold promise as a potential protective agent to mitigate SM induced skin injury.

Adipose-Derived Mesenchymal Stem Cells for Treatment of Airway Injuries in A Patient after Long-Term Exposure to Sulfur Mustard

OBJECTIVE

Sulfur mustard (SM) is a potent mutagenic agent that targets several organs, particularly lung tissue. Changes in morphological structure of the airway system are associated with chronic obstructive pulmonary deficiency following exposure to SM. Although numerous studies have demonstrated pathological effects of SM on respiratory organs, unfortunately there is no effective treatment to inhibit further respiratory injuries or induce repair in these patients. Due to the extensive progress and achievements in stem cell therapy, we have aimed to evaluate safety and potential efficacy of systemic mesenchymal stem cell (MSC) administration on a SM-exposed patient with chronic lung injuries.

MATERIALS AND METHODS

In this clinical trial study, our patient received 100×106cells every 20 days for 4 injections over a 2-month period. After each injection we evaluated the safety, pulmonary function tests (PFT), chronic obstructive pulmonary disease (COPD) Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), Borg Scale Dyspnea Assessment (BSDA), and 6 Minute Walk Test (6MWT). One-way ANOVA test was used in this study which was not significant (P>0.05).

RESULTS

There were no infusion toxicities or serious adverse events caused by MSC administration. Although there was no significant difference in PFTs, we found a significant improvement for 6MWT, as well as BSDA, SGRQ, and CAT scores after each injection.

CONCLUSION

Systemic MSC administration appears to be safe in SM-exposed patients with moderate to severe injuries and provides a basis for subsequent cell therapy investigations in other patients with this disorder (Registration Number: IRCT2015110524890N1).

Respiratory Complications Due to Sulfur Mustard Exposure

Sulfur mustard (SM) or bis (2-chloroethyl) sulfide is a vesicant and alkylating chemical weapon. SM was used in the 1980s against Iran by Iraqi forces. After exposure to SM in initial acute phase the greatest damage is incurred by the eyes, skin and lungs and the highest damage is caused to the lungs. This injury not only in the acute phase but also in the long-term has the highest prevalence among these patients. Clinical symptoms of people after exposure to SM start with irritation of the nose and sinuses in the mild doses to the runny nose and pain at higher doses and even irritation of the airways and bronchial engagement in very high doses. Respiratory complications in patients exposed to SM have been associated with long-term symptoms and these symptoms add to the intensity of the complication. Bloody sputum, feeling of tightness in the chest and shortness of breath over nights are among common symptoms; also the main respiratory symptoms including generalized wheezing, rale (crackle), decreased breath sounds and cyanosis and Apparently FEV1 is reduced by 50 mL/year. In these patients there are changes in blood cells especially in white blood cells and neutrophils and systemic inflammation and systemic changes with other comorbidities are observed. Although SM pulmonary patients' treatment is based on bronchodilators and long-acting-β2 agonists, paying attention to the comorbidities with prior systemic changes in these patients is a reason for the need to change treatment strategies of these patients with systemic and extra-pulmonary therapy.

Efficacy of Tiotropium Bromide and Rehabilitation Treatment on Pulmonary Function of Patients With Sulfur Mustard Lung Injury

Background:

Chronic pulmonary complication is the most common delayed toxic effect of sulfur mustard (SM) and it has no treatment so far.

Objectives:

To evaluate short-term therapeutic effects of inhaled tiotropium bromide and pulmonary rehabilitation on pulmonary function of patients with SM induced lung injury.

Patients and Methods:

In a randomized clinical trial, using convenient sampling method, 54 patients with chronic lung disease due to SM exposure were recruited in Baqiyatallah General Hospital, Tehran, Iran for a period of 2-month study. They were randomly divided into 3 groups of 18 participants each. Group 1 received routine drugs (Serevent, Flixotide), pulmonary rehabilitation 30 minutes/2 times a week, and tiotropium bromide 18 µg/day. Group 2 was treated with routine drugs and pulmonary rehabilitation and group 3 was only on the routine drugs. cardiopulmonary exercise test (CPET), plethysmographic measurements, and respiratory symptoms evaluation were performed before and after medical intervention.

Results:

In group 1, compared to group 3, significant differences were found with regard to symptoms of cough ([difference between the first and last visit in group 1: Diff 1] = -1.6, Diff 3 = -0.3, P = 0.01) and nocturnal dyspnea (Diff 1 = -1.9, Diff 3 = 0.0, P = 0.01), likewise, compared to group 2, significant differences were found with regard to lung function parameters of forced vital capacity (Diff 1 = 3.0, Diff 2 = -3.5, P = 0.03), forced expiratory volume in one second (Diff 1 = 3.9, Diff 2 = -5.6, P = 0.009), maximal mid-expiratory flow rate 25% - 75% (Diff 1 = 1.5, Diff 2 = -3.2, P = 0.007) and peak expiratory flow (Diff 1 = -2.06, Diff 2 = -4.3, P = 0.04). Total lung capacity (Diff 2 = 9.28, Diff 3 = -12.07, P = 0.02) and residual volume (Diff2 = 32.1, Diff3 = -27.6, P = 0.04) were increased in group 2 compared to group 3. There were no significant differences with regard to CPET results among all groups (P > 0.05).

Conclusions:

Inhalation of tiotropium bromide in combination with pulmonary rehabilitation could improve some plethysmographic lung volumes and clinical outcomes in patients with chronic pulmonary disease due to SM. Short-term prescription of pulmonary rehabilitation has no effect on CPET of patients.

Identification of Reliable Reference Genes for Quantification of MicroRNAs in Serum Samples of Sulfur Mustard-Exposed Veterans

Objective

In spite of accumulating information about pathological aspects of sulfur mustard (SM), the precise mechanism responsible for its effects is not well understood. Circulating microRNAs (miRNAs) are promising biomarkers for disease diagnosis and prognosis. Accurate normalization using appropriate reference genes, is a critical step in miRNA expression studies. In this study, we aimed to identify appropriate reference gene for microRNA quantification in serum samples of SM victims.

Materials and Methods

In this case and control experimental study, using quantitative real-time polymerase chain reaction (qRT-PCR), we evaluated the suitability of a panel of small RNAs including SNORD38B, SNORD49A, U6, 5S rRNA, miR-423-3p, miR-191, miR-16 and miR-103 in sera of 28 SM-exposed veterans of Iran-Iraq war (1980-1988) and 15 matched control volunteers. Different statistical algorithms including geNorm, Normfinder, best-keeper and comparative delta-quantification cycle (Cq) method were employed to find the least variable reference gene.

Results

miR-423-3p was identified as the most stably expressed reference gene, and miR- 103 and miR-16 ranked after that.

Conclusion

We demonstrate that non-miRNA reference genes have the least stabil- ity in serum samples and that some house-keeping miRNAs may be used as more reliable reference genes for miRNAs in serum. In addition, using the geometric mean of two reference genes could increase the reliability of the normalizers.

Teratogenic effects of sulfur mustard on mice fetuses

INTRODUCTION

Sulfur Mustard (SM) has been used as a chemical warfare agent, in the World War I and more recently during Iraq-Iran war in early 1980s'. Its biological poisoning effect could be local or systemic and its effect depends on environmental conditions, exposed organs, and the extent and duration of exposure. It is considered as a strong alkylating agent with known mutagenic, carcinogenic effects; although a few studies have been performed on its teratogenicity so far.

MATERIALS AND METHODS

Mice were administered with SM intraperitoneally with a dose of 0.75 and 1.5 mg/kg in different periods of their gestation (gestational age of 11, 13 and 14 weeks). Control mice groups were included. Between 5 and 9 mice were used in each group. Dams underwent cesarean section on day 19 of their gestation. External examination was performed on the animals investigating craniofacial and septal defects and limb malformations such as adactyly and syndactyly. All data were analyzed by Chi-Square test and Fisher's exact test. The P- value less than 0.05 was considered significant.

RESULTS

Craniofacial and septal defects as well as the limb malformations were the most common types of birth defects, displaying an extremely complex biomedical problem.

CONCLUSION

This study confirms a significant correlation between SM exposure and its teratogenic effect. We postulated that the malformations could be caused by an uncontrolled migration of neural crest cells, causing developmental disorders. In addition to environmental factors, modifying genes could play an important role in the pathogenesis of the defects.

Cleft Palate induced by Sulfur Mustard in mice fetus

Sulfur Mustard (SM) is a chemical warfare agent which was widely used in the World War I and more recently during Gulf war in the early 1980s'. SM is a strong alkylating agent with known mutagenic and carcinogenic effects; but only few studies have been published on its teratogenicity. Since SM has been widely used as a chemical weapon by the Iraqi regime against the Iranian soldiers as well as the civilian population particularly pregnant women in the border area; therefore, the investigation of SM adverse effects on cleft malformations which is one of the most frequent congenital anomalies is considered in this study. An experimental work has been carried out in embryopathy in mouse with intraperitoneal injection of 0.75 and 1.5 mg/kg SM at different periods of gestation. Cleft lip and palate were examined by stereomicroscopy. Current data demonstrate that exposure with SM on the 11th day of gestation can increase the incidence of cleft defects in comparison with control group (P<0.001). These results also show that SM treatment in GD 11 and 13 can lead to more anomalies compared with GD 14 (P<0.001). They also show that the teratogenic effects of SM are restrictively under the influence of the threshold dose and time of gestation. The present results suggest that exposure to sufficient doses of SM on critical days of gestation may increase the risk of congenital cleft malformations.

Prophylactic ophthalmic bethametazone for sulfur mustard-induced ocular injury

BACKGROUND

The present study sought to evaluate the prophylactic effect of bethametazone on sulfur mustard (SM)-induced ocular morphometric damage in the rabbit eye.

METHODS

Twenty five healthy New Zealand white rabbits were divided into 4 groups of normal (not exposed to SM or solution), solution (exposed to solution), SM (exposed to SM), and prophylactic bethametazone (received eye solution of bethametazone then exposed to SM solution; then treated for 2 weeks). On the day 14 after exposure, five-micron sections were stained with haematoxylin and eosin for light microscopy evaluation. The ocular morphometric characteristics in the study groups were compared to determine the prophylactic effects of the bethametazone.

RESULTS

Bethamethazone could protect eyes from SM effect by means of decrease in changes in number of Keratocyte in 10000 μm(2), thickness of cornea (μm), thickness of corneal epithelium (μm), number of meibomian gland's cells in 2500 μm(2), thickness of palpebral conjuctival epithelium (μm), thickness of epithelial of palpebral skin (μm), number of epithelial layers of palpebral skin, and number of goblet cells in conjunctival sac in 1000 μm.

CONCLUSIONS

Bethametazone may have a prophylactic effect on the early lesions of the eye of the rabbit due to SM exposure.

Are generic and disease-specific health related quality of life correlated? The case of chronic lung disease due to sulfur mustard

BACKGROUND

The aim of this study was to investigate the association between the two most commonly used generic and disease specific health-related quality of life (HRQoL) measures in patients with chronic lung disease due to SM: Medical Outcomes Study Short Form 36-Item (SF-36) and St George's Respiratory Questionnaire (SGRQ).

METHODS

This is a secondary analysis of Iranian Chemical Warfare Victims Health Assessment Study (ICWVHAS) during October 2007 in Isfahan, Iran. In that survey, conducted in an outpatient setting, 292 patients with chronic lung disease due to SM were selected from all provinces in Iran. The total score and sub scores of correlations of SGRQ and SF-36 were assessed. Correlation of quality-of-life scores were evaluated using Pearson's coefficient.

RESULTS

Samples were 276 patients who were selected for our analysis. No significant correlation was found between the total score or sub scores of SF-36 and the total score or sub scores of SGRQ (p > 0.05).

CONCLUSIONS

In patients with chronic lung disease due to SM, the SF-36 and SGRQ assess different aspects of HRQoL. Therefore applying both of them together, at least in the research setting is suggested.