Amelioration of Vesicant-Induced Skin Injury by High Dose 25-Hydroxyvitamin D

描述(申请人提供)：直接皮肤接触发泡剂，如氮芥末或氮芥末相关亚硝脲(BCNU(卡莫司汀))会产生剂量依赖的症状，这些症状在伤口愈合的开始、严重程度和持续时间上各不相同。虽然暴露在发泡剂本身会引起原发损伤(第一次打击)，但对皮肤的直接侮辱会导致激活的超炎性单核/巨噬细胞(M)延迟涌入，从而对皮肤构成额外的侮辱(第二次打击)，从而促进灾难性的皮肤损伤。然而，第一次和第二次组织命中之间的间隔代表了对抗机会。已有报道维生素D减弱M的激活，在临床轶事中证实了这一效果，我们最近治疗了一名患者，他在使用口服维生素D的BCNU局部治疗后表现出持续的皮肤毒性反应。这一成功使我们假设，用25(OH)D3减弱过度激活的M将是阻止皮肤破坏进展的有效对策，皮肤破坏是暴露于发泡剂后的一个关键发病因素。这里介绍的多学科转换方法利用了凯斯西部储备大学皮肤科和医学系和大学医院凯斯医疗中心强大的基础设施。人体临床试验样本以及小鼠体内和体外样本将被用来评估维生素D作为对抗亚硝脲和氮芥末暴露后M激活引起的皮肤损害的潜力。我们组织了一个国家专家小组，评估我们的进展情况，并帮助确定拟议工作的补充办法。使用从正在进行的烷化剂试验中获得的人类临床样本以及用机械氯乙胺治疗后获得的小鼠皮肤样本，我们建议评估：1)通过诱导可溶性信号分子TNFa和iNOS在BCNU暴露前和暴露后组织中M的渗透和激活水平。我们将再增加2个。)确定补充维生素D是否调节组织破坏，以及这是否通过M？激活的变化来调节。使用巨噬细胞限制性VDR基因敲除小鼠系统将证实M介导的反应的特异性。最后，我们将3。)开始一项维生素D干预试验，利用暴露于局部BCNU和氮芥末的患者，评估患者炎症生物标记物的变化、细胞浸润和患者体内高活性M的免疫组织化学染色，同时监测从基线到治疗后血清维生素D水平的变化。补充前和补充后收集的血清将用于在体外直接抑制自体巨噬细胞激活。这一战略的成功实施可能会在大规模暴露的情况下拯救生命，因为维生素D是安全的，而且可广泛获得。证明维生素D相关化合物可以防止发泡剂介导的组织破坏，这将导致对这一潜在治疗干预措施的高级评估。 与公共卫生相关：用作武器的化学发泡剂，如氮芥末或与氮芥末相关的亚硝脲(BCNU)，可对人类健康产生毁灭性影响。芥子是一种强大的烷化剂，上皮细胞，如角质形成细胞，暴露在这些试剂下，会导致氧化和亚硝化应激，最终导致细胞死亡。在皮肤中，这种细胞死亡表现为严重的皮肤起泡和脱屑。可以阻止这些化学物质影响的新疗法对治疗这些皮肤损伤将是无价的。这项建议同时使用小鼠和人类组织，解决了维生素D是否可以用作对抗因接触发泡剂而引发的过度激活的巨噬细胞的激活和随后的组织破坏。

DESCRIPTION (provided by applicant): Direct cutaneous exposure to vesicants such as nitrogen mustard or nitrogen mustard-related nitrosoureas (BCNU (carmustine)) produce dose-dependent symptoms that are varied in onset, severity and duration of wound healing. Although exposure to the vesicant itself evokes a primary injury (1st hit), the direct insult to the skin results in a delayed influx of activated hyper-inflammatory monocyte/macrophages (M) that constitute an additional insult to the skin (2nd hit) that promotes catastrophic skin injury. However, the interval between the first and second tissue hits represents a countermeasure opportunity. Attenuation of M activation by vitamin D has been reported, and in a clinical anecdotal confirmation of this effect, we have recently treated a patient who exhibited a persistent toxic skin response following topical BCNU treatment using oral vitamin D. This success leads us to hypothesize that attenuating hyper-activated M with 25(OH) D3 will be an effective countermeasure that halts progression of skin destruction, a key morbidity factor following exposure to vesicants. The multidisciplinary translational approach presented here that takes advantage of a strong infrastructure in the Departments of Dermatology and Medicine at Case Western Reserve University and University Hospitals Case Medical Center. Human clinical trial samples as well as murine in vivo and in vitro samples will be used assess the potential for vitamin D to act as a countermeasure to skin damage elicited by M activation following nitrosurea and nitrogen mustard exposure. We have organized a team of national experts to evaluate our progress and help identify complementary approaches to the proposed work. Using human clinical samples obtained from ongoing trials of alkylating agents as well as murine skin samples obtained post-treatment with mechlorethamine we propose to assess: 1.) The level of M infiltration and activation using induction of the soluble signaling molecules TNFa and iNOS in pre- and post-BCNU exposed tissue. We will further 2.) Determine whether vitamin D supplementation modulates tissue destruction and if this is mediated by changes in M¿ activation. Use of a macrophage-restricted VDR knockout mouse system will confirm the specificity of M mediated response. Finally, we will 3.) Begin a vitamin D interventional trial utilizing patients exposed to topical BCNU and nitrogen mustard to assess alteration of inflammatory biomarkers, cellular infiltration and immunohistochemical staining of hyper-activated M in patients while monitoring changes in serum vitamin D levels from baseline to post-therapy. Serum collected pre- and post- supplementation will be assayed for direct suppression of autologous macrophage activation in vitro. Successful implementation of this strategy is likely to save lives in the event of mass exposure as vitamin D is safe and widely available. Demonstration that vitamin D-related compounds protect against tissue destruction mediated by vesicants will lead to advanced evaluation of this potential therapeutic intervention. PUBLIC HEALTH RELEVANCE: Chemicals vesicants such as nitrogen mustard or nitrogen mustard-related nitrosureas (BCNU) used as weapons can have a devastating impact on human health. The mustards are powerful alkylating agents and exposure to these agents by epithelial cells, such as keratinocytes, result in induction of oxidative and nitrosative stress an eventual cell death. In the skin, this cell death manifests as severe skin blistering and desquamation. New therapeutics which can halt the effects of these chemicals will be invaluable to treating these skin injuries. Using both mouse and human tissue this proposal addresses whether vitamin D can be used as a counteragent to the activation and subsequent tissue destruction caused hyper-activated macrophages initiated through vesicant exposure.