Impact of Oral Disulfiram on Aldehyde Dehydrogenase (ALDH) Mediated Ocular Fibrosis in Mucous Membrane Pemphigoid (OcMMP)

结膜疤痕是由多种疾病引起的。其中包括沙眼，这是一种已知是全球可预防失明的最大原因的感染。在全球190万人中，它会导致不可逆转的双眼失明。在英国，最常见的原因是一种罕见的自身免疫驱动的疾病，称为眼粘膜类天疱疮(OcMMP)，每年每100万人口中就有0.8人发生这种疾病。OcMMP会造成结膜的慢性炎症和疤痕，结膜覆盖在眼皮内侧，覆盖在白色的眼睛上。眼皮内层的疤痕会导致睫毛向内翻转，擦伤角膜(倒睫)。这和炎症一起，导致持续的刺激、疼痛和干燥的衰弱症状。治疗包括免疫抑制，但这对疤痕形成几乎没有效果。对于一半的患者，疤痕形成仍在继续；20%成为不可逆转的失明。我们对OcMMP患者在接受诊断性结膜活检作为其常规临床护理的一部分，以及在我们的眼类天疱疮样小鼠模型中提取的结膜组织的研究表明，乙醛脱氢酶(ALDH)可以控制OcMMP人类组织和类天疱疮小鼠的结膜瘢痕形成。双硫兰(DSF；一种用于酒精滥用治疗的口服药片)永久性地阻断了ALDH的作用。我们发现DSF具有抗炎和抗瘢痕形成的特性，当给类天疱疮样小鼠滴眼液时(每天一次，连续一周)，DSF可以逆转炎症和瘢痕形成。我们想了解双硫仑是否有同样的作用机制，如果给予OcMMP患者。由于没有获得许可的双硫兰滴眼液配方，我们希望以英国许可的安全剂量口服片剂，给OCMPs患者为期两周，并检查它对结膜瘢痕信号的影响。我们将通过在开始治疗前、治疗一周后、治疗结束时和结束治疗后两周从患者身上采集拭子、泪液和血液样本来做到这一点。此前，我们已经从患有和不患有OcMMP的患者身上提取了结膜拭子，并证明了我们可以使用一种名为纳米线的技术在遗传水平上检测结膜瘢痕形成机制中的关键角色。纳米线使我们能够从一根棉签中检测到大量基因。我们已经确定了一组已知为瘢痕形成途径一部分的基因，这些基因在OcMMP患者的结膜中是异常的。重要的是，使用我们优化的一种灵敏的分析方法，我们已经能够量化泪液中的ALDH水平，并显示OCMPs患者的ALDH活性比那些没有患这种疾病的患者高出约10倍。这意味着我们可以测试给OcMMP患者服用双硫兰片是否会关闭结膜中的ALDH作用(使用泪液样本来确定)，以及这是否会改变疤痕形成过程(使用结膜拭子进行评估)。由于炎症会导致瘢痕形成，而且我们知道类天疱疮小鼠中的双硫兰滴眼液可以减少结膜炎症，我们将分析眼睛表面(使用泪水)和血液(使用血液样本)上是否存在炎症生物标记物，以确定服用双硫仑片是否也可以减少相关的炎症信号。通过这种方式，我们预计将产生足够的信息来支持我们的假设，即ALDH是人类结膜瘢痕形成途径的关键。由于应该避免不确定地使用口服双硫胺，这一发现将鼓励开发一种新的双硫兰抗瘢痕滴眼液，以在临床试验中进行治疗测试。我们的目标是改善OCMPs患者的生活体验，并通过减少这种疾病和其他结膜疤痕疾病的失明负担，在全球范围内改变患者护理。

Conjunctival scarring results from many diseases. These include trachoma, an infection that is known to be the largest cause of preventable blindness worldwide. It causes irreversible sight-loss in both eyes in 1.9 million worldwide. In the UK, the most common cause is a rare autoimmune driven disorder called Ocular Mucous Membrane Pemphigoid (OcMMP) that occurs in 0.8 people in a million population each year. OcMMP creates chronic inflammation and scarring of the conjunctiva which lines the inside of the eyelids and covers the white of the eye. Scarring of the inside lining of the eyelid can cause the lashes to turn inwards and scratch the cornea (trichiasis). This and inflammation, lead to debilitating symptoms of constant irritation, pain, and dryness. Treatments involve immunosuppression but this has little effect on scarring. For half of patients, scar formation continues; 20% become irreversibly blind.Our research on conjunctival tissue taken from patients with OcMMP whilst undergoing diagnostic conjunctival biopsies as part of their routine clinical care, and in our ocular pemphigoid-like mouse model, has shown that the enzyme, aldehyde dehydrogenase (ALDH), controls conjunctival scarring both in OcMMP human tissue and in the pemphigoid mouse. Disulfiram (DSF; a drug used as a tablet given by mouth for alcohol-abuse treatment) permanently blocks ALDH action. We have found that DSF has anti-inflammatory and anti-scarring properties and when given to the pemphigoid-like mouse in an eyedrop form (once daily for one week), DSF reverses inflammation and scarring.We would like to understand whether disulfiram has the same mechanism of action if given to patients with OcMMP. As there is no licensed disulfiram eyedrop formulation, we would like to give tablets by mouth at the UK licensed safe dose, to patients with OcMMP for two weeks and examine how it effects the scarring signals in the conjunctiva. We will do this by taking swabs, tear and blood samples from patients before starting treatment, one week into treatment, at the end of treatment and two weeks after coming off treatment. Previously, we have taken conjunctival swabs from patients with and without OcMMP and have shown that we can detect key players in the mechanisms of conjunctival scarring at a genetic level using a technique called nanostring. Nanostring allows us to detect a large number of genes from one swab. We have identified a cluster of genes known to be part of the scarring pathway that are abnormal in OcMMP patient conjunctiva. Importantly, using a sensitive assay optimised by us, we have been able to quantify ALDH levels in tears and have shown ALDH activity to be around 10 times higher in patients with OcMMP compared to those who do not have the disease. What this means is that we can test whether giving disulfiram tablets to patients with OcMMP switches off ALDH action in the conjunctiva (determined using tear samples) and whether this modifies the scarring process (assessed using conjunctival swabs). As inflammation drives scarring, and we know that the disulfiram eyedrop in the pemphigoid-like mouse reduced conjunctival inflammation, we will analyse the presence of inflammatory biomarkers both on the surface of the eye (using tears) and the bloodstream (using a blood sample) to see if taking disulfiram tablets can also reduce the associated inflammatory signals.In this way, we anticipate we will generate sufficient information to support our hypothesis that ALDH is pivotal to the human conjunctival scarring pathway. As indefinite use of oral disulfiram should be avoided, this finding will encourage development of a novel disulfiram anti-scarring eyedrop to test as a treatment in clinical trials. Our goal is to improve the patient experience of living with OcMMP, and to transform patient care on a global scale by reducing the burden of sight-loss for this and other conjunctival scarring disorders.