■多杆菌型麻风病患者可发生急性炎症反应性发作,称为结节性麻风红斑(ENL),其特征是出现疼痛的皮肤结节和全身症状。中性粒细胞已被认为在ENL的发病机制中发挥作用,最近的全球转录组学分析显示中性粒细胞相关过程是ENL皮肤病变的特征。
■在这项研究中,我们将这个分析扩展到血液室,比较诊断时非反应性麻风病患者的全血转录组学(LL,n=7)和服用抗反应治疗前的ENL患者(ENL,n=15)。此外,对诊断时和沙利度胺治疗7天后出现ENL发作的患者进行了一项随访研究(THAL,n=10)。通过RT-qPCR在独立队列(ENL=8;LL=7)中进行验证。
■在ENL组中观察到中性粒细胞活化和脱颗粒相关基因的富集,与LL组中的表达相比,中性粒细胞活化标志物CD177的基因是ENL发作中最富集的基因。还观察到更多的促炎转录组,与先天免疫相关的基因表达增加。独立队列中的验证表明S100A8表达可以区分ENL和LL。与未处理的细胞水平相比,用麻风分枝杆菌超声体外刺激的血细胞上清液显示出更高的CD177水平,表明麻风杆菌可以激活表达CD177的中性粒细胞。值得注意的是,与轻度发作和LL患者相比,重度/中度ENL发作患者的血清中CD177蛋白水平提示较高,强调CD177是ENL严重程度的潜在系统性标志物,值得未来确认。此外,在ENL诊断时和沙利度胺治疗7天后对患者进行了一项随访研究(THAL,n=10)。在接受治疗的患者的转录组学特征中,中性粒细胞通路的富集是持续的;然而,重要的免疫靶标可能与沙利度胺在全身水平上的作用有关,特别是NLRP6和IL5RA,被揭露。
■总而言之,我们的研究加强了中性粒细胞在ENL发病机制中的关键作用,并揭示了可能使麻风病患者受益的潜在诊断候选物和新的治疗靶点.
UNASSIGNED: Patients with the multibacillary form of leprosy can develop reactional episodes of acute inflammation, known as erythema nodosum leprosum (ENL), which are characterized by the appearance of painful cutaneous nodules and systemic symptoms. Neutrophils have been recognized to play a role in the pathogenesis of ENL, and recent global transcriptomic analysis revealed neutrophil-related processes as a signature of ENL skin lesions.
UNASSIGNED: In this study, we expanded this analysis to the blood compartment, comparing whole blood transcriptomics of patients with non-reactional lepromatous leprosy at diagnosis (LL, n=7) and patients with ENL before administration of anti-reactional treatment (ENL, n=15). Furthermore, a follow-up study was performed with patients experiencing an ENL episode at the time of diagnosis and after 7 days of thalidomide treatment (THAL, n=10). Validation in an independent cohort (ENL=8; LL=7) was performed by RT-qPCR.
UNASSIGNED: An enrichment of neutrophil activation and degranulation-related genes was observed in the ENL group, with the gene for the neutrophil activation marker CD177 being the most enriched gene of ENL episode when compared to its expression in the LL group. A more pro-inflammatory transcriptome was also observed, with increased expression of genes related to innate immunity. Validation in an independent cohort indicated that S100A8 expression could discriminate ENL from LL. Supernatants of blood cells stimulated in vitro with Mycobacterium leprae sonicate showed higher levels of CD177 compared to the level of untreated cells, indicating that the leprosy bacillus can activate neutrophils expressing CD177. Of note, suggestive higher CD177 protein levels were found in the sera of patients with severe/moderate ENL episodes when compared with patients with mild episodes and LL patients, highlighting CD177 as a potential systemic marker of ENL severity that deserves future confirmation. Furthermore, a follow-up study was performed with patients at the time of ENL diagnosis and after 7 days of thalidomide treatment (THAL, n=10). Enrichment of neutrophil pathways was sustained in the transcriptomic profile of patients undergoing treatment; however, important immune targets that might be relevant to the effect of thalidomide at a systemic level, particularly NLRP6 and IL5RA, were revealed.
UNASSIGNED: In conclusion, our study reinforces the key role played by neutrophils in ENL pathogenesis and shed lights on potential diagnostic candidates and novel therapeutic targets that could benefit patients with leprosy.