Detection of gut and mucosal peptides through TOMAHAQ in healthy individuals.
Detection of gut and mucosal peptides through TOMAHAQ in healthy individuals.
复制标题
通过 TOMAHAQ 检测健康个体的肠道和粘膜肽。
作者：
Parsons,ES;Liu,F;Kaushik,A;Lee,A;Schuetz,J;Dunham,D;Seastedt,H;Ogulur,I;Heider,A;Tan,G;Shah,A;Cao,S;Smith,E;Kost,L;Acharya,S;Prunicki,M;Rothenberg,M;Sindher,S;Leib,R;Akdis,CA;Nadeau,K;Lejeune,S
对于编辑来说，皮肤屏障以及如何跟踪其渗透性的潜在缺陷一直是最近感兴趣的话题。我们假设，在皮肤、肺、肠道细胞和分泌组织中合成的某些细菌肽和蛋白质的肽片段不应该迁移到身体的其他部分，除非存在屏障缺陷。因此，血浆中存在来自胃肠道的多肽表明个体各自的肠道屏障存在功能缺陷。上皮屏障假说认为，环境暴露和/或遗传风险因素对皮肤或粘膜的损害可能会导致残留的炎症，因为微生物区系可能移位到亚上皮细胞，这与多种自身免疫状况和变态反应性疾病有关。1本实验的目的是利用靶向质谱仪对健康个体进行探索性分析，以测试是否可以在血浆中检测到肠道和粘膜多肽，作为潜在的生物标志物，表明存在屏障缺陷和粘膜渗漏。使用有针对性的方法，从文献中选择了115个肽(有关进一步的方法，请参阅在线补充资料)。55个常规检测的多肽的子集使用触发偏移、多路复用、准确质量、高分辨率和绝对定量(TOMAHAQ)进行定量(有关更多方法，请参阅在线补充资料)。2所分析的多肽的完整清单包括在表S2中。通过网络分析对32名参与者(1-22岁)的数据进行了分析(进一步的人口统计数据见表S1)。进行网络分析以可视化和鉴定生物相关的多肽，并检查已知的生物相互作用。55个多肽中有31个具有显著的相关性，具有高度的确定性；多肽之间的联系由Spearman相关系数大于0.75和p值>；0.01来定义(图1A)。最相互关联的前10个多肽都是相互正相关的(图1B)。为了进一步验证这些多肽是否高度相互关联，使用了k-均值聚类，并保留了相同的31个多肽。细菌肽(QPVDEIVEYGPTK)是相互连接度最高的多肽(S3)。QPVDEIVEYGPTK是一种来源于表皮葡萄球菌聚集相关蛋白(AAP)的胰蛋白酶多肽，与其他细菌没有相同的同源性。随着QPVDEIVEYGPTK数量的增加，所有其他多肽的水平也增加，如图1A所示。QPVDEIVEYGPTK与胃肠肽AHVAFPDFFR呈正相关，AHVAFPDFFR是蔗糖酶异构酶的一种胰解肽(q=0.0041)，以前曾与肠道屏障缺陷有关(图2A)。3此外，QPVDEIVEYGPTK与来源于带蛋白和结合珠蛋白的血浆蛋白多肽VQRILGGHLDAK(q=3×10−19)呈正相关。佐林以前也与肠道通透性有关(图2B)。4此外，AHVAFPDFFR(p=0.00287)和VQRILGGHLDAK(p=3.52×10−06)都与检测到的细菌肽总数呈显著正相关。QPVDEIVEYGPTK与IL-33多肽DESYEIYVEDLK呈正相关(p=1.64*10−05)，提示与上皮细胞的警报反应有关(图2B)。这些结果表明，血浆中QPVDEIVEYGPTK水平随着肠道和粘膜多肽的增加而增加，提示来自S和…的AAP多肽增加了肠道通透性
To the Editor, The skin barrier and how to track potential defects in its permeability has been a topic of recent interest. We hypothesized that certain bacterial peptides and peptide fragments of proteins synthetized in skin, lung, and gut cells and secretary tissues draining to the gut should not migrate to other compartments of the body unless a barrier defect is present. Therefore, the presence of peptides from the gastrointestinal tract in blood plasma suggests a functional defect in an individual's respective gut barrier. The epithelial barrier hypothesis suggests that damage to the skin or mucosa via environmental exposures and/or genetic risk factors can result in residual inflammation due to possible translocation of microbiota to the sub-epithelium, which is associated with multiple autoimmune conditions and allergic disorders. 1 The intent of this experiment was to conduct exploratory analysis using targeted mass spectrometry on healthy individuals to test whether gut and mucosal peptides can be detected in plasma, as potential biomarkers which indicate the presence of barrier defects and mucosal leakiness. Using a targeted approach, 115 peptides were selected from the literature (see online supplement for further methods). A subset of 55 regularly detected peptides were quantified using Triggered by Offset, Multiplexed, Accurate mass, High resolution, and Absolute Quantitation (TOMAHAQ)(see online supplement for further methods). 2 A complete list of peptides analyzed is included in Table S2. Data were analyzed from 32 participants (1–22 years) via network analysis (further demographic data is provided in Table S1). Network analysis was conducted to visualize and identify biologically relevant peptides and check for known biological interactions. Thirty-one out of 55 peptides were significantly intercorrelated with high degree of certainty; connections between peptides were defined by a Spearman's correlation coefficient greater than 0.75 and a p-value of> 0.01 (Figure 1A). The top 10 most interconnected peptides were all positively associated with one another (Figure 1B). To further validate, if these peptides were highly interconnected, k-means clustering was applied and the same 31 peptides were conserved. A bacterial peptide (QPVDEIVEYGPTK) was the most interconnected peptide and had the highest degree of connections (S3). QPVDEIVEYGPTK is tryptic peptide from the accumulation-associated protein (AAP) from Staphylococcus epidermidis with no shared homologies with other bacteria. As quantities of QPVDEIVEYGPTK increased so did levels of all other peptides pictured in Figure 1A. QPVDEIVEYGPTK was positively associated with the gastro-intestinal peptide AHVAFPDFFR, a tryptic peptide from sucrase isomaltase (q= 0.0041), which has been previously associated with gut barrier defects (Figure 2A). 3 Additionally, QPVDEIVEYGPTK was positively associated with the plasma protein peptide VQRILGGHLDAK (q= 3* 10− 19) which is derived from both zonulin and haptoglobin. Zonulin has been previously associated with gut permeability as well (Figure 2B). 4 Furthermore, both AHVAFPDFFR (p= 0.00287) and VQRILGGHLDAK (p= 3.52* 10− 06) had positive significant associations with the total number of bacterial peptides detected. QPVDEIVEYGPTK was positively associated with the presence of an IL-33 peptide, DESYEIYVEDLK (p= 1.64* 10− 05), suggesting an association with the alarmin response from the epithelia (Figure 2B). These findings indicate that as levels of QPVDEIVEYGPTK increased in plasma along with gut and mucosal peptides, suggesting that gut permeability increases with peptides from AAP from S …