BACKGROUND Colorectal surgery is associated with moderate-to-severe postoperative complications in over 25% of patients, predominantly infections. Monocyte epigenetic alterations leading to immune tolerance could explain postoperative increased susceptibility to infections. This research explores whether changes in monocyte DNA accessibility contribute to postoperative innate immune dysregulation. METHODS Damage-associated molecular patterns (DAMPs) and ex vivo cytokine production capacity were measured in a randomized controlled trial (n = 100) in colorectal surgery patients, with additional exploratory subgroup proteomic (proximity extension assay; Olink) and epigenomic analyses (Assay for Transposase-Accessible Chromatin [ATAC sequencing]). Monocytes of healthy volunteers were used to study the effect of high-mobility group box 1 (HMGB1) and heat shock protein 70 (HSP70) on cytokine production capacity in vitro. RESULTS Plasma DAMPs were increased after surgery. HMGB1 showed a mean 235% increase from before- (preop) to the end of surgery (95% confidence interval [CI] [166 - 305], P < .0001) and 90% increase (95% CI [63-118], P = .0004) preop to postoperative day 1 (POD1). HSP70 increased by a mean 12% from preop to the end of surgery (95% CI [3-21], not significant) and 30% to POD1 (95% CI [18-41], P < .0001). Nuclear deoxyribonucleic acid (nDNA) increases by 66% (95% CI [40-92], P < .0001) at the end of surgery and 94% on POD1 (95% CI [60-127], P < .0001). Mitochondrial DNA (mtDNA) increases by 370% at the end of surgery (95% CI [225-515], P < .0001) and by 503% on POD1 (95% CI [332-673], P < .0001). In vitro incubation of monocytes with HSP70 decreased cytokine production capacity of tumor necrosis factor (TNF) by 46% (95% CI [29-64], P < .0001), IL-6 by 22% (95% CI [12-32], P = .0004) and IL-10 by 19% (95% CI [12-26], P = .0015). In vitro incubation with HMGB1 decreased cytokine production capacity of TNF by 34% (95% CI [3-65], P = .0003), interleukin 1β (IL-1β) by 24% (95% CI [16-32], P < .0001), and IL-10 by 40% (95% CI [21-58], P = .0009). Analysis of the inflammatory proteome alongside epigenetic shifts in monocytes indicated significant changes in gene accessibility, particularly in inflammatory markers such as CXCL8 (IL-8), IL-6, and interferon-gamma (IFN-γ). A significant enrichment of interferon regulatory factors (IRFs) was found in loci exhibiting decreased accessibility, whereas enrichment of activating protein-1 (AP-1) family motifs was found in loci with increased accessibility. CONCLUSIONS These findings illuminate the complex epigenetic modulation influencing monocytes' response to surgical stress, shedding light on potential biomarkers for immune dysregulation. Our results advocate for further research into the role of anesthesia in these molecular pathways and the development of personalized interventions to mitigate immune dysfunction after surgery.

中文翻译：

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结直肠手术后先天免疫失调、蛋白质组学和单核细胞表观基因组学变化：一项随机对照试验的子研究。


背景 结直肠手术与超过 25% 的患者的中度至重度术后并发症有关，主要是感染。导致免疫耐受的单核细胞表观遗传改变可以解释术后对感染的易感性增加。本研究探讨了单核细胞 DNA 可及性的变化是否会导致术后先天免疫失调。方法 在结直肠手术患者的随机对照试验 （n = 100） 中测量损伤相关分子模式 （DAMPs） 和离体细胞因子产生能力，并额外进行探索性亚组蛋白质组学 （邻近延伸测定;Olink） 和表观基因组分析（转座酶可及染色质测定 [ATAC 测序]）。使用健康志愿者的单核细胞研究高迁移率组盒 1 （HMGB1） 和热休克蛋白 70 （HSP70） 对体外细胞因子产生能力的影响。结果 术后血浆 DAMP 增加。HMGB1 显示从术前（术前）到手术结束 （95% 置信区间 [CI] [166 - 305]，P < .0001） 和术前至术后第 1 天 （POD1） 平均增加 90% （95% CI [63-118]，P = .0004）。从术前到手术结束，HSP70平均增加了12%（95% CI [3-21]，无统计学意义），POD1平均增加了30%（95% CI [18-41]，P < .0001）。核脱氧核糖核酸 （nDNA） 在手术结束时增加了 66% （95% CI [40-92]，P < .0001），在 POD1 上增加了 94% （95% CI [60-127]，P < .0001）。线粒体DNA（mtDNA）在手术结束时增加370%（95% CI [225-515]，P < .0001），POD1增加503%（95% CI [332-673]，P < .0001）。单核细胞与 HSP70 的体外孵育使肿瘤坏死因子 （TNF） 的细胞因子产生能力降低了 46%（95% CI [29-64]，P <）。0001）、IL-6 降低 22% （95% CI [12-32]，P = .0004） 和 IL-10 降低 19% （95% CI [12-26]，P = .0015）。与HMGB1体外孵育后，TNF的细胞因子产生能力降低了34%（95% CI [3-65]，P=.0003），白细胞介素1β（IL-1β）降低了24%（95% CI [16-32]，P < .0001），IL-10的产生能力降低了40%（95% CI [21-58]，P=.0009）。对炎症蛋白质组以及单核细胞表观遗传变化的分析表明，基因可及性发生了显着变化，尤其是在 CXCL8 （IL-8）、IL-6 和干扰素-γ （IFN-γ 等炎症标志物中。在可及性降低的基因座中发现干扰素调节因子 （IRF） 的显著富集，而在可及性增加的基因座中发现激活蛋白-1 （AP-1） 家族基序的富集。结论这些发现阐明了影响单核细胞对手术应激反应的复杂表观遗传调控，揭示了免疫失调的潜在生物标志物。我们的结果主张进一步研究麻醉在这些分子途径中的作用，并开发个性化干预措施以减轻手术后的免疫功能障碍。