Supplementary Material for: TNFAIP2 Inhibits Early TNFa-Induced NF-κB Signaling and Decreases Survival in Septic Shock Patients

During septic shock, tumor necrosis factor alpha (TNFa) is an early response gene and induces a plethora of genes and signaling pathways. To identify robust signals in genes reliably upregulated by TNFa, we first measured microarray gene expression in vitro and searched methodologically comparable, publicly available data sets to identify concordant signals. Using tag single-nucleotide polymorphisms in the genes common to all data sets, we identified a genetic variant of the <i>TNFAIP2</i> gene, rs8126, associated with decreased 28-day survival and increased organ dysfunction in an adult cohort in the Vasopressin and Septic Shock Trial. Similar to this cohort, we found that an association with rs8126 and increased organ dysfunction is replicated in a second cohort of septic shock patients in the St. Paul's Hospital Intensive Care Unit. We found that TNFAIP2 inhibits NF-κB activity, impacting the downstream cytokine interleukin (IL)-8. The minor G allele of TNFAIP2 rs8126 resulted in greater TNFAIP2 expression, decreased IL-8 production and was associated with decreased survival in patients experiencing septic shock. These data suggest that TNFAIP2 is a novel inhibitor of NF-κB that acts as an autoinhibitor of the TNFa response during septic shock.在脓毒性休克病程中，肿瘤坏死因子α（tumor necrosis factor alpha, TNFα）是一类早期应答基因，可诱导大量基因及信号通路的活化。为精准识别肿瘤坏死因子α（TNFα）可靠上调的基因中的稳健信号，我们首先在体外开展了基因芯片表达谱检测，并系统检索了方法学可比的公开数据集以筛选一致性信号。通过针对所有数据集共有基因设计的标签单核苷酸多态性（tag single-nucleotide polymorphisms），我们在《血管加压素与脓毒性休克试验》的成人队列中，发现<i>TNFAIP2</i>基因的rs8126遗传变异位点，该位点与患者28天生存率降低及器官功能障碍程度升高显著相关。与该队列结果一致，我们在圣保罗医院重症监护病房（St. Paul's Hospital Intensive Care Unit, ICU）的另一组脓毒性休克患者队列中，成功重复验证了rs8126与器官功能障碍程度升高的关联。研究发现，TNFAIP2可抑制核因子κB（NF-κB）的活性，进而影响下游细胞因子白细胞介素8（interleukin-8, IL-8）的产生。TNFAIP2 rs8126的次要等位基因G可导致TNFAIP2表达水平升高、IL-8产生减少，并与脓毒性休克患者的生存率降低显著相关。上述研究结果表明，TNFAIP2是一种新型核因子κB抑制因子，可在脓毒性休克病程中作为肿瘤坏死因子α（TNFα）应答的自抑制因子发挥作用。