Peter Wills Bioinformatics Centre, Darlinghurst, Australia.
Cell Transplant. 2012;21(9):2063-78. doi: 10.3727/096368911X627372. Epub 2012 Mar 8.
In the context of islet transplantation, experimental models show that induction of islet intrinsic NF-κB-dependent proinflammatory genes can contribute to islet graft rejection. Isolation of human islets triggers activation of the NF-κB and mitogen-activated kinase (MAPK) stress response pathways. However, the downstream NF-κB target genes induced in human islets during the isolation process are poorly described. Therefore, in this study, using microarray, bioinformatic, and RTqPCR approaches, we determined the pattern of genes expressed by a set of 14 human islet preparations. We found that isolated human islets express a panel of genes reminiscent of cells undergoing a marked NF-κB-dependent proinflammatory response. Expressed genes included matrix metallopeptidase 1 (MMP1) and fibronectin 1 (FN1), factors involved in tissue remodeling, adhesion, and cell migration; inflammatory cytokines IL-1β and IL-8; genes regulating cell survival including A20 and ATF3; and notably high expression of a set of chemokines that would favor neutrophil and monocyte recruitment including CXCL2, CCL2, CXCL12, CXCL1, CXCL6, and CCL28. Of note, the inflammatory profile of isolated human islets was maintained after transplantation into RAG(-/-) recipients. Thus, human islets can provide a reservoir of NF-κB-dependent inflammatory factors that have the potential to contribute to the anti-islet-graft immune response. To test this hypothesis, we extracted rodent islets under optimal conditions, forced activation of NF-κB, and transplanted them into allogenic recipients. These NF-κB activated islets not only expressed the same chemokine profile observed in human islets but also struggled to maintain normoglycemia posttransplantation. Further, NF-κB-activated islets were rejected with a faster tempo as compared to non-NF-κB-activated rodent islets. Thus, isolated human islets can make cell autonomous contributions to the ensuing allograft response by elaborating inflammatory factors that contribute to their own demise. These data highlight the potential importance of islet intrinsic proinflammatory responses as targets for therapeutic intervention.
在胰岛移植的背景下，实验模型表明，诱导胰岛固有 NF-κB 依赖性促炎基因可能导致胰岛移植物排斥。人胰岛的分离会触发 NF-κB 和丝裂原活化蛋白激酶 (MAPK) 应激反应途径的激活。然而，在人胰岛分离过程中诱导的下游 NF-κB 靶基因描述较差。因此，在这项研究中，我们使用微阵列、生物信息学和 RTqPCR 方法，确定了一组 14 个人胰岛制剂表达的基因模式。我们发现，分离的人胰岛表达了一组类似于经历明显 NF-κB 依赖性促炎反应的细胞的基因。表达的基因包括基质金属蛋白酶 1 (MMP1) 和纤维连接蛋白 1 (FN1)，这些因子参与组织重塑、黏附和细胞迁移；炎症细胞因子 IL-1β 和 IL-8；调节细胞存活的基因包括 A20 和 ATF3；值得注意的是，一组趋化因子的高表达，这些趋化因子将有利于中性粒细胞和单核细胞的募集，包括 CXCL2、CCL2、CXCL12、CXCL1、CXCL6 和 CCL28。值得注意的是，移植到 RAG(-/-)受者体内后，分离的人胰岛的炎症特征得以维持。因此，人胰岛可以提供 NF-κB 依赖性炎症因子的储存库，这些因子有可能导致抗胰岛移植物免疫反应。为了验证这一假设，我们在最佳条件下提取啮齿动物胰岛，强制激活 NF-κB，并将其移植到同种异体受者体内。这些 NF-κB 激活的胰岛不仅表达了在人胰岛中观察到的相同趋化因子谱，而且在移植后难以维持正常血糖。此外，与非 NF-κB 激活的啮齿动物胰岛相比，NF-κB 激活的胰岛的排斥速度更快。因此，分离的人胰岛可以通过产生促炎因子来自主参与随后的同种异体反应，这些因子有助于其自身的消亡。这些数据强调了胰岛固有促炎反应作为治疗干预靶点的潜在重要性。
