树突状细胞上的 β2 整合素调节细胞因子信号和炎症相关基因表达,并对诱导自身免疫性脑脊髓炎至关重要。
β2 Integrins on Dendritic Cells Modulate Cytokine Signaling and Inflammation-Associated Gene Expression, and Are Required for Induction of Autoimmune Encephalomyelitis.
机构信息
Department of Dermatology, University Medical Center, Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany.
Institute for Molecular Medicine, University Medical Center, Johannes Gutenberg University of Mainz, Langenbeckstraße 1, 55131 Mainz, Germany.
出版信息
Cells. 2022 Jul 13;11(14):2188. doi: 10.3390/cells11142188.
Heterodimeric β2 integrin surface receptors (CD11a-d/CD18) are specifically expressed by leukocytes that contribute to pathogen uptake, cell migration, immunological synapse formation and cell signaling. In humans, the loss of CD18 expression results in leukocyte adhesion deficiency syndrome (LAD-)1, largely characterized by recurrent severe infections. All available mouse models display the constitutive and ubiquitous knockout of either α or the common β2 (CD18) subunit, which hampers the analysis of the cell type-specific role of β2 integrins in vivo. To overcome this limitation, we generated a CD18 gene floxed mouse strain. Offspring generated from crossing with CD11c-Cre mice displayed the efficient knockdown of β2 integrins, specifically in dendritic cells (DCs). Stimulated β2-integrin-deficient splenic DCs showed enhanced cytokine production and the concomitantly elevated activity of signal transducers and activators of transcription (STAT) 1, 3 and 5, as well as the impaired expression of suppressor of cytokine signaling (SOCS) 2-6 as assessed in bone marrow-derived (BM) DCs. Paradoxically, these BMDCs also showed the attenuated expression of genes involved in inflammatory signaling. In line, in experimental autoimmune encephalomyelitis mice with a conditional DC-specific β2 integrin knockdown presented with a delayed onset and milder course of disease, associated with lower frequencies of T helper cell populations (Th)1/Th17 in the inflamed spinal cord. Altogether, our mouse model may prove to be a valuable tool to study the leukocyte-specific functions of β2 integrins in vivo.
异源二聚体 β2 整合素表面受体(CD11a-d/CD18)特异性表达于白细胞,有助于病原体摄取、细胞迁移、免疫突触形成和细胞信号转导。在人类中,CD18 表达的缺失导致白细胞黏附缺陷综合征(LAD-)1,其主要特征是反复发生严重感染。所有现有的小鼠模型均显示出 α 或共同的 β2(CD18)亚基的组成型和普遍敲除,这阻碍了体内β2 整合素在细胞类型特异性中的作用分析。为了克服这一限制,我们构建了 CD18 基因 floxed 小鼠品系。与 CD11c-Cre 小鼠杂交的后代显示出 β2 整合素的有效敲低,特别是在树突状细胞(DC)中。刺激的β2 整合素缺陷脾 DC 显示细胞因子产生增强,同时信号转导和转录激活物(STAT)1、3 和 5 的活性升高,以及骨髓来源的(BM)DC 中抑制细胞因子信号(SOCS)2-6 的表达受损。矛盾的是,这些 BMDC 也显示出参与炎症信号的基因表达减弱。与此一致,在条件性 DC 特异性β2 整合素敲低的实验性自身免疫性脑脊髓炎小鼠中,疾病的发病和严重程度延迟,与炎症性脊髓中 Th1/Th17 T 辅助细胞群的频率降低相关。总之,我们的小鼠模型可能成为研究体内β2 整合素在白细胞中的特异性功能的有用工具。