Center of Experimental & Molecular Medicine, Amsterdam University Medical Centers, Location Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Amsterdam University Medical Centers, Location Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
Cells. 2022 Feb 24;11(5):787. doi: 10.3390/cells11050787.
DNA methyltransferase 3b (Dnmt3b) has been suggested to play a role in the host immune response during bacterial infection. Neutrophils and other myeloid cells are crucial for lung defense against infection. This study aimed to investigate the role of Dnmt3b in neutrophils and myeloid cells during acute pneumonia caused by . Neutrophil-specific () or myeloid cell-specific () Dnmt3b-deficient mice and littermate control mice were infected with PAK via the airways. Bacteria burdens, neutrophil recruitment, and activation (CD11b expression, myeloperoxidase, and elastase levels), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF) were measured in bronchoalveolar lavage fluid (BALF) at 6 and 24 h after infection. Our data showed that the bacterial loads and neutrophil recruitment and activation did not differ in BALF obtained from neutrophil-specific Dnmt3b-deficient and control mice, whilst BALF IL-6 and TNF levels were lower in the former group at 24 but not at 6 h after infection. None of the host response parameters measured differed between myeloid cell-specific Dnmt3b-deficient and control mice. In conclusion, dnmt3b deficiency in neutrophils or myeloid cells does not affect acute immune responses in the airways during pneumonia.
DNA 甲基转移酶 3b（Dnmt3b）被认为在细菌感染期间宿主免疫反应中发挥作用。中性粒细胞和其他髓样细胞对于肺部抗感染至关重要。本研究旨在研究 Dnmt3b 在 引起的急性肺炎中的中性粒细胞和髓样细胞中的作用。通过气道感染 PAK ，研究了中性粒细胞特异性（）或髓样细胞特异性（）Dnmt3b 缺陷小鼠和同窝对照小鼠。在感染后 6 和 24 小时，测量支气管肺泡灌洗液（BALF）中的细菌负荷、中性粒细胞募集和激活（CD11b 表达、髓过氧化物酶和弹性蛋白酶水平）、白细胞介素（IL）-1β、IL-6 和肿瘤坏死因子（TNF）。我们的数据表明，中性粒细胞特异性 Dnmt3b 缺陷和对照小鼠的 BALF 中细菌负荷和中性粒细胞募集和激活没有差异，而感染后 24 小时而非 6 小时前者的 BALF IL-6 和 TNF 水平较低。髓样细胞特异性 Dnmt3b 缺陷和对照小鼠之间测量的任何宿主反应参数均无差异。总之，中性粒细胞或髓样细胞中的 dnmt3b 缺陷不影响 肺炎期间气道中的急性免疫反应。
