Infectious Diseases and Immunopathogenesis Research Group, Discipline of Microbiology and Immunology, James Cook University, Townsville, Queensland, Australia.
Infect Immun. 2012 Jun;80(6):2089-99. doi: 10.1128/IAI.00212-12. Epub 2012 Apr 2.
Melioidosis is a potentially fatal disease caused by the bacterium Burkholderia pseudomallei. Type 2 diabetes (T2D) is the most common comorbidity associated with melioidosis. B. pseudomallei isolates from melioidosis patients with T2D are less virulent in animal models than those from patients with melioidosis and no identifiable risk factors. We developed an ex vivo whole-blood assay as a tool for comparison of early inflammatory profiles generated by T2D and nondiabetic (ND) individuals in response to a B. pseudomallei strain of low virulence. Peripheral blood from individuals with T2D, with either poorly controlled glycemia (PC-T2D [n = 6]) or well-controlled glycemia (WC-T2D [n = 8]), and healthy ND (n = 13) individuals was stimulated with B. pseudomallei. Oxidative burst, myeloperoxidase (MPO) release, expression of pathogen recognition receptors (TLR2, TLR4, and CD14), and activation markers (CD11b and HLA-DR) were measured on polymorphonuclear (PMN) leukocytes and monocytes. Concentrations of plasma inflammatory cytokine (interleukin-6 [IL-6], IL-12p70, tumor necrosis factor alpha [TNF-α], monocyte chemoattractant protein 1 [MCP-1], IL-8, IL-1β, and IL-10) were also determined. Following stimulation, oxidative burst and MPO levels were significantly elevated in blood from PC-T2D subjects compared to controls. Differences were also observed in expression of Toll-like receptor 2 (TLR2), CD14, and CD11b on phagocytes from T2D and ND individuals. Levels of IL-12p70, MCP-1, and IL-8 were significantly elevated in blood from PC-T2D subjects compared to ND individuals. Notably, differential inflammatory responses of PC-T2D, WC-T2D, and ND individuals to B. pseudomallei occur independently of bacterial load and confirm the efficacy of this model of T2D-melioidosis comorbidity as a tool for investigation of dysregulated PMN and monocyte responses to B. pseudomallei underlying susceptibility of T2D individuals to melioidosis.
类鼻疽是由伯克霍尔德菌引起的一种潜在致命疾病。2 型糖尿病（T2D）是与类鼻疽相关的最常见合并症。与无明确危险因素的类鼻疽患者相比，来自 T2D 类鼻疽患者的 B. pseudomallei 分离株在动物模型中的毒力较低。我们开发了一种体外全血测定法，作为比较 T2D 和非糖尿病（ND）个体对低毒力 B. pseudomallei 菌株产生的早期炎症谱的工具。来自血糖控制不佳（PC-T2D [n = 6]）或血糖控制良好（WC-T2D [n = 8]）的 T2D 个体以及健康 ND（n = 13）个体的外周血用 B. pseudomallei 刺激。在多形核（PMN）白细胞和单核细胞上测量氧化爆发、髓过氧化物酶（MPO）释放、病原体识别受体（TLR2、TLR4 和 CD14）和激活标志物（CD11b 和 HLA-DR）的表达。还测定了血浆炎症细胞因子（白细胞介素 6 [IL-6]、IL-12p70、肿瘤坏死因子-α[TNF-α]、单核细胞趋化蛋白 1 [MCP-1]、IL-8、IL-1β和 IL-10）的浓度。刺激后，与对照组相比，PC-T2D 受试者的血液中氧化爆发和 MPO 水平显着升高。T2D 和 ND 个体的吞噬细胞中 Toll 样受体 2（TLR2）、CD14 和 CD11b 的表达也存在差异。与 ND 个体相比，PC-T2D 受试者血液中的 IL-12p70、MCP-1 和 IL-8 水平显着升高。值得注意的是，PC-T2D、WC-T2D 和 ND 个体对 B. pseudomallei 的炎症反应差异独立于细菌负荷，并证实了这种 T2D-类鼻疽合并症模型作为研究 T2D 个体对类鼻疽易感性的 PMN 和单核细胞对 B. pseudomallei 反应失调的工具的有效性。
