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61.
利用噬菌体杀灭巨噬细胞内耻垢分枝杆菌的实验研究   总被引:3,自引:0,他引:3  
目的探讨噬菌体能否杀灭巨噬细胞内耻垢分枝杆菌,并成为减少细胞内活菌量的手段。方法将体外培养的已感染耻垢分枝杆菌的小鼠腹腔巨噬细胞随机分为4组生理盐水组,噬菌体高剂量组、中剂量组和低剂量组。分别加入生理盐水0.1ml、10#噬菌体2.1×107噬菌斑形成单位(PFU)、2.1×106PFU和2.1×105PFU。通过洗涤去除细胞外的噬菌体与耻垢分枝杆菌,观察加入噬菌体24h后巨噬细胞内耻垢分枝杆菌活菌数量变化情况。并在电子显微镜下观察巨噬细胞吞噬噬菌体前后胞内改变情况。结果24h后生理盐水组巨噬细胞内活菌数的对数值为5.74±0.18,噬菌体高、中、低剂量组的活菌数对数值分别为4.77±0.08、4.97±0.17、5.33±0.13。生理盐水组的活菌数高于噬菌体高、中、低剂量组,其中生理盐水组与噬菌体高、中剂量组之间比较差异有统计学意义(P<0.01)。高、中剂量组间差异无统计学意义(P>0.05),高、低剂量组间差异有统计学意义(P<0.01)。电子显微镜显示噬菌体能感染细胞内的耻垢分枝杆菌,合成子代噬菌体。结论感染了分枝杆菌的巨噬细胞可以同时吞噬10#噬菌体,进入细胞内的噬菌体能感染裂解胞内分枝杆菌使活菌量减少,使噬菌体治疗分枝杆菌感染成为可能。  相似文献   
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The interactions between neurons, immune and immune-like glial cells can initiate the abnormal processes that underlie neuropathic pain. In the peripheral nervous system the resident macrophages may play an important role. In this study we investigated in experimental adult Sprague-Dawley rats how Iba-1 (ionized calcium binding adaptor molecule 1) (+) resident macrophages in the dorsal root ganglion (DRG) are activated after a spinal nerve ligation (SNL) or streptozotocin (STZ)-induced diabetes. The activation profile was defined by comparing the responses of resident macrophages against microglia in the spinal cord as they share a common origin. After SNL, the Iba-1 (+) macrophages in L5 DRG reached their activation peak 5 days later, clustered as satellite cells around large A-neurons, expressed the MHC-II marker, but did not show p-p38 and p-ERK1/2 activation and did not secrete IL-18. After STZ-induced diabetes, the Iba-1 (+) macrophages reached their activation peak 1 week later in L4 and L5 DRG, remained scattered between neurons, expressed the MHC-II marker only in L5 DRG, did not show p-p38 and p-ERK1/2 activation and did not secrete any of the investigated cytokines/chemokines. These responses suggest that depending on the type of lesion DRG Iba-1 (+) resident macrophages have different activation mechanisms, which are dissimilar to those in microglia.  相似文献   
64.
Macrophage function is not restricted to the innate and adaptive immune responses, but also includes host defence, wound healing, angiogenesis and homeostatic processes. Within the spectrum of macrophage activation there are two extremes: M1 classically activated macrophages which have a pro-inflammatory phenotype, and M2 alternatively activated macrophages which are pro-angiogenic and anti-inflammatory. An important property of macrophages is their plasticity to switch from one phenotype to the other and they can be defined in their polarisation state at any point between the two extremes. In order to determine what stage of activation macrophages are in, it is essential to profile various phenotypic markers for their identification. This review describes the angiogenic role for myeloid cells: circulating monocytes, Tie-2 expressing monocytes (TEMs), myeloid-derived suppressor cells (MDSCs), tumour associated macrophages (TAMs), and neutrophils. Each cell type is discussed by phenotype, roles within angiogenesis and possible targets as a cell therapy. In addition, we also refer to our own research on myeloid angiogenic cells (MACs), outlining their ability to induce angiogenesis and their similarities to alternatively activated M2 macrophages. MACs significantly contribute to vascular repair through paracrine mechanisms as they lack the capacity to differentiate into endothelial cells. Since MACs also retain plasticity, phenotypic changes can occur according to disease states and the surrounding microenvironment. This pro-angiogenic potential of MACs could be harnessed as a novel cellular therapy for the treatment of ischaemic diseases, such as diabetic retinopathy, hind limb ischaemia and myocardial infarction; however, caution needs to be taken when MACs are delivered into an inflammatory milieu.  相似文献   
65.
Cordyceps sinensis is a fungus that has been used for over 2,000 years in China as a treatment for a variety of conditions including infectious diseases. The available evidence suggests a hypothesis that any efficacy of C. sinensis as an anti-infective therapeutic would be related to a role as an activator of innate immune responses. The objectives of this study were first to investigate the ability of C. sinensis to activate pro-inflammatory responses in macrophages in vitro and induce protective responses against intracellular pathogens in vivo, and second to characterize a method of action. We found that C. sinensis activates murine macrophages to produce a variety of pro-inflammatory cytokines. IFN-γ synergizes with C. sinensis to amplify this response. Bacterial endotoxin contamination was ruled out as a potential artefact. The evidence presented in this study supports a hypothesis that C. sinensis activates macrophages by engaging Toll-like receptors and inducing mitogen-activated protein kinase (MAPK) pathways characteristic of inflammatory stimuli.  相似文献   
66.
The effects of synthetic analogue of peptide hormone thymulin, which is normally produced by thymic epithelial cells, on immune cells activity and blood cytokine profile had been studied in male NMRI mice with acute inflammation induced by injection of lipopolysaccharide from gram-negative bacteria (LPS, 250 μg/100 g of body weight). Inflammation induced by LPS resulted in accumulation of several plasma pro-inflammatory cytokines, IL-1β, IL-2, IL-6, TNF-α, interferon-γ, and also IL-10, anti-inflammatory cytokine. Thymulin previously injected in dose of 15 μg/100 g body weight, prevented the accumulation of proinflammatory cytokines in plasma. Thymulin also prevented LPS-induced up-regulation of production of several cytokines by spleen lymphocytes and peritoneal macrophages. Added in vitro, thymulin decreased the peak of TNF-α production in macrophages cultivated with LPS. In addition, thymulin lowered the peak of Hsp70 production induced by LPS treatment. The results indicate that thymulin having significant anti-inflammatory effect may be promising in clinical application.  相似文献   
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《Human immunology》2021,82(9):634-639
The monocyte/macrophage lineage cells were found involved in the pathogenesis of systemic sclerosis (SSc) disease. The naïve macrophages are activated either to M1 cells with proinflammatory roles or to M2 cells that function to resolve inflammation with tissue repair. Recently, cells with dual phenotypes were detected in SSc disease. So, we aimed in this study to demonstrate different monocyte/macrophage phenotypes in peripheral cells from a group of Egyptian SSc patients, correlating percentages of these cells with the clinical findings in patients.The study participants comprised 41 patients with diffuse cutaneous SSc disease and 25 healthy individuals as controls. Clinical, radiological, and laboratory tests were conducted for SSc patients. Different phenotypes of the monocyte/macrophage subsets were identified in peripheral blood of patients and controls by flow cytometry for characteristic M1 (CD80, CD86, and TLR4) and M2 (CD204, CD163 and CD206) markers.SSc patients showed higher percentages of peripheral cells of the M1, M2, and mixed M1/M2 phenotypes within the monocyte/macrophage lineage compared to controls. Different cell phenotypes were associated significantly with the disease duration, modified Rodnan’s score, the Medsger skin score, and the Medsger lung in SSc patients. Some cells with the M1/M2 phenotypes were higher in SSc patients with pitting scars, arthritis, and myalgia.  相似文献   
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目的 发热伴血小板减少综合征病毒(SFTSV)是新发传染病发热伴血小板减少综合征的致病病原,为布尼亚病毒科白蛉病毒属一种新型病毒.通过研究发热伴血小板减少综合征病毒在巨噬细胞中的亚细胞定位,了解SFTSV在细胞内的复制组装机制.方法 应用两种人源巨噬细胞系THP-1细胞和U937细胞,通过免疫荧光共聚焦方法分析SFTSV感染巨噬细胞后与高尔基体和内质网的共定位.结果 SFTSV可特异性感染巨噬细胞,在SFTSV感染的巨噬细胞中SFTSV核蛋白与高尔基体共定位于核周,与内质网紧密相邻,但没有共定位.结论 在SFTSV感染的巨噬细胞中,内质网和高尔基体可能是病毒进行加工修饰及包装成熟的重要场所.  相似文献   
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