Eicosapentaenoic (EPA) and Docosahexaenoic (DHA) Acid Differentially Modulate Rat Neutrophil Function In Vitro

Fish oils are used as therapeutic agents in chronic inflammatory diseases. The omega-3 fatty acids (FA) found in these oils are mainly eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. The anti-inflammatory properties of fish oils are attributed to both omega-3 fatty acids. However, it is unknown whether such effects are due to either EPA or DHA. In this study, the effects of EPA and DHA on rat neutrophil function in vitro were compared. Both EPA and DHA increased the production of H₂O₂ when cells were stimulated or not with lipopolysaccharides (LPS). However, EPA was more potent than DHA in triggering an increase in superoxide release by cells in the basal condition or when stimulated with phorbol myristate acetate (PMA) or zymosan. Only DHA increased the phagocytic capacity and fungicidal activity of neutrophils. Both FA increased the release of tumor necrosis factor-α (TNF-α) in nonstimulated cells, but only EPA increased the production of cytokine-inducing neutrophil chemoattractant-2 (CINC-2) in the absence or presence of LPS, whereas production of interleukin-1 beta (IL-1β) was only increased by DHA in the presence of LPS. In addition, there was no alteration in the production of nitric oxide. In conclusion, we show herein that EPA and DHA can differently modulate aspects of the neutrophil response, which may be relevant for the development of therapies rich in one or other FA depending on the effect required.     

Particle-induced Phagocytic Cell Responses are Material Dependent: Foreign Body Giant Cells Vs. Osteoclasts from a Chick Chorioallantoic Membrane Particle-implantation Model

There is increasing concern about particles generated from wear-prone implants that are placed in body tissues, including artificial hip, knee, and jaw joints. Although phagocytes and foreign body giant cells are associated with inhaled or embedded particulate debris, some particles also induce bone digestion by eliciting the differentiation and proliferation of highly specialized osteoclastic cells. This report describes the differential phagocytic cellular responses to four implant-related types of ground, model wear particles in a live-egg cell-response model, as implants to the chick chorioallantoic membrane (CAM): polymethylmethacrylate (PMMA), a main constituent of some temporomandibular joint (TMJ) implants and orthopedic cements used to retain artificial hips and knees; Proplast-HA, an implantable composite of polytetrafluoroethylene (PTFE) and degradable mineral (hydroxyapatite) that has been associated with bone erosion around failed TMJ implants; talc, a nondegradable mineral sometimes found in tissues as a contaminant from talc-coated surgical gloves; and authentic bone, known to induce the formation of osteoclastic cells. Light and electron microscopy of CAM tissues harvested, sectioned and stained with special reagents for the enzymes tartrate-resistant acid phosphatase (TRAP) and tartrate-resistant adenosine triphosphatase (TrATPase), and for the osteoclast-specific antigen 121F, showed that only authentic bone and the degradable HA-rich particles induced osteoclast formation. From these results, and supporting data with polypropylene particles, it is concluded that nonbiodegradable polymer particles, alone, do not induce bone dissolution. Inert polymers do induce foreign body giant cells without the external mineral digestion qualities unique to osteoclasts, however. The chick embryo model system allows quick and affordable examination of material-dependent differences in phagocytic cellular responses to implant wear debris and particles from various occupational environments.     

比较两种墨汁注射途径对免疫低下小鼠廓清实验的影响

为研究不同墨汁注射部位对免疫低下小鼠廓清速率的影响，我们将昆明种小鼠分为生理盐水对照组和10、20、30mg／kg BW氢化可的松剂量组，并采取腹腔注射，隔日1次共3次的给药方法，于首次给药后第七天测定经内眦静脉丛和尾静脉注入墨汁后的碳廓清指数。结果显示：随氢化可的松剂量增加，2种给墨汁途径小鼠的校正吞噬指数随之降低，并呈现剂量一反应关系；2种给墨汁途径与其相应的对照组相比较，小鼠碳粒廓清能力在免疫正常与免疫低下状态时一致；进行廓清能力判定时，校正吞噬指数意义大于廓清指数。结论，内眦静脉法操作简单，以其测定免疫低下小鼠的廓清指数同样可以敏感地反映小鼠吞噬能力，建议推广使用。     

微波诱导小胶质细胞活化后吞噬功能及MFG-E8表达的变化

为探讨微波辐照致小胶质细胞活化后吞噬功能变化及其与MFG-E8表达的关系,采用60 mW/cm2的脉冲微波辐照N9小胶质细胞,ELISA技术测定TNF-α含量,硝酸还原酶法测定NO含量,免疫荧光检测CD11b和MFG-E8,Western blot检测MFG-E8蛋白表达。与正常对照组相比,辐照后3、12 h小胶质细胞中CD11b的表达明显增加(p<0.05),TNF-α和NO含量辐照后1 h即明显升高,并持续至辐照后24 h,小胶质细胞吞噬功能在辐照后3 h至6 h增强(p<0.05),12 h反而低于正常对照组(p<0.05),而MFG-E8蛋白表达与吞噬功能变化趋势相似。结果表明,60 mW/cm2的脉冲微波辐照可明显诱导小胶质细胞活化,活化后小胶质细胞对凋亡细胞的吞噬功能出现先增强后减弱的变化,而MFG-E8蛋白表达变化可能是其吞噬功能改变的主要原因之一。     

The Body's Response to Deliberate Implants: Phagocytic Cell Responses to Large Substrata Vs. Small Particles

It is important to characterize possible inflammatory responses to small particles, and to separate clearly these effects from responses to larger objects nearby. This research used a chemiluminescent assay, scanning electron micrographs, and energy dispersive X-ray spectra to monitor inflammation-related reactive oxygen intermediate (ROI) production and morphological alterations of human monocyte-derived macrophages interacting with the walls of apolar and polar polystyrene cuvettes, in the absence and presence of small particles of surface-characterized Teflon™, polyethylene, Co-Cr-Mo alloy, titanium and alumina. The two types of polystyrene substrata represent the “bacterial” (as produced) and “tissue culture” (gas-plasma-treated [GPT]) materials widely used in biological testing and tissue culture. Monocyte-derived macrophage spreading during contact with the higher-surface-energy, more polar substratum suppressed “oxidative bursts” to lower levels than expressed from rounded cells in contact with the lower-energy, apolar substratum. Particulate matter engulfed by both rounded and spread cells did not significantly enhance ROI production beyond levels observed for no-particle controls during the one-hour exposure time. Biocompatibility of some implants might be related to cell-spreading-induced suppression of ROI production, improving the tissue integration of GPT implants.     

毛蚶血细胞的形态观察及吞噬性能研究

以毛蚶为实验材料 ,利用细胞化学染色方法在光学显微镜下对毛蚶的血细胞进行观察。毛蚶的血细胞有四种组成 ,其中以红细胞为主 ,直径为 18.4± 0 .97μm ;透明细胞为 5 .6 3± 1.4 9μm ,核染色深 ,瑞氏染色胞质内光镜下未见颗粒 ;颗粒细胞胞质中含有着色颗粒 ,瑞氏染色后一种为桔红色 ,8± 1.0 6 μm ,另一种为兰色 ,6 .3± 1.2 5 μm ;另外还有极少量血细胞几乎没有细胞质 ,细胞大小为 5 .17± 1.6 9μm。分别在 4℃ ,10℃ ,2 0℃ ,30℃ ,37℃条件下研究毛蚶血细胞对白色念珠菌的体外吞噬实验。结果发现 ,颗粒细胞、透明细胞和红细胞都具有体外吞噬活性 ,以 30°C条件下吞噬百分率最高 ,达到 6 2 .11%。利用鳗弧菌Vibrioanguillirum对毛蚶进行免疫刺激后 ,毛蚶血细胞的吞噬能力与对照组相比明显增加     

Microglia-precursor cell interactions in health and in pathology

Until recently, microglia were mainly known as the resident phagocytes of the brain, i.e. the ‘immunological warriors’ of the brain. However, extensive knowledge is being accumulated about the functions of microglia beyond immunity. Nowadays, it is well accepted that microglial cells are highly dynamic and responsive, and that they intervene in a dual manner in many developmental processes that shape the central nervous system, including neurogenesis, gliogenesis, spatial patterning, synaptic formation and elimination, and neural circuit establishment and maturation. The differentiation and the pool of precursor cells were also shown to be under microglia regulation via bidirectional communication. In this concise review, I discuss our recent work in microglia-Pax6⁺ cell interactions in one of the circumventricular organs, the pineal gland. An analogy with the rest of the central nervous system is also presented. In addition, I briefly examine mechanisms of interaction between microglia and non-microglial cells in both health and disease. New avenues are also introduced, which may lead us to better comprehend the impact of microglia in physiological and pathological conditions.     

Immunomodulatory and antioxidative potential of herb (Pueraria tuberosa) in mice using milk as the carrier

Eighteen healthy male mice were divided into three equal groups and given specific diets for a period of 28 days: Group M were fed a normal synthetic diet (NSD) and milk; Group P were fed NSD and Pueraria tuberosa (PT) extract (0.4%), while the diet of group PM was NSD supplemented with PT extract (0.4%) and milk. The phagocytic activity and immunoglobulin A (in intestines) and immunoglobulin G (serum) levels increased significantly in comparison with group M in PT supplemented groups after a period of 28 days. Group P and Group PM showed significantly higher reduced glutathione level and significantly lowered thiobarbituric acid reactive substances levels in liver and red blood cells as compared to control.     

In Vitro Evaluation and Targeting of E. Coli Internalized by Endothelial Cells using Albumin Microspheres Loaded with Gentamicin

ABSTRACT

The purpose of this study was to evaluate the use of microencapsulated form of gentamicin and the traditional solution form for its intracellular bactericidal effect. Bovine serumalbumin (BSA) microspheres loaded with gentamicin were prepared by using Mini Spray Dryer. Human microvascular endothelial cells (HMECs) were exposed to increasing concentrations of Escherichia coli leading to internalization of E. coli. The internalized bacteria were targeted using either the microencapsulated or the solution form of gentamicin. The treatment groups using gentamicin solution form and microsphere form showed almost 46% and 86% inhibition in the growth of the internalized bacteria, respectively.