巨噬细胞在激活过程中形态和功能的改变

实验用石腊油,糖元及淀粉溶液给小鼠腹腔注射,经过16小时,腹腔巨噬细胞(Macrophae-Mφ)的数目开始增多,体积变大。细胞内乳酸脱氢酶、酸性磷酸酶及酸性醋酸萘酚酯酶的活性显著增强;三磷酸腺苷酶、琥珀酸脱氢酶及氨基肽酶的活性稍增强。巨噬细菌吞噬鸡红细胞的能力增强。至注后72小时,上述改变更加明显。表明糖元、淀粉、石腊油可以激活小鼠腹腔巨噬细胞。     

氧化低密度脂蛋白及溶血卵磷脂对巨噬泡沫细胞胆固醇外流的影响

目的:观察氧化低密度脂蛋白(OxLDL)及其成分溶血卵磷脂(LPC)对小鼠腹腔巨噬泡沫细胞胆固醇外流的影响及其机制的初步探讨。方法:(1)以载脂蛋白AI(apoAI)分别诱导OxLDL和乙酰化低密度脂蛋白(AcLDL)负载小鼠腹腔巨噬细胞所形成的巨噬泡沫细胞, 观察其胆固醇外流情况。(2)分离正常及apoE基因缺陷(E⁰)小鼠腹腔巨噬细胞, 以AcLDL负载形成巨噬泡沫细胞, 分别以LPC及apoAI作为诱导物, 观察其胆固醇外流情况。结果:(1)apoAI能引起AcLDL组巨噬泡沫细胞胆固醇大量外流, 而OxLDL组外流明显受阻。(2)LPC能引起正常组小鼠腹腔巨噬泡沫细胞胆固醇外流, 且呈剂量效应关系, 但E⁰组未见明显外流;apoAI能引起两组的胆固醇外流, 且外流量显著高于LPC。结论:(1)OxLDL能造成胆固醇外流途径受阻。(2)LPC能促进巨噬泡沫细胞胆固醇外流, 可能主要通过apoE途径来进行。     

溶血卵磷脂对巨噬泡沫细胞胆固醇外流的影响

目的:探讨溶血卵磷脂(LPC)对巨噬泡沫细胞胆固醇外流的影响,为动脉粥样硬化(AS)的防治研究提供理论依据。方法:分离培养小鼠腹腔巨噬细胞,密度梯度超速离心法分离人血浆低密度脂蛋白(LDL),乙酰化后形成乙酰化低密度脂蛋白(AcLDL),用AcLDL负载巨噬细胞使之形成巨噬泡沫细胞模型。用酶学荧光法检测细胞胆固醇外流,用乳酸脱氢酶(LDH)检测试剂盒检测培养基中LDH活性来反映LPC的细胞毒性。结果:LPC处理巨噬泡沫细胞24h后,培养基中胆固醇含量明显高于对照组(1.7-4倍),细胞内胆固醇含量明显低于对照组。且LPC引起细胞胆固醇外流增加同时,培养基中LDH活性并没有明显差异。结论:在10-80μmol/L剂量范围内,LPC可以剂量依赖性地促进巨噬泡沫细胞胆固醇外流,且这一效应与LPC的细胞毒性之间没有关系。     

溶血卵磷脂对巨噬泡沫细胞胆固醇外流的影响

目的：探讨溶血卵磷脂（LPC）对巨噬泡沫细胞胆固醇外流的影响，为动脉粥样硬化（AS）的防治研究提供理论依据。方法：分离培养小鼠腹腔巨噬细胞，密度梯度超速离心法分离人血浆低密度脂蛋白（LDL），乙酰化后形成乙酰化低密度蛋白（AcLDL),用AcLDL负载巨噬细胞使之形成巨噬泡沫细胞模型。用酶学荧光法检测细胞胆固醇外流，用乳酸脱氢酶（LDH）检测试剂盒检测培养基中LDH活性来反映LPC的细胞毒性。结果：LPC处理巨噬泡沫细胞24h后，培养基中胆固醇含量明显高于对照组（1．7－4倍），细胞内胆固醇含量明显低于对照组。且LPC引起细胞胆固醇外流增加同时，培养基中LDH活性并没有明显差异。结论：在10－80μmol/L剂量范围内，LPC可以剂量依赖性地促进巨噬泡沫细胞胆固醇外流，且这一效应与LPC的细胞毒性之间没有关系。     

小鼠辐射损伤与防护后腹腔巨噬细胞的扫描电镜观察

本实验用扫描电镜观察了~(60)C0-r射线8 Gy全身一次照射后第6天小鼠腹腔巨噬细胞吞噬鸡红细胞功能的变化。发现照后巨噬细胞的吞噬功能受到抑制,巨噬细胞对鸡红细胞的粘附,固定、捕获和鸡红细胞在巨噬细胞内被消化几个过程延迟;而照射前给予5-羟色胺(5-HT)腹腔注射其吞噬功能受到保护。     

花青素对小鼠巨噬泡沫细胞胆固醇外流的影响

目的：研究植物化学物质花青素对小鼠巨噬泡沫细胞胆固醇外流的影响，探讨花青素促进巨噬泡沫细胞胆固醇外流的分子机制。方法： 制备乙酰化低密度脂蛋白（AcLDL），以其负载小鼠腹腔巨噬细胞形成巨噬泡沫细胞，观察不同浓度花青素Cy-3-G和Pn-3-G对巨噬泡沫细胞胆固醇外流的影响以及调节胆固醇外流有关的基因过氧化物酶体增殖物激活受体-γ（PPAR-γ）表达的情况。结果：AcLDL可促进胆固醇在巨噬细胞中大量蓄积，造成泡沫细胞的形成。花青素Cy-3-G和Pn-3-G能引起巨噬泡沫细胞内胆固醇的大量外流，并且增加PPAR-γ基因的表达。结论：花青素Cy-3-G和Pn-3-G促进胆固醇外流的作用与其增加PPAR-γ基因的表达有关。     

沉默HDAC6对嗜肺军团菌干扰RAW264.7自噬作用的影响

目的 以嗜肺军团菌感染HDAC6基因沉默的RAW264.7细胞为研究对象,检测自噬流及自噬相关因子表达水平的变化,探究HDAC6在嗜肺军团菌干扰巨噬细胞自噬中的作用机制。方法 利用RNAi技术介导基因沉默,构建shRNAHDAC6细胞,Western blot验证沉默效果。用嗜肺军团菌活菌和灭活菌[感染复数(MOI)=50]分别感染RAW264.7、sh-NC、shRNA-HDAC6细胞6、12、24 h。应用自噬双标质粒pmCherry-C1-EGFP-LC3B检测巨噬细胞自噬流的变化;透射电镜观察嗜肺军团菌感染24 h后各组细胞内的自噬小体和自噬溶酶体;实时荧光定量PCR及Western blot法检测AMBRA1、ATG9B、P62、Beclin1、α-tubulin、LC3B的表达水平。结果 与RAW264.7对照组相比,shRNA-HDAC6细胞的HDAC6蛋白表达水平显著降低(P<0.05);自噬双标质粒检测自噬流结果显示,嗜肺军团菌活菌及灭活菌感染RAW264.7细胞,自噬流均减弱,沉默HDAC6后嗜肺军团菌感染巨噬细胞自噬流增加。透射电镜可观察到嗜肺军团菌感染巨噬...     

尘粒对巨噬细胞自噬的影响

目的： 研究巨噬细胞吞噬尘粒后的自噬变化，探讨尘粒引起巨噬细胞自噬的机理。方法: 利用从肺部手术病人切除的支气管肺淋巴结，做石蜡切片和Wilder染色，观察组织结构变化。从大鼠腹膜腔取巨噬细胞，用碳粒处理，观察碳粒对巨噬细胞自噬功能的影响。将淋巴结和吞噬碳粒后的细胞做超薄切片，观察巨噬细胞内的吞噬体、自噬体和溶酶体的结构和分布。利用透射电镜和TUNEL染色法观察淋巴结尘细胞和吞噬碳粒细胞中的凋亡细胞。结果: 在成人淋巴结，巨噬细胞内的尘粒明显沉积，胶原纤维增生，微血管密度增加。在尘细胞和吞噬碳粒细胞内，除含有吞噬体外还含有较多的自噬前体、自噬体和自噬溶酶体。在自噬体内常含有线粒体、尘粒或碳粒。在尘细胞和吞噬碳粒后的细胞中都可见到TUNEL染色阳性细胞。透射电镜下可见凋亡细胞的核固缩或凋亡小体。结论: 尘粒沉积可引起巨噬细胞的自噬功能增强，并可出现凋亡。自噬对于巨噬细胞清除尘粒和损伤的线粒体具有重要作用。     

TNF-α对小鼠腹腔渗出细胞抗真菌活性的影响

目的：研究TNF—α对小鼠腹腔渗出细胞的激活和杀菌活性的效应。方法：以IL-12、IL-18、IFN—γ、TNF-α及抗体诱导小鼠腹腔渗出细胞和巨噬细胞，应用ELISA法测定细胞因子变化，Griess反应法测定培养上清液中NO的含量，检测巨噬细胞内新型隐球菌菌落数。结果：IL-12和IL-18联合应用协同诱导腹腔渗出细胞产生TNF—α，且能被IFN—γ抗体所抑制。IFN—γ、TNF-α协同诱导巨噬细胞产生NO和增强其杀伤新型隐球菌活性。结论：TNF—α在细胞因子相互调节诱导增强巨噬细胞杀真菌活性中起重要作用。     

甲基莲心碱对RAW264.7巨噬细胞泡沫化的影响

目的探讨甲基莲心碱(Nef)对巨噬泡沫细胞形成的作用及机制。方法采用体外培养小鼠巨噬细胞系RAW264.7细胞,ox-LDL诱导建立泡沫细胞模型,用Nef进行干预。油红O染色观察细胞内脂质堆积情况,酶比色法定量细胞内总胆固醇和胆固醇酯的变化,免疫荧光和流式细胞术分析CD36受体蛋白表达,RT-PCR检测CD36受体mRNA表达。结果与ox-LDL诱导组相比,Nef保护组巨噬细胞的油红O染色阳性细胞数和细胞内脂质含量均显著减少;同时CD36受体蛋白和mRNA表达明显降低。结论Nef可抑制ox—LDL诱导的RAW264.7巨噬细胞泡沫化,该作用可能与Nef下调巨噬细胞CD36受体表达,从而减弱巨噬细胞对ox—LDL的摄取有关。     

Release of hydrogen peroxide and expression of HLA-DR and transferrin receptors by monocytes and peritoneal macrophages from patients undergoing continuous ambulatory peritoneal dialysis and normal controls

Peritoneal macrophages from patients on continuous ambulatory peritoneal dialysis (CAPD) were investigated with respect to their ability to release H2O2 and express HLA-DR and transferrin receptors (TfR). Release of H2O2 and the proportion of cells expressing HLA-DR were significantly reduced in CAPD macrophages compared with normal peritoneal macrophages but were both similar to blood monocytes. In contrast, about 17% of CAPD peritoneal macrophages and 23% of CAPD blood monocytes expressed TfR but normal peritoneal macrophages and blood monocytes were always negative. These results suggest that the peritoneal macrophages from CAPD patients are relatively immature cells, possibly due to the rapid turnover of cells in CAPD.     

Influence of cell sources, stimulating agents, and incubation conditions on release of interleukin-1 from chicken macrophages

Experiments were conducted to determine the cell source, stimulating agents, and incubation conditions that maximize interleukin-1 (IL-1) release by chicken macrophages/monocytes. Thymocyte co-mitogen proliferation was used to assay IL-1 activity of conditioned or partially purified supernatants. Monolayers of a transformed chicken macrophage cell line, HD11, released greater amounts of IL-1 than adherent cells isolated from peripheral blood, peritoneal cavity, or spleen. E. coli endotoxin and heat-killed S. aureus induced greater release of IL-1 by HD11 and splenic macrophages than latex or a super induction protocol with mezerien. Blocking macrophage eicosanoid synthesis with indomethacin did not influence IL-1 release from HD11 macrophages. Removing low molecular weight compounds from conditioned supernatants by dialysis did not influence IL-1 activity. IL-1 release was increased by incubating macrophages at 42 C compared to 39 C. Thymocyte co-mitogenic activity of IL-1 was increased by incubating thymocytes at 42 C compared to 39 C. Species cross reactivity between chicken and mammalian IL-1 was also investigated. Chicken IL-1 had slight co-stimulation activity on murine thymocytes, but murine and human IL-1 were without activity on chicken thymocytes.     

Functional and biochemical properties of rat Kupffer cells and peritoneal macrophages

Functional and biochemical techniques were used to further characterize heterogeneity between rat Kupffer cells and peritoneal macrophages. Both macrophage cell types were found to phagocytize antibody coated sheep red blood cells in a time-dependent manner. However, Kupffer cells were two to three times more phagocytic than were peritoneal macrophages. In contrast, the peritoneal cells released significantly more superoxide anion in response to the complement cleavage product, C5a and the phorbol ester tumor promoter, 12-0-tetradecanoyl-phorbol-13-acetate, and produced more hydrogen peroxide than did the liver macrophages. Both cell types responded chemotactically to C5a. These results suggest that macrophages may develop specialized functions depending on the needs of their local environment. Using one and two dimensional SDS-polyacrylamide gel electrophoresis, we also compared the production of newly synthesized proteins by Kupffer cells and peritoneal macrophages. In general, the macrophages were found to produce similar types and numbers of proteins with some exceptions. These included proteins that were unique to peritoneal macrophages and other proteins observed only in Kupffer cells. The production of these proteins in liver macrophages did not appear to correlate with levels of functional activation, but may be more related to the tissue origin of the cells.     

A monoclonal antibody (BMA-1) reactive with murine B cells as well as resident and elicited but not activated macrophages

Hybridoma technology has been employed to prepare a monoclonal antibody that recognizes a subpopulation of mononuclear leukocytes. Enzyme-linked immune assay revealed a cell clone producing a monoclonal antibody reactive with elicited but not activated C57Bi/6 peritoneal macrophages. Detailed analyses using fluorescence flow cytometry demonstrated that this monoclonal antibody binds to B cells, B cell blasts, as well as to the resident and elicited macrophages, but not to activated macrophages, T cells, red blood cells, or syngeneic fibroblasts. This antigen has been designated BMA-1. Antigenic expression is greatest upon resident macrophages. A bimodal level of expression is found on elicited macrophages while activated macrophages possess low levels of expression. The unique cellular distribution of this antigen indicates that it is lost during macrophage differentiation to the activated state. Immunoprecipitation studies indicate that this antigen is composed of multiple subunits; the primary subunit possesses a molecular weight of 38,000. This new tool should be valuable in the analysis of heterogeneous macrophage populations and in defining molecular differentiation pathways.     

Human eosinophils are more toxic than neutrophils in antibody-independent killing

Eosinophils (EOSs) are implicated in damaging host tissues in diseases such as asthma and eosinophilic gastroenteritis. In the present study, we assessed the cytotoxicity of human EOSs from peripheral blood of patients with eosinophilia and from peritoneal fluid of patients undergoing continuous peritoneal dialysis and compared them to normal neutrophils. Cytotoxicity was measured by the release of 51chromium from cultured tumor cells and chicken erythrocytes. Both EOSs and neutrophils were separated on discontinuous Percoll gradients with greater than 95% purity. The granulocytes were activated by preincubation in an ice bath with phorbol myristate acetate and washed before incubation with the target cells. The EOSs lysed significantly more tumor cells (K562, Raji, and CEM lines) in an 18-hour assay than did neutrophils, and no significant difference was found between the peritoneal and blood EOSs. The EOSs were also much more efficient than neutrophils in lysing chicken erythrocytes when they were activated by granulocyte-macrophage colony-stimulating factor instead of phorbol myristate acetate. Cytolysis by EOSs is mediated by both oxidative and nonoxidative mechanisms, as indicated by experiments with cells from patients with chronic granulomatous disease. Thus, EOSs are much more cytotoxic than neutrophils and potentially much more damaging to patients with eosinophilia.     

The immunity of splenic and peritoneal F4/80<Superscript>+</Superscript> resident macrophages in mouse mixed allogeneic chimeras

Mixed allogeneic chimeras are emerging as a prospective approach to induce immune tolerance in clinics. However, the immunological function of macrophages in mixed chimeras has not been evaluated. Using a B6-->BALB/c mixed chimera model, we investigated the phenotype and function of F4/80(+) resident peritoneal exudate macrophage (PEMs) and splenic macrophages (SPMs) in vitro and in vivo. Recipient F4/80(+)PEMs and SPMs in mixed chimeras expressed significantly lower levels of MHC-II, CD54, and CD23 than those in non-chimeric mice before lipopolysaccharide stimulation. Recipient F4/80(+)PEMs and SPMs in mixed chimeras induced normal cell proliferation and delayed-type hypersensitivity of allo-T cells, but they induced more IFN-gamma and IL-2 products and less IL-10 and TGF-beta products of allo-T cells compared with those of non-chimeras. Furthermore, recipient F4/80(+)PEMs and SPMs had significantly higher phagocytotic capacity against chicken red blood cells or allo-T cells than those of controls while they had normal phagocytosis to Escherichia coli. Although some slight but significant alterations of recipient macrophages have been detected, these results provide direct evidences for the efficient immunity of recipient macrophages in mixed allogeneic chimeras. The present study also, for the first time, offered basic information for macrophages maturing in heterogeneous environments.     

The association of H-2 antigens and EAC receptors on the surface of peritoneal cells.

The exposure of murine peritoneal cells to anti-H-2 sera results in a diminished expression of H-2 antigen on the cell surface. Concomitant with this "H-2 modulation" the capacity of macrophages to bind sheep red blood cells coated with antibody and complement (EAC) was markedly diminished. In contrast, there was no change in the capacity of modulated macrophages to bind sheep red blood cells coated with antibody alone (EA). Antibodies to K end H-2 specificities were more effective in reducing the binding of EAC than antibodies to D end H-2 specificities. Exposure of peritoneal cells to O or Ly antisera had no effect on the formation of EAC rosettes. Exposure of peritoneal cells to anti-H-2 sera, under conditions which would not allow modulation of H-2 antigens, also prevented the reduction of EAC binding. Thus, the EAC receptors and H-2 antigenic specificities seem to be closely related on the surface of peritoneal cells, but constitute distinct cell surface structures. Preliminary evidence indicates that vinblastine, a microtubule depolymerizing agent, may disrupt the close association of EAC receptors and H-2 antigens. It is suggested that the association of EAC receptors and K end H-2 determinants on the membrane of macrophages may have implications for the regulation of the immune response by H-2-linked Ir genes.     

用血红蛋白酶释放法检测巨噬细胞的吞噬能力

以鸡红细胞作为靶细胞,小鼠腹腔巨噬细胞为效应细胞研究了巨噬细胞的吞噬能力。经低渗处理后,血红蛋白酶释放的多少以它氧化邻苯二胺所产生的颜色反应表示吞噬百分比。对红细胞数与OD值关系、不同粘附时间和不同吞噬时间与吞噬能力的关系进行了研究。方法灵敏、可靠、客观,有推广应用的价值。     

Characterization of human peritoneal dendritic cell precursors and their involvement in peritonitis

Scattered evidence suggests that the human peritoneal cavity contains cells of the dendritic cell (DC) lineage but their characterization is missing. Here, we report that the peritoneal cavity of normal subjects and of stable patients on peritoneal dialysis (PD) contains a population of CD14(+) cells that can differentiate into DCs or macrophages. Within this pool, we characterized a CD14(+)CD4(+) cell subset (2.2% of the peritoneal cells) fulfilling the definition of myeloid DC precursors or pre-DC1 cells. These cells expressed high levels of HLA-DR, CD13, CD33, and CD86, and low levels of CD40, CD80, CD83, CD123, CD209, TLR-2 and TLR-4. These cells retained CD14 expression until late stages of differentiation, despite concomitant up-regulation of DC-SIGN (CD209), CD1a, CD80 and CD40. Peritoneal pre-DC1 cells had endocytic capacity that was down-regulated upon LPS/IFN-gamma stimulation, were more potent allo-stimulators than peritoneal CD14(+)CD4(-/lo) cells and monocyte-derived macrophages, and induced Th1 cytokine responses. More importantly, the number of peritoneal pre-DC1 cells increased during PD-associated peritonitis, with a different profile for Gram positive and Gram negative peritonitis, suggesting that these cells participate in the induction of peritoneal adaptive immune responses, and may be responsible for the bias towards Th1 responses during peritonitis.     

糖原诱出小鼠腹腔中性粒细胞对肿瘤细胞杀伤能力的测定

研究证明糖原具有显著性的诱发小鼠腹腔中性粒细胞的作用；糖原诱出的小鼠腹腔中性粒细胞对腹水型Ｓ１８０肿瘤细胞的细胞毒性杀伤能力与生理盐水诱出的腹腔细胞相似，但低于糖原活化的巨噬细胞，研究结果表明糖是一种理想的小鼠腹腔中性粒细胞诱导剂。糖原诱出的小鼠腹腔中性粒细胞具有一定程度的抗肿瘤能力，但不如糖原诱发的巨噬细胞的抗肿瘤作用显著。