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1.
The in vitro interaction of soluble horseradish peroxidase (HRP) with homogeneous mono layers of mouse macrophages has been studied using sensitive biochemical and cytochemical techniques. The compartmentalization of HRP in extracellular and intracellular sites has been quantitatively evaluated. A significant fraction is bound to a serum-derived layer, which coats the surface of culture vessels and may be removed by appropriate washes. Macrophages interiorize HRP as a solute in pinocytic vesicles without appreciable binding of the glycoprotein to the plasma membrane. Uptake is directly proportional to the concentration of HRP in the culture medium. 1 x 106 cells ingest 0.0025% of the administered load per hr over a wide range of concentrations. Cytochemically, all demonstrable HRP is sequestered within the endocytic vesicles and secondary lysosomes of the vacuolar apparatus. After uptake, the enzymatic activity of HRP is inactivated exponentially with a half-life of 7–9 hr, until enzyme is no longer detectable. When macrophages have pinocytosed trace-labeled HRP-125I, cell-associated isotope disappears with a t ½ of 20–30 hr and they release monoiodotyrosine-125I into the culture medium. We were unable to obtain evidence that significant amounts of HRP (>2%) can be exocytosed after uptake, can exist intact on the cell surface, or can be digested extracellularly. It is difficult to reconcile these observations with several of the postulated mechanisms whereby macrophages are thought to play a prominent role in the induction of an immune response.  相似文献   

2.
激活巨噬细胞既是机体抵抗肿瘤和微生物感染的一类效应细胞,又是重要的免疫调节细胞。但是,激活巨噬细胞同时具有抗肿瘤作用和免疫抑制效应已被大量实验所证实。这种免疫抑制作用是肿瘤免疫治疗中亟待解决的一个问题。我们实验室近来的工作表明,用高剂量的脂多糖(LPS,10μg/ml)体外处理巯基乙醇酸钠诱发的小鼠腹腔巨噬细胞和培养的人体  相似文献   

3.
Cationic liposomes composed of sphingomyelin, cholesterol, and stearylamine were prepared with horseradish peroxidase trapped inside. Stable particles were formed in which 10–12% of the enzymic activity appeared to be located at, or near, the outer surface of the liposome. Adsorption and uptake of liposomes by HeLa cells were followed cytochemically by electron microscopy and quantitated by enzyme assay and by the distribution and fate of particles labeled with [14C]cholesterol and [125I]horseradish peroxidase. The particles were adsorbed by HeLa cells at least 300 times as efficiently as was free horseradish peroxidase. Many of the particles remained at the cell surface, but numerous membrane-bound cytoplasmic inclusions were observed to contain peroxidase-staining material. In addition, many areas of the cell membrane gave a positive staining reaction. It was concluded that many particles (presumably the larger ones) did not gain access to the interior of the cells, many were phagocytized, and some enzyme was transferred to the cell membrane, perhaps as a result of fusion of the liposomal membrane with the cell membrane.  相似文献   

4.
Mouse peritoneal macrophages have been studied in vitro after ingestion of treated rat, rabbit, or sheep erythrocytes. Under light microscopy, phagocytic vacuoles persist up to 24 h. Macrophages lose benzidine reactivity about 5 h after red cell ingestion, and they become prussian blue positive at 2 days. Ultrastructural studies show little or no ferritin in control macrophages not fed erythrocytes. In contrast, after red cell ingestion, ferritin is widely distributed in the cytoplasmic matrix and in some cytoplasmic granules by 48 h. The Golgi complex, pinocytic vacuoles, endoplasmic reticulum, nuclei, and mitochondria do not contain ferritin. Between 2 and 4 days, ferritin in cytoplasmic granules increases, concomitant with decrease in the ferritin in the cytoplasmic matrix. Evidence is presented suggesting that ferritin in the cytoplasmic matrix is translocated into cytoplasmic granules by autophagy. Polyacrylamide gel studies on macrophages after uptake of red blood cells labeled with radioiron confirm that macrophages produce radiolabeled ferritin by 4 days.  相似文献   

5.
本文报道了用生物化学方法测定离体小鼠比目鱼肌对 HRP 的胞纳作用。结果表明,在切断神经或切腱后引起萎缩的肌肉侧或在协同肌切腱后引起代偿性肥大的肌肉侧,与它们各自对照的正常肌肉侧相比,都可发生对 HRP 胞纳的明显增加。而在肉毒杆菌毒素中毒后引起萎缩的肌肉侧,和它正常的对照肌肉侧相比,却意外地不发生这种胞纳摄取的明显增加。本文的实验结果进一步证实。肌肉的胞纳增加并不一定导致肌纤维的变性和萎缩(例如代偿性肥大的肌肉);而肌纤维的变性和萎缩亦不一定需要肌肉的胞纳增加为前提(例如肉毒杆菌毒素中毒的肌肉)。本工作结果还提示:肌肉的胞纳增加有其神经原性和肌原性因素。本文还对肌肉胞纳增加的可能机制进行了讨论。  相似文献   

6.
本文报道了用辣根过氧化物酶(HRP)作为大分子标记物,以组织化学和生物化学方法观察了鸡前后背阔肌在去神经后的胞纳现象。结果表明,在去神经后发生肥大的前背阔肌和去神经后发生萎缩的后背阔肌同样都出现胞纳的明显增加。组织化学所观察的结果表明,浸泡在含 HRP 的任氏液中的有完整神经支配的前、后背阔肌只有极少数的肌纤维摄取 HRP,而在去神经的前、后背阔肌中则有不少的肌纤维内部出现 HRP 染色反应。这种反应在有的纤维表现为弥散性染色,有的表现为浓的 HRP 反应颗粒。生物化学的结果显示,去神经后的前、后背阔肌中 HRP 的相对含量分别比有神经支配的对照肌肉明显地增多54%和87%,我们在鸡前背阔肌用组织化学和生物化学所得的实验结果与 Thesleff 等人提出的关于肌肉萎缩机制的假设显然不符。本工作证实了肌肉的胞纳作用的增加并不一定最终导致肌纤维的变性和萎缩。  相似文献   

7.
目的研究子宫内膜异位症发生进程中腹腔巨噬细胞吞噬功能的变化规律。方法构造小鼠子宫内膜异位症模型,用流式细胞术检测造模前后腹腔巨噬细胞吞噬荧光微球数,计算吞噬率和吞噬指数代表巨噬细胞的吞噬能力。结果巨噬细胞吞噬率和吞噬指数分别为:未造模组[(10.1±0.82)%,0.17±0.01]、造模后第1d[(32.78±2.43)%,0.60±0.02]、第2d[(33.82±1.23)%,0.61±0.02]、第3d[(35.93±2.81)%,0.72±0.03]、第4d[(27.92±1.24)%,0.51±0.03]、第5d[(24.34±0.91)%,0.40±0.02]、第6d[(17.91±1.03)%,0.28±0.01]、第9d[(17.56±0.80)%,0.26±0.01I、第12d[(19.42±1.02)%,0.36±0.01]、第15d[(26.78±2.05)%,0.54±0.02]、第18d[(27.46±1.61)%,0.50±0.02]、第21d[(25.99±2.31)%,0.54±0.03]。造模后的小鼠腹腔巨噬细胞吞噬能力均显著高于未造模组,且呈现出三个阶段的改变:第1—5d为第1阶段,第6-12d为第2阶段,第15—21d为第3阶段,第1和第3阶段显著高于第2阶段(P〈0.01)。结论 子宫内膜异位症小鼠腹腔巨噬细胞的吞噬功能增强,且随时间呈现规律性变化特征,可能与子宫内膜的清除和异位存活有关。  相似文献   

8.
Mouse peritoneal macrophages in culture for 24 h were exposed to horse [55Fe]ferritin and rabbit antihorse [55Fe]ferritin antibody complex and the amount of 55Fe in the medium was assayed up to 2 days after the pulse uptake. Cell survival was assayed by photographing the same areas of the tissue culture Petri dish on successive days and by counting cell numbers per unit area. In experiments in which quantitative assay for cell death is negligible, about 10–20% of the iron ingested by pinocytosis or phagocytosis is released to iron-free medium containing either freshly dialyzed or deironized newborn calf serum (10%). Over the 2-day postpulse period, iron loss is linear. This loss of iron to the medium is significantly reduced by adding iron-saturated newborn calf serum in the postpulse recovery period. A significant portion of the iron released to the medium is bound to transferrin. When human serum is used in the tissue culture system, similar quantities (10–25%) of the ingested iron are lost to the medium 2 days after the pulse.  相似文献   

9.
腓肠肌内注射HRP后,用生物化学法测定坐骨神经、L_(4-6)节段背根和腹根神经的HRP含量。在戊巴比妥连续全身麻醉大鼠的HRP含量明显低于不麻醉的大鼠,而肌肉不活动(TTX中毒和切腱)大鼠神经组织中的HRP含量无甚变化。刺激神经不能改变麻醉大鼠的HRP含量。上述结果提示:除麻醉剂造成的肌肉不活动因素外,戊巴比妥对大鼠骨胳肌HRP的轴突摄取和逆行传送具有另外的抑制作用。已有研究报道:破伤风和单纯性疱疹病毒脑炎都是由于它们的毒素或病毒,通过外周神经摄取然后逆行传送到各级中枢而致病的。  相似文献   

10.
本实验利用扫描电镜观察小鼠腹腔巨噬细胞在体外吞噬鸡红血球过程大致可分为巨噬细胞接触、扑获、包绕鸡红血球和鸡红血球在巨噬细胞中内移等4个阶段。经厌氧小棒状杆菌处理的巨噬细胞呈现激活状态,比未经厌氧小棒状杆菌处理的巨噬细胞表现更大的膜活性,胞体铺展增大,突起多呈叶状或皱褶状,吞噬鸡红血球能力明显增强。经厌氧小棒状杆菌处理的巨噬细胞与U27癌细胞存在着接触,此时U27癌细胞易发生变性、坏死。  相似文献   

11.
Cell suspensions, obtained from bone marrow, spleen, thymus, lung, liver, and from peritoneal washings, were incubated in vitro with low concentrations of endo-toxin and the supernatant media assayed for colony-stimulating activity (CSA). Peritoneal cells were markedly responsive. The kinetics of CSA production in vitro by peritoneal cells were not remarkably different from that seen in vivo following intravenous administration of endotoxin. The activities of CSA prepared from peritoneal cells and serum were compared following serial dilution; both gave a similar linear relationship when plotted as a function of log-concentration. The bulk of the CSA was produced by adherent peritoneal cells. Separation of peritoneal cells by velocity sedimentation showed that the CSA-producing cell had a sedimentation velocity of 7 mm/hr. Cells with this sedimentation velocity were found to be large mononuclear cells which demonstrated adherence and phagocytosis.  相似文献   

12.
鱼类的巨噬细胞和高等脊椎动物的一样,在吞灭入侵的病原体方面起着极其重要的作用。探索在体外长期培养巨噬细胞的方法,有助于研究巨噬细胞的机能。Braun-Nesje等虽已从硬头鳟(Salmo gairdneri)等鲑科鱼类的头肾中分离出大量的巨噬细胞,并在体外培养了3个月之久,但因细胞不分裂,无法传代。本研究改用组织块培养法和饲养层技术探索长期培养巨噬细胞的方法,并获得成功。迄今巨噬细胞已在体外培养22个月,传代48次。细胞的原代培养分为三组。前两组是单独的脾或头肾的组织培养;第三组是脾与头肾的混合组织培养。培养液是Leibovitz’s L-15,外加20%胎牛血清,100 IU/ml青霉素和100μg/ml链霉素。巨噬细胞的吞噬活力用酵母菌Candida  相似文献   

13.
本文就长爪沙鼠腹腔巨噬细胞(MΦ)对流行性出血热病毒(EHFV)的敏感性进行了试验,用3株野鼠型(A9、R3、76-118)和1株家鼠型EHFV(R22),并用对EHFV敏感的Vero-E6细胞作对照,结果沙鼠腹腔巨噬细胞感染EHFV后,第1代第8天前即可查见明显的特异性荧光,第16天左右达高峰,病毒滴度≥10~(-7.5),与Vero-E6细胞比较,培养上清液的病毒滴度,沙鼠MΦ较Vero-E6细胞高1~4个对数,当感染病毒量很低时,在Vero-E6细胞内测不出特异性抗原,而在沙鼠MΦ内病毒仍可繁殖,滴度达10~(-5.(?)),中和试验、间接免疫荧光检测和荧光阻断试验均证明,沙鼠MΦ内繁殖的病毒确实为EHFV。  相似文献   

14.
小鼠对天花粉蛋白体内及体外免疫应答的基本特点   总被引:1,自引:0,他引:1  
C 57 BL/6 J小鼠在应用弗氏全佐剂或铝矾为佐剂结合天花粉蛋白免疫后都能引起抗原特异的IgE类抗体的反应以及其它Ig类抗体的反应;IgE的滴度和总的抗天花粉蛋白抗体的滴度的动态变化趋势基本一致,但并不完全同步。IgE类上升得较IgG等类抗体为慢,但上升的速度要快。脾和肠系膜淋巴结细胞分泌抗体的动态变化也和血清并不完全一致。天花粉蛋白在一定浓度下能抑制小鼠T淋巴细胞在体外的抗原特异的增殖反应和ConA反应。这抑制并不限于增殖过程的启动。补充外源性的IL-2也不能消除这抑制作用。天花粉蛋白加热变性后丧失了对小鼠淋巴细胞的毒性,并能引起经未变性天花粉蛋白体内致敏的小鼠的T淋巴细胞在体外的明显增殖。应用微量的天花粉蛋白为抗原,以及少量的无凝集素的conA条件培液等能在体外诱发致敏的B淋巴细胞产生二次抗体应答。  相似文献   

15.
乙醇对着床前小鼠胚胎体外发育的影响   总被引:1,自引:0,他引:1  
用含不同浓度乙醇的Whitten氏培养液对小鼠2细胞、4细胞、8细胞和桑椹期胚胎分别进行体外培养,研究了乙醇对小鼠不同发育时期胚胎体外发育的影响。首先利用含0、0.1%、0.5%、1.0%、1.5%、2.0%、3.0%、5.0%和10.0%乙醇的Whitten氏培养液对2细胞胚胎进行培养,发现小鼠2细胞胚胎对培养液中乙醇浓度的耐受极限在1.5%左右。然后又用含1%和3%乙醇的Whitten氏培养液分别对小鼠2细胞、4细胞、8细胞和桑椹期胚胎进行培养。结果发现:含1%乙醇的培养液对于8细胞胚胎和桑椹胚的囊胚形成有促进作用,而在2细胞和4细胞胚胎中则影响不明显。3%乙醇则对各期胚胎均有不同程度的抑制作用,但随着胚胎发育其对乙醇的耐受力逐渐增强。  相似文献   

16.
经研究表明顺式氯氰菊酯、甲氰菊酯、氟氰菊酯、氰戊菊酯在正辛醇——水相中的分配系数(logP)分别为6.13,5.50,5.55和4.02。离体培养的大白鼠原代肝细胞对上述杀虫剂(除氟氰菊酯外)的吸收系数(q值)分别为322.6,281.1,201.9。上述杀虫剂在离体培养的原代肝细胞中降解很快,温育30分钟后降解速率分别为90.0%(顺式氯氰菊酯)、86.2%(甲氰菊酯)、69.5%(氰戊菊酯)。同时有明显的减少离体培养的鼠肝细胞中P-450含量的作用,其中以溴氰菊酯和顺式氯氰菊酯作用较明显。在溴氰菊酯处理组中,随杀虫剂浓度的升高,这种减少P-450含量的作用明显增强。检查温育反应90分种后的细胞悬浮反应液,对照组仍维持高的细胞存活率(74.4%和91.2%),而杀虫剂处理组,除甲氰菊酯处理组仍有42.4%的存活率外,其余各杀虫剂(溴氰菊酯各浓度组和顺式氯氰菊酯处理组)均未检出存活的细胞。结果表明,试验所用的几种拟除虫菊酯类杀虫剂具有一定的细胞毒性。它们在鼠肝细胞中的降解代谢可能主要不是由于多功能氧化酶起作用。另外,杀虫剂的亲脂性与q值及在肝细胞中的降解速率三者间有一定的正相关。  相似文献   

17.
Highly proliferative normal human epidermal keratinocytes (NHK) were isolated from human foreskin biopsies, cultivated in serum-free medium and characterized by flow cytometry. The expression of cytokeratin 19, cytokeratin 14 and vimentin indicated that the suspension contained a high percentage of undifferentiated cells of the basal epidermal layer. The NHK were transfected in vitro with lipid/DNA complexes made of Effectene or Lipofectamine and different reporter genes. The transfection efficiency of Effectene/DNA complexes was 20fold higher compared to Lipofectamine. Transfected keratinocytes continued to grow and developed within 2 weeks a cellular multilayer (3-D culture). Areas of transfected cells were detected within this layer.  相似文献   

18.
The concentration of horseradish peroxidase in total particulate fractions from the kidney cortex did not change much during the first few hours after injection, as long as most of the injected protein was not yet cleared from the blood. It decreased at a rate of 6–8% per hr afterwards. The concentration of peroxidase in total particulate fractions increased in proportion to the load (dose) over a wide range, suggesting that a constant fraction of the protein was reabsorbed by micropinocytic vesicles into the tubule cells from the glomerular filtrate. The amount of peroxidase excreted in the urine also increased in proportion to the injected dose. The proportion of peroxidase taken up by the liver, however, decreased several times when the dose was increased. A marked decrease of protein uptake into the kidney cortex and an increase of urinary excretion were observed when rats received a second, equal dose of peroxidase 4 hr after the first injection, and the rate of clearance of peroxidase from the blood was decreased after the second injection. The liver, on the other hand, took up almost twice as much peroxidase after two injections as after one. The uptake of peroxidase by the kidney cortex increased with age. Cytochemical observations on the preferential absorption of peroxidase by certain cell types and segments of the renal tubules in relation to dose are reported.  相似文献   

19.
The cell proliferation of pre-implanted mouse embryos was investigated after development in vivo and in vitro. The studies were started at the pronuclear stage, 2 h post conception (p.c.) and continued until the hatching of blastocysts, 120–144 h p.c. The number of cell nuclei, the DNA content of each nucleus, the mitotic index and the labelling index were determined. From these data it was possible to calculate the length of the cell generation cycle and its various phases. With the exception of the first cell cycle the S-phase was constant. The G1- as well as the G2-phase varied in length during the different cell cycles. From 31–72 h p.c. the increase in cell number was exponential. After cultivation in vitro this increase was smaller than in vivo. At later periods the proliferation rate decreased with proceeding development. In late blastocysts most of the cells were in the G1-phase. The development of the embryos was somewhat faster in vivo than in vitro. But in principle conditions were comparable.  相似文献   

20.
本实验观察了四种阿片受体亚型的激动剂对大鼠腹腔巨噬细胞(Mφ)释放过氧化氢(H_2O_2的影响。吗啡、β-内啡肽和κ受体激动剂NDAP能抑制Mφ释放H_2O_2。纳洛酮能翻转吗啡和β-内啡肽的这一作用,κ受体阻断剂nor-BNI能拮抗NDAP的作用。δ受体激动剂DADLE仅在高浓度时才抑制Mφ释放H_2O_2。以上结果表明,Mφ上可能存在若干类型阿片受体,其中μ、ε和κ受体对Mφ释放H_2O_2具有明显的调节作用。  相似文献   

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