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The role of cytokines in monocyte apoptosis.   总被引:2,自引:0,他引:2  
Survival or apoptosis, activation and differentiation, phagocytosis and antigen presentation, migration or participation in granuloma formation are features of freshly recruited blood-borne monocytes in the local environment. In this presentation we describe that human monocytes undergo spontaneous apoptosis in vitro which involves Fas/FasL interactions, and that proinflammatory cytokines such as tumor necrosis factor-alpha (TNFalpha), interleukin-1beta and granulocyte-monocyte-colony-stimulating factor prevent spontaneous apoptosis. In vitro infection of purified monocytes with low numbers of Mycobacterium tuberculosis H37Rv prevents spontaneous apoptosis. The apoptosis-preventing effect is correlated to the release of TNFalpha and not due to phagocytosis per se. Furthermore, the minor subset of CD64-negative monocytes is found to be less susceptible to recall antigen-activated CD4-positive T cell-mediated apoptosis than CD64-positive monocytes. Finally, recent findings of our group indicate that the chemokine platelet factor 4 protects monocytes from spontaneous apoptosis and induces the differentiation of monocytes into macrophages. From these findings we conclude that monocyte recruitment, their survival, their differentiation and their functional activity at the site of inflammation are regulated by a cytokine network which needs to be further analyzed in order to design strategies for immune intervention.  相似文献   

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Abdominal fat tissue aspirates from 12 patients with biopsy-proved amyloidosis were investigated by different morphologic techniques. By light microscopy, after staining of the fat tissue aspirates with Congo red and examination with a polarizing microscope, positive results were obtained in nine patients with amyloidosis, two of the three with primary (AL) amyloidosis and seven of the nine with secondary (AA) amyloidosis. By indirect immunofluorescence, using AA antiserum, positive results were obtained in five of the nine cases of AA amyloidosis (aspirates from these five patients were positive on Congo red staining). By electron microscopy, amyloid fibrils were observed in five cases of amyloidosis (two of the AL and three of the AA type, all positive on Congo red staining). Although amyloid was demonstrated less frequently by immunofluorescence and electron microscopy, perhaps because of the small numbers of fat particles examined, it seems that, with Congo red staining, abdominal fat tissue aspiration is a simple and sensitive method for the diagnosis of amyloidosis. Immunofluorescence studies allow discrimination between the different types of amyloidosis. The method could be used in patients in whom other types of tissue biopsy are not recommended because of risks of bleeding or other problems.  相似文献   

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A correlated histochemical and pharmacological study was undertaken to establish the presence, origin, and possible function of nerve fibers containing a galanin-like peptide in the mudpuppy (Necturus maculosus) heart. Whole mount preparations of septum-sinus venosus or atria and sections of ventricular muscle were prepared for immunocytochemistry. Galanin-immunoreactive fibers were found coursing diffusely across the septum-sinus venosus to form complex networks over cardiac muscle strands. Individual atrial muscle strands were densely innervated by galanin-immunoreactive fibers and galanin-immunoreactive fibers were also observed in the epicardial and myocardial layers of the ventricle. Most of the parasympathetic postganglionic neurons in the cardiac ganglion and many of the small intensely fluorescent-like cells exhibited galanin immunoreactivity. Galanin-immunoreactive fibers were present in the nerve trunks connecting clusters of parasympathetic postganglionic neurons. Close associations between galanin-positive fibers and individual parasympathetic postganglionic neurons were also observed. The presence of the galanin-immunoreactive fibers was similar in preparations taken from animals pretreated with 6-hydroxydopamine to that seen in preparations taken from control animals, indicating that the galanin-positive fibers were not sympathetic postganglionic axons. Moreover, the galanin-immunoreactive nerve fibers were separate from fibers containing substance P and/or calcitonin gene-related peptide that have previously been shown to be processes of afferent fibers. In twitch-tension experiments, galanin in the range 1 x 10(-7) to 1 x 10(-6) M caused cardioinhibition of spontaneously beating isolated septal-sinus venosus preparations. Galanin also produced a concentration-dependent (1 x 10(-7) to 1 x 10(-6) M) decrease in the twitch-tension development of electrically stimulated atrial or ventricular preparations. Local application of galanin produced hyperpolarization of cardiac muscle fibers in both isolated septal-sinus venosus preparations and atrial preparations. The response of individual parasympathetic ganglion cells to local application of galanin varied between neurons; some neurons were depolarized whereas others were hyperpolarized. We conclude that a galanin-like peptide is contained in both the parasympathetic postganglionic neurons and small intensely fluorescent-like cells and their processes. Further, we hypothesize that in the case of the parasympathetic postganglionic neurons, the galanin-like peptide may work in conjunction with acetylcholine to regulate cardiac activity.  相似文献   

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PROBLEM: If immunological factors play a role in the pathogenesis of recurrent miscarriage (RM), it is likely that associations between alleles of classical human leukocyte antigen (HLA) genes and RM exist. Our aim was to investigate HLA-C alleles in RM couples and HLA-DR and -DQ polymorphism in women with unexplained RM. METHOD OF STUDY: HLA-C alleles were investigated in 35 RM and 30 control couples and HLA-DR and -DQ allogenotypes were investigated in 234 RM patients and 360 controls. All HLA investigations were undertaken by DNA based methods. RESULTS: We found no difference between the RM and control couples in the degree of paternal incompatibility for maternal HLA-C alleles and the distribution of the two HLA-C supertypic specificities that are recognized differently by p58 killer cell inhibitory receptor (KIR) positive natural killer (NK) cells was similar in the two groups. In 97 women with at least four previous miscarriages, significantly higher frequencies of the HLA-DR1,DQ5 and -DR3,DQ2 haplotypes were found compared with 360 controls (P < 0.05 after correction for multiple comparisons). Among 94 RM patients followed prospectively, those with HLA-DR1 and/or -DR3 had a 62% miscarriage rate compared with only 29% among those without these alleles (P < 0.05). A large family study indicated that HLA-DR1 and/or -DR3 positive sisters and brothers' wives of probands with RM had an odds ratio of 5.0 for miscarrying their pregnancies compared with corresponding HLA-DR1 and -DR3 negative relatives. Finally, a meta-analysis of relevant studies based on a MEDLINE search showed that HLA-DR1, -DR3, and -DR4 were significantly increased in Caucasian women with RM. CONCLUSIONS: HLA-DR1, -DR3, and maybe -DR4 show association to RM in Caucasian women whereas no association to classical HLA class I genes including HLA-C can be detected in RM couples. The mechanism by which class II alleles confer susceptibility to RM might be by predisposing to hypersecretion of certain cytokines, e.g., tumor necrosis factor (TNF)-alpha at the feto-maternal interface.  相似文献   

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PROBLEM: Ovarian follicles undergo a dynamic change to provide a mature ovum, and the process involves angiogenesis, follicular cell proliferation and leukocyte recruitment. Midkine (MK) is a heparin-binding growth factor that has angiogenic, mitogenic, and chemotactic activities. In the present study, we investigated the presence of MK and its possible role in human ovarian follicles. METHOD OF STUDY: Follicular fluid (FF) and luteinized granulosa cells (LGC) were collected from women undergoing in vitro fertilization and embryo transfer. Expression of MK protein in FF was examined by Western blotting. Concentrations of MK, estradiol and oxygen in FF were measured. 5-bromo-2'-deoxyuridine (BrdU) incorporation assay was performed in LGC. Normal ovarian tissues were obtained surgically and used in in-situ hybridization of MK mRNA. RESULTS: The presence of MK protein was verified in FF. MK mRNA was expressed in both granulosa cells and theca cells of large follicles. There is a significant negative correlation between the concentrations of MK and oxygen in FF, and a significant positive correlation between the concentrations of MK and estradiol. MK promoted BrdU uptake in LGC. CONCLUSION: The present findings imply that hypoxic condition, a characteristic of growing follicles, associates with the production of MK. Given that MK is involved in granulosa cell proliferation and estradiol production in developing follicles, MK may play a role as a local regulator in the human ovary.  相似文献   

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K Sato  S Abe 《Immunology》1975,28(2):293-299
The number of splenic plaque-forming cells significantly increased in bursectomized chicks immunized secondarily with SRBC. Further experiments using rabbit antiserum specific to the bursa of Fabricius indicate that the different types of antibody-producing cells might be engaged in the synthesis of IgM in bursectomized chicks. The possible presence of a bursa-independent, IgM-producing system in chicks is suggested.  相似文献   

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Histologic study of the hypophyseal component of a benign cystic ovarian teratoma disclosed elements that resembled sellar adenohypophysis, pars intermedia, and neurohypophysis. Histochemical dye methods revealed secretory cells with cytologic and granule-staining characteristics of somatotrophs, mammotrophs, melanocorticotrophs, and thyrotrophs. Nongranulated follicular cells and salivary gland rest cells also were present. Indirect immunoperoxidase staining with monospecific antisera to anterior pituitary hormones revealed abundant prolactin-containing cells, which comprised more than 50% of all chromophilic cells, as well as numerous cells that contained growth hormone and thyroid-stimulating hormone. Gonadotrophic cells could not be demonstrated by either tinctorial stains or immunostaining.  相似文献   

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A novel monocyte chemotactic factor, a cross-linked homodimer of S19 ribosomal protein (RP S19) was initially isolated from a rheumatoid arthritis synovial lesion. The RP S19 dimer causes the monocyte specific chemotaxis in vitro and the monocyte predominant infiltration in vivo, via its agonistic and antagonistic effects on the C5a receptors of monocytes and polymorphonuclear leukocytes, respectively. The agonistic effect is attributed to the similarity of regional structures between RP S19 and C5a, the complement C5-derived leukocyte chemotactic factor, although overall homology of the amino acid sequence between these molecules is only 4%. The antagonistic effect depends upon the C-terminal portion of RP S19. The RP S19 dimer is produced and released by apoptotic cells, and this dimer recruits monocytes from the circulation to the apoptotic lesion. The infiltrated monocytes/macrophages engulf the apoptotic cells, translocate to regional lymph nodes via lymphatics and present the antigenic information of the apoptotic cells to the T cell repertoire. In this manner, the apoptotic cell clearance system connects to the acquired immune system. The innate and acquired immune mechanisms, mediated by the RP S19 dimer, participate in the pathology of inveterate chronic inflammation such as rheumatoid arthritis.  相似文献   

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苏英豪  杨光霖 《中华病理学杂志》1994,23(6):338-340,T067
采用光间和电镜酶组织化学技术对胃癌和胃良性病变碱性磷酸酶同工酶的活性和分布进行观察,结果表明:Nagao,Regan和Kasahara同工酶在正常胃粘膜和非癌病变中均无表达,可作为胃癌的肿瘤标志;肠化上皮仅表达小肠型ALP,是肠化上皮分化成熟的标志。从ALP同工酶基因表达角度来看,两次突变假说和隐性基因突变假和说适用于胃癌。  相似文献   

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Hehlmann  R.  Schetters  H.  Kreeb  G.  Erfle  V.  Schmidt  J.  Luz  A. 《Journal of molecular medicine (Berlin, Germany)》1983,61(24):1217-1231
Journal of Molecular Medicine - The detection and characterization of oncogenes via RNA tumor viruses (or retroviruses) and the recognition of their location at breakpoints of chromosomal...  相似文献   

14.
The distribution of lysozyme in normal and pathological human gastric and colonic mucosa was studied by light and electron microscopic immunocytochemical techniques and compared with histological and histochemical features. Lysozyme was localized in pyloric glandular epithelial cells, mucous neck cells of fundic glands, Paneth cells and some crypt cells of the mature colonic mucosa. In addition, lysozyme was detected in a large spectrum of "immature" or "regenerative" epithelium: neck cells of the gastric regenerative zone, undifferentiated columnar cells of surface and hyperplastic interfoveolar crests of the stomach, regenerative cells in a healed gastric ulcer, some goblet cells in incomplete intestinal metaplasia, cells of the regenerative zone at the bottom of colonic crypts and, finally, fetal intestinal epithelium. Electron microscopically, we localized lysozyme in the central core of mucous granules in the pyloric gastric glandular epithelium and in the dense mucous granules in gastric mucous neck cells. Lysozyme was also detected in some immature mucin-producing cells of the gastric regenerative zone and in the rough endoplasmic reticulum of surface hyperplastic columnar gastric cells. At the electron microscopic level, a peculiar correlation between the immunopattern of lysozyme and the morphology of mucous granules has been postulated. All our data support and extend the view that the presence of lysozyme may be related to cell immaturity as well as to a regenerative state of the cell. Finally, the lysozyme distribution and its relation to mucosubstances in gastric and colonic carcinoma suggest that lysozyme should not be considered an exclusive marker of cells of gastric derivation.  相似文献   

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Administration of aminoglycoside antibiotics is frequently associated with tubular necrosis which can eventually lead to renal dysfunction. Previously, we have shown that renal tissue injury due to aminoglycoside nephrotoxicity elicits a process of tissue repair characterized by stimulation of cell proliferation. The present study was undertaken to examine both quantitatively and qualitatively the cell proliferation associated with renal tissue repair. Female Sprague-Dawley rats (180-200 g body weight) were treated ip for 10 days with various doses of tobramycin (10, 20, or 50 mg/kg twice daily). Each animal received 200 microCi [3H]thymidine 1 hr before sacrifice to evaluate the extent of cell proliferation in renal cortex. The rate of DNA synthesis in renal cortex was estimated by measuring the specific radioactivity of the nucleic acid. The frequency and localization of S-phase cells in cortex tissue were determined on paraffin and plastic tissue sections processed for histoautoradiography. In addition, the ultrastructure of proliferating cells was characterized by electron microscopic examination of consecutive ultrathin sections. An excellent correlation (r = 0.993) was found between the rate of DNA synthesis and the frequency of S-phase cells evaluated in rats receiving various doses of tobramycin. The stimulation of cell proliferation involved mostly proximal tubular cells and interstitial cells. The latter cells had the ultrastructural appearance of fibroblasts at various stages of differentiation. Similarly, S-phase cells in proximal tubules were either fully differentiated epithelial cells or immature elements. Taken together, the present experimental data illustrate the capacity of the kidney to trigger complex tissue reactions in response to nephrotoxic injury.  相似文献   

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We have investigated the distribution of type VI collagen in normal human liver obtained from cadaveric renal transplant donors, using a peroxidase-antiperoxidase method for light microscopic visualization, and an immunogold labelling method for ultrastructural localization. The distribution was compared with that of the more abundant interstitial collagen type III, using antibodies to amino terminal procollagen type III. Staining for type VI collagen was identified in Glisson's capsule, in portal tract stroma and within the space of Disse. Perisinusoidal staining showed intra-acinar heterogeneity with the intensity in acinar zones 2 and 3 being greater than in zone 1. Type III collagen was also found in the space of Disse although no significant intra-acinar variation in staining intensity was noted. Immuno-gold labelling for type VI collagen was demonstrated on amorphous or microfilamentous material lying between, and occasionally appearing to interconnect, cross-striated collagen fibrils, whereas labelling for amino terminal procollagen type III was exclusively on fibrils. Intracellular staining for type VI collagen was noted in perisinusoidal (lto) cells. These results confirm that type VI collagen is a ubiquitous constituent of the normal hepatic extracellular matrix and suggest that it may be synthesized by perisinusoidal (lto) cells. The distribution of type VI collagen was also studied in biopsy material from patients with different histological stages of primary biliary cirrhosis. Intense staining was noted around proliferating bile ductules within developing fibrous septa and in established septa of cirrhotic liver. These observations indicate that this 'minor' matrix component may play an important role in hepatic fibrogenesis.  相似文献   

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In order to clarify morphologic changes associated with cyclosporine (CS) nephrotoxicity, CS in ethyl alcohol at 25 mg/kg/day i.p. was administered to male Sprague-Dawley rats for periods of 1 to 8 weeks. Mean systolic BP was slightly increased in the CS group at 4 weeks (p < 0.05), but there was no difference compared to a control group at 8 weeks. Blood urea nitrogen was significantly elevated at 4 weeks and continued to rise (p < 0.005), whereas serum creatinine was elevated at 8 weeks. Microscopic examination of the kidneys from CS-treated rats at one week revealed cytoplasmic vacuolization in all segments of the proximal tubules, tubular inclusion bodies, and peritubular capillary congestion. Ultrastructurally, some vacuoles were neutral fat droplets, while others appeared as single membrane-bound structures due to dilatation of the endoplasmic reticulum. The tubular inclusion bodies were enlarged autolysosomes filled with distorted mitochondrial fragments. At two weeks, tubular regeneration was prominent, in addition to the above mentioned toxic tubulopathy. At four weeks, focal areas of interstitial fibrosis and tubular atrophy associated with cystic dilatation were seen. At 8 weeks, interstitial and intratubular microcalcification were present, in addition to patchy foci of interstitial fibrosis, but vascular lesions were not demonstrated. Although renal tubular changes characterized by vacuolization, inclusion bodies, and microcalcification and interstitial fibrosis are not specific for CS toxicity, these changes are commonly found in both humans and rats at high doses of CS.  相似文献   

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Light and electromicroscopical as well as histochemical investigations were performed on three cases of extraadrenal paragangliomas. They were localized in the carotid body, tympanicum and cauda equina region. Tissue of two cases was cultivated in vitro in nutrient medium TCM 199. The tumours were classified as paragangliomas of the paraganglionic type with typical cell clusters, of the adenomatous and angiomatous type. The enzyme histochemistry showed a very high dehydrogenase activity. Ultrastructurally numerous typical osmiophilic granules could be observed in the cytoplasm of the tumour cells. In tissue culture only a minimal cellular proliferative activity could be detected. The few proliferating cell colonies showed mostly characteristics of epithelial tissue and sometimes a similar behaviour to cells of a ganglioneuroblastoma. The minimal proliferative activity in vitro is in good agreement with the proliferative behaviour of the extraadrenal paragangliomas in vivo.  相似文献   

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Amyloid associated with seven sclerotic and two normal aortic and mitral valves was studied. The sclerotic valve amyloid contained microfibrils with typical random orientation and a fibril width of 9.5-12.5 nm. The amyloid deposits demonstrated permanganate-resistant Congophilia and contained the amino acid tryptophan. Immunofluorescence studies showed P-component in amyloid deposits of 6 of 7 valves, but none of the sclerotic valves contained amyloid fibril proteins of the AL (primary), AA (secondary), AEt (medullary thyroid carcinoma) or ASc1 (senile cardiac) types. Two non-sclerotic valves, removed from a patient with systemic amyloidosis, showed permanganate-sensitive Congophilic amyloid deposits which contained amyloid fibril protein AA.  相似文献   

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