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1.
The mitogenic activity of the cell walls prepared from Mycobacterium bovis BCG, Nocardia rubra, Corynebacterium diphtheriae PW8, and four species of Propionibacterium, Corynebacterium parvum ATCC 11829, Propionibacterium acnes C7, Propionibacterium granulosum ATCC 25564 and Propionibacterium avidum ATCC 25577, were investigated. These cell walls were active as mitogens on normal spleen cells, anti-θ sera-treated spleen cells, macrophage-depleted spleen cells of C57BL/6J mice and cortisone-treated thymocytes of C57BL/6J mice. It was also shown that these cell walls were mitogenic on spleen cells and macrophage-depleted spleen cells of congenitally athymic (nude) mice. The above results suggest that the cell walls investigated in this study act as mitogens on both thymus-derived lymphocytes (T-cells) and bone marrow-derived lymphocytes (B-cells).  相似文献   

2.
Goldenser J., Marva E., Spira D. T., Gabrielsen A. A. and Jensen J. B. 1985. Mitogenic and antigenic activity of Plasmodium falciparum in primate and rodent lymphocytes. International Journal for Parasitology15: 435–440. Considerable reaction of human leucocytes to a wide range of concentrations of plasmodial preparations derived from in vitro cultures of Plasmodium falciparum was observed. Highest responses were recorded after 6 days in culture. This differed from the response to PHA or CON-A which peak with a narrow range of concentrations after 3 days in culture. Parasitized erythrocytes (PE) or parasites released from PE as well as soluble antigens obtained from the particulate preparations had a pronounced mitogenic activity which was unaffected by heating to 56°C for 1 h. Peripheral lymphocytes from man and monkey but not from rats reacted to P. falciparum preparations. Spleen cells obtained from normal rats did not react towards any P. falciparum preparation. Spleen cells of rats immune to P. berghei, responded to normal human erythrocytes but the response against P. falciparum antigens was much higher, indicating cross-reactivity with genus specific antigens. The combination of experimental procedures using human peripheral and rat spleen lymphocytes is suggested for differentiation between mitogenic and antigenic activity. Heat inactivation of some proteases present in the plasmodial preparations, while retaining mitogenic activity, may enable further purification of the mitogenic factors.  相似文献   

3.
T-Cell antigens that induce the in-vitro interferon-gamma response during Cryptosporidium parvum infection of neonatal calves were identified. A total oocyst extract was separated into a high and a low Mr fraction by a microfiltration technique. Both the high and low Mr fractions evoked an in-vitro interferon-gamma response in naturally infected animals, although strong individual differences between the hosts were observed. Using a complement-mediated technique CD4+ T-cells or WC1+γδ T-cells were depleted, whereupon the remaining lymphocyte cultures were stimulated with the different antigen preparations. It was shown that the in-vitro interferon-gamma response of Cryptosporidium-infected calves is CD4+ T-cell-dependent.  相似文献   

4.
The mitogenic effects on human blood lymphocytes of Helix pomatia A hemagglutinin (HP) were measured by assaying incorporation of [14C]thymidine into cellular DNA. This highly purified lectin binds to human lymphocytes, treated with neuraminidase, but not to untreated lymphocytes. HP, which is hexavalent in its native form, totally failed to induce DNA synthesis in neuraminidase-treated as well as in untreated cells. Divalent HP, prepared by partial reduction and alkylation, and HP insolubilized by coupling to nylon sheets, also lacked mitogenicity. Control experiments indicated that neuraminidase-treated lymphocytes responded well to mitogenic lectins such as PHA. The lack of mitogenicity of HP was in contrast to the effects of soy bean agglutinin (SBA), which resembled HP in regard to carbohydrate specificity and ability to bind to neuraminidase-treated lymphocytes only. SBA was strongly mitogenic for neuraminidase-treated lymphocytes. The mitogenic effects of SBA were not inhibited by including varying doses of HP in the incubation mixtures. The results indicate that binding of lectin to carbohydrate receptors on the lymphocyte surface is not by itself sufficient to trigger DNA-synthesis.  相似文献   

5.
Cryptosporidium parvum can survive exposure to harsh environmental conditions, various disinfectants, and high doses of γ-radiation. Recently, it was found that the expression of thioredoxin peroxidase (CpTPx) in C. parvum increased after a high dose of γ-irradiation to the parasite. CpTPx is a two-cysteine peroxiredoxin that contains cysteines at positions 49 and 170. Recombinant CpTPx fused to an N-terminal hexahistidine sequence, (His)6-CpTPx, exhibited substantial thiol-dependent peroxidase activity that protected plasmid DNA from damage by metal-catalyzed oxidation in vitro. (His)6-CpTPx was used to screen sera from C. parvum-infected mice and humans for antibodies against CpTPx. In Western blots, 10% of the mouse sera and 20% of the human sera reacted with (His)6-CpTPx, suggesting that after infection by C. parvum CpTPx can induce a host-immune reaction but is not a major antigen. Immunolocalization studies revealed that CpTPx is expressed mainly in the cytoplasm of C. parvum at various developmental stages.  相似文献   

6.
Summary The distribution of Corynebacterium parvum labeled with 131iodine or 99mtechnetium was studied in 17 patients with bronchogenic carcinoma. The labeled bacteria were given intravenously or intrapleurally and monitored by whole-body gamma tracking and samples of blood and urine. Even though the rate of physical decay is quite different for 131iodine and 99mtechnetium, the tracking time of labeled bacteria was limited to 24 h after injection for both radioactive isotopes. Technetium labeling was preferred because of greater imaging resolution and less radiation dose to the patient. Following intravenous administration, labeled C. parvum was found predominantly in the liver and spleen, and in a lesser amount in the lung. Radioactivity was confined to the pleural cavity after intrapleural injection. These results suggest the combined intravenous and intrapleural route of adjuvant immunosupportive agents such as C. parvum for operable lung cancer patients.  相似文献   

7.
8.
Křivanec  K.  Otčenášek  M. 《Mycopathologia》1977,60(3):139-144
The study of adiaspiromycosis in 8 species of free living mustelid carnivores (266 specimens) revealed the average intensity of infection to be 41.4%. The highest incidence rate was found in the exoanthropic species Putorius eversmanni (73.1 %) and Martes martes (72.2%) while the lowest was observed in the hemisynanthropic species Putorius putorius (30.6%). The stone marten (Martes foina) is a new, still unknown reservoir host of C. parvum var. crescens, C. parvum for which Putorius eversmanni and Mustela nivalis are new hosts, was also demonstrated in 3 cases. In the present paper, the role of mustelid carnivores in natural foci of adiaspiromycosis is discussed and evaluated. The importance of these predators in the circulation of C. parvum var. crescens is relatively wide. They make possible the liberation of adiaspores from the lungs of their prey — primarily small mammals — into the environment and participate in the spread of infection in both the horizontal and vertical directions. They play a part in the process of distributing of the organism to the vicinity of human dwellings, in the development of new elementary foci, and also act as important reservoir hosts of C. parvum var. crescens.  相似文献   

9.
Summary Systemic and local administration of the bacterium Corynebacterium parvum (more accurately known as Propionibacterium acnes) is reported to exert antitumor action via activated macrophages or short-lived cytotoxic T lymphocytes (CTL), respectively. This study examined the effect of C. parvum treatment on resulting in vitro interleukin levels, which are components in the sequence of events leading to the development of effective CTL. C. parvum administration prevented palpable fibrosarcoma development. This was concomitant with restoration and maintenance of normal interleukin-2 (IL-2) and interleukin-3 (IL-3) levels and prevention of suppressor cell development in mice injected with both tumor cells and vaccine. Our finding of C. parvum-induced maintenance of IL-2 and IL-3 levels and apparent lack of suppressor cell formation lends support to the idea of local C. parvum antitumor action possibly being mediated by CTL arising via the interleukin cascade.  相似文献   

10.
Summary Fischer 344 rats received subcutaneous grafts of syngeneic 13762 mammary adenocarcinoma cells. Thereafter, at 20 days, each animal of a group received either daily (×2) permeating intratumor injections of killed Corynebacterium parvum (1.0 mg) saline, and weekly (×4) intravenous (i.v.) or intraperitoneal (i.p.) C. parvum or saline. In addition, a group each (4 groups) of rats were treated with surgical extirpation of the growing tumor nodule and i.v. and i.p. C. parvum or saline administered at weekly (×4) intervals. The results revealed that following intratumor injection of C. parvum there was rejection of tumor by all animals which exhibited long-term survival for 29 months (intratumor saline: 0% survival). The groups of rats treated with surgical extirpation of the tumor and parenteral administration of C. parvum exhibited 70–75% survival for 20 months (saline treated: 20–35% survival). The surviving animals exhibited tumor-specific protection to subsequent tumor cell challenges. Macrophages separated from the lung, peritoneum, and spleen of rats from the intratumor C. parvum group exhibited respectively, 46.2%, 62.9%, and 29.4% cytotoxicity towards target 13762 tumor cells as measured by 51 Cr release. Similar studies using macrophages from the group treated with surgery and parenteral C. parvum revealed similar tumor cytotoxicity (pulmonary: 49.2%; peritoneal: 65.7%; spleen: 34.4%). The splenic lymphocytes from the intratumor and parenteral C. parvum groups exhibited, respectively, 16.9% and 14.7% 51 Cr release following incubation with target tumor cells.This study was supported in part by Grant No. CA18582-01 from the National Cancer Institute  相似文献   

11.
Summary The influence of immunosuppression or immunostimulation on the growth rate of a lymphatic and of a myeloid murine leukemia has been investigated in syngeneic host-tumour relation. Immunosuppression by chemotherapy or X-rays, induced before transplantation of leukemia cells, did not change the survival time of the animals. Treatment with the immunosuppressive drug cortisone which is not cytostatic for these leukemias, if instituted after the transplantation of malignant cells, enhanced the growth rate of the lymphatic leukemia. Nonspecific stimulation with Corynebacterium parvum induced resistance to a graft of lymphatic leukemia in a majority of the mice, but only slowed the growth rate of myeloid leukemia, without preventing death. Immunosuppressive treatment, given before C. parvum, completely blocked the induction of resistance, and if given after C. parvum, abolished the established resistance to lymphatic leukemia. Thus, the danger of immunosuppression accompanying chemotherapy may lie in its abrogating the protective effects of nonspecific immunostimulation.Abbreviations PFC = plaque-forming-cell - SRBC = sheep red blood cell - cort. = cortisone - cyclo. = cyclophosphamide - L-asp. = L-asparaginase - mtx. = methotrexate - ara C = cytosine arabinoside - C.p. = Corynebacterium parvum  相似文献   

12.
Aim: This study investigates the inactivation of Cryptosporidium parvum using the OH radical and reports the OH radical CT (OH radical concentration × contact time) values for C. parvum inactivation. Methods and Results: Although a wealth of information has demonstrated the efficacy of the microbial inactivation activity of the OH radical, no studies have performed a quantitative estimation of the OH radical for C. parvum inactivation. The CT value of the OH radical required for 2 log C. parvum inactivation was measured with two OH radical‐generating systems, photo/ferrioxalate and photo/TiO2. The OH radical was approx. 104–107‐fold more effective for microbial inactivation than other popular chemical disinfectants such as ozone, chlorine dioxide and free chlorine. Conclusions: The OH radical appears to be suitable for microbial inactivation with a calculated CT value required for 2 log C. parvum inactivation of 9·3 × 10?5 mg min l?1. Significance and Impact of the Study: This study is the first report of an investigation on the role of the OH radical in the photo/ferrioxalate and photo/TiO2 systems and on the OH radical CT required for C. parvum inactivation.  相似文献   

13.
The authors examined the effects of manganese salts on the interaction of the AIDS-related pathogen,Cryptosporidium parvum, with human ileoadenocarcinoma (HCT-8) cells in vitro. Manganese (Mn) inhibited binding ofC. parvum sporozoite membrane antigens to intact, fixed HCT-8 cells in a dose-dependent fashion, whereas Ca++, Mg++, and Zn++ salts had no effect. Manganese was also found to affect sporozoite penetration of live HCT-8 cells, which resulted in a dose-dependent inhibition of parasite development. However, the levels of Mn++ needed in the live cell assays was approx 10-fold greater than in the fixed-cell assays. This inhibition of parasite development was not reversible when Ca++ or Mg++ were used as competitors. Oral supplementation of suckling mice infected withC. parvum with MnSO4 resulted in significant reductions and, in some cases, elimination of intestinally derived oocysts.  相似文献   

14.
《Cellular immunology》1985,90(1):32-40
Human B lymphocytes, purified from the peripheral blood of several different donors can be pooled, frozen, and stored in liquid nitrogen to provide an easy and reproducible source of cells for mitogenic assays. These B cell preparations did not show any reactivity to T cell mitogens, but responded to Staphylococcus aureus Cowan strain 1 (SAC) and anti-IgM antibodies to the same extent as freshly purified B cells. When stimulated with either anti-IgM antibodies or SAC, these B cells became responsive to B cell growth factor (BCGF), allowing a quantitative measurement of this important lymphokine activity. In addition, we have studied the reactivity of frozen B lymphocytes to various combinations of activators. We have confirmed that phorbol myristate acetate (PMA) was a very potent mitogenic agent for preactivated human B cells and shown that bacterial lipopolysaccharide (LPS), although not mitogenic by itself, could synergize with anti-IgM antibodies to yield increased levels of stimulation. Furthermore experiments using the lysosomotropic agent leucine methyl ester showed that the action of LPS on anti-IgM-stimulated B cells did not require the presence of functional monocytes. Neither PMA nor LPS could induce BCGF responsiveness and thus these two compounds can be considered exclusive step 2 activators for human peripheral blood B cells.  相似文献   

15.
It is well known that Corynebacterium parvum activates macrophages to produce tumor necrosis factor (TNF). It is suspected that the activation of macrophages by C. parvum requires T-cell participation. The purpose of this study was to confirm that T cells participate in the activation of macrophages by C. parvum. TNF production in vitro from the spleen cells of BALB/c- + / + mice was abrogated completely by the pre-treatment of spleen cells with anti-Ia antiserum and complement, indicating that Ia+ cells are the source of TNF. TNF production was not elicited at all in BALB/c-nu/nu mice. However, there was an increase in the number of Ia+ cells as well as an increase in the weight of spleen and liver. Supernatant from a culture of spleen cells stimulated with phytohemagglutinin-P (a PHA-induced lymphokine) made it possible for BALB/c-nu/nu mice to produce TNF, associated with an induction of Lyt-1+ cells and Lyt-2+ cells. However, treatment with the lymphokine did not augment the increases of Ia+ cells or liver and spleen weights. These results suggest that increasing the number of Ia+ cells is not sufficient to bring about TNF production; Ia+ cells must also be stimulated by T cells or T-cell lymphokines in order to produce TNF. These results suggest that T cells play an essential role in the activation of Ia+ cells against C. parvum.  相似文献   

16.
The protozoan parasites Giardia duodenalis and Cryptosporidium parvum are common causes of diarrhoea, worldwide. Effective drug treatment is available for G. duodenalis, but with anecdotal evidence of resistance or reduced compliance. There is no effective specific chemotherapeutic intervention for Cryptosporidium. Recently, there has been renewed interest in the antimicrobial properties of berries and their phenolic compounds but little work has been done on their antiparasitic actions. The effect of various preparations of blueberry (Vaccinium myrtillus) extract on G. duodenalis trophozoites and C. parvum oocysts were investigated. Pressed blueberry extract, a polyphenolic-rich blueberry extract, and a commercially produced blueberry drink (Bouvrage) all demonstrated antigiardial activity. The polyphenol-rich blueberry extract reduced trophozoite viability in a dose dependent manner. At 167 μg ml−1, this extract performed as well as all dilutions of pressed blueberry extract and the Bouvrage beverage (9.6 ± 2.8% live trophozoites remaining after 24 h incubation). The lowest dilution of blueberry extract tested (12.5% v/v) contained >167 μg ml−1 of polyphenolic compounds suggesting that polyphenols are responsible for the reduced survival of G. duodenalis trophozoites. The pressed blueberry extract, Bouvrage beverage and the polyphenolic-rich blueberry extract increased the spontaneous excystation of C. parvum oocysts at 37 °C, compared to controls, but only at a dilution of 50% Bouvrage beverage, equivalent to 213 μg ml−1 gallic acid equivalents in the polyphenolic-rich blueberry extract. Above this level, spontaneous excystation is decreased. We conclude that water soluble extracts of blueberries can kill G. duodenalis trophozoites and modify the morphology of G. duodenalis and C. parvum.  相似文献   

17.
Aims: To determine the effect of solar radiation on Cryptosporidium parvum in tap and environmental waters. Methods and Results: Outdoor tank experiments and a cell culture infectivity assay were used to measure solar inactivation of C. parvum oocysts in different waters. Experiments conducted on days with different levels of solar insolation identified rapid inactivation of oocysts in tap water (up to 90% inactivation within the first hour). Increased dissolved organic carbon content in environmental waters decreased solar inactivation. The role of solar ultraviolet (UV) in inactivation was confirmed by long-pass filter experiments, where UV-B was identified as the most germicidal wavelength. Reductions in oocyst infectivity following solar radiation were not related to a loss of excystation capacity. Conclusions: Solar UV can rapidly inactivate C. parvum in environmental waters. Significance and Impact of the Study: This is the first study to assess natural sunlight inactivation of C. parvum oocysts in surface waters and drinking water using an infectivity measure and determines the wavelengths of light responsible for the inactivation. The findings presented here provide valuable information for determining the relative risks associated with Cryptosporidium oocysts in aquatic environments and identify solar radiation as a critical process affecting the oocyst survival in the environment.  相似文献   

18.
Summary Intravenous administration of Corynebacterium parvum (C. parvum) to mice during a primary immune response against tumor alloantigens impairs their ability to generate memory cell-mediated cytotoxicity (CMC) in response to an intraperitoneal rechallenge with the same tumor alloantigens. Decreased CMC was observed in spleen and mesenteric lymph nodes, whereas CMC of lymphoid populations from the peritoneal cavity was merely delayed, reaching comparable levels to those found in control animals by day 5. Serum levels of cytotoxic antibody were unaffected, indicating that C. parvum administered during a primary immune response has selective effects on the cytotoxic memory response.  相似文献   

19.
The chemical and immunological properties of the cell walls prepared from the cells of anaerobic coryneforms, Propionibacterium acnes C7 and Corynebacterium parvum ATCC 11829, were partially investigated. The cell walls prepared from P. acnes C7 and C. parvum ATCC 11829 were composed of fatty acids, polysaccharides consisting glucose, galactose and mannose and mucopeptides consisting mainly of alanine, glutamic acid, a, ε-diaminopimelic acid, glycine, muramic acid and glucosamine. As the fatty acid constituents of the cell wall of P. acnes C7, iso-pentadecanoic acid and iso-heptadecanoic acid were detected as major components. Both cell walls prepared from P. acnes C7 and C. parvum ATCC 11829 showed potent adjuvant activity on the formation of circulating antibody and development of delayed type hypersensitivity in vivo and on the primary immune response to sheep erythrocytes in vitro, however, could not augment helper function of carrier-primed T cells and on the development of cell-mediated cytotoxicity to mastocytoma P815-X2 cells in C57BL/6J mice. It is also shown that the cell walls of P. acnes C7 and C. parvum ATCC 11829 act on mouse spleen cells as mitogen.  相似文献   

20.
Summary The objective of the present investigation was to establish whether a known lymphoreticular-stimulating agent Corynebacterium parvum would augment the established antitumor activity of -difluoromethylornithine in vivo. Furthermore, since C. parvum is known to boost cell mediated cytotoxicity, the effect of DFMO (DL--difluoromethylornithine·HCl·H2O) treatment was evaluated on macrophage and natural killer (NK) cell tumoricidal activity. DFMO administered alone, 1% or 2% in drinking water, inhibited 49.4% or 88.0% of B16 melanoma growth in vivo, respectively. Administration of C. parvum alone, three doses of 300 g each, inhibited tumor growth 57.4%. When administered together, DFMO and C. parvum treatment resulted in 89.8% (1% DFMO) or 97.4% (2% DFMO) inhibition of melanoma growth depending upon the dose of DFMO. C. parvum-treated animals had increased levels of macrophage-mediated tumoricidal activity directed against B16 melanoma cells in vitro, however, NK cell activity was reduced. DFMO treatment alone had no effect on macrophage or NK cell tumoricidal activity. In animals receiving both C. parvum and DFMO treatments macrophage-mediated tumoricidal activity was augmented. These results demonstrate that C. parvum can augment the antitumor activity of DFMO in vivo, possibly through macrophage activation. Furthermore, in contrast to many other cancer chemotherapeutic drugs, DFMO is apparently not immunosuppressive regarding tumoricidal effector cells.  相似文献   

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