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31.
Enhanced Immunological Memory Responses to Listeria monocytogenes in Rodents, as Measured by Delayed-Type Hypersensitivity (DTH), Adoptive Transfer of DTH, and Protective Immunity, following Lactobacillus casei Shirota Ingestion 下载免费PDF全文
R. de Waard E. Claassen G. C. A. M. Bokken B. Buiting J. Garssen J. G. Vos 《Clinical and Vaccine Immunology : CVI》2003,10(1):59-65
We have investigated the effect of orally administered Lactobacillus casei Shirota (L. casei) on immunological memory, as measured by delayed-type hypersensitivity (DTH) and acquired cellular resistance (ACR). The studies were performed in animal models in which the animals were rendered immune by a primary Listeria monocytogenes infection. It was shown that orally administered viable L. casei, and not heat-killed L. casei, enhanced significantly the antigen-specific DTH at 24 and 48 h in Wistar rats, Brown Norway rats, and BALB/c mice in a time- and dose-dependent fashion. L. casei had to be administered at least 3 days prior to the DTH assay at a daily dose of 109 CFU in order to induce significant effects. Long-term administration of 109 CFU of viable L. casei resulted in enhanced ACR, as demonstrated by reduced L. monocytogenes counts in the spleen and liver and diminished serum alanine aminotransferase activity after reinfection. Enhancement of cell-mediated immunological immune responses by L. casei was further established in an adoptive transfer study. Naïve recipient BALB/c mice, which were infused with nonadherent, immunized spleen cells from L. casei-fed donor BALB/c mice, showed significantly enhanced DTH responses at 24 and 48 h compared to recipient mice which received spleen cells from control donor mice. In conclusion, orally administered L. casei enhanced cell-mediated immunological memory responses. The effects relied on lactobacillus dose and viability as well as timing of supplementation and, further, appeared to be independent of host species or genetic background. 相似文献
32.
Human CTLA-4 is expressed in situ on T lymphocytes in germinal centers, in cutaneous graft-versus-host disease, and in Hodgkin's disease. 总被引:1,自引:0,他引:1 下载免费PDF全文
K. Vandenborre J. Delabie M. A. Boogaerts R. De Vos K. Lorr C. De Wolf-Peeters P. Vandenberghe 《The American journal of pathology》1998,152(4):963-973
Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4, CD152) is a molecule expressed on in vitro activated T cells. CTLA-4 shares important sequence homology with CD28 and binds to the same ligands, CD80 (B7-1) and CD86 (B7-2). CTLA-4 probably functions as a negative regulator of T lymphocyte activation in the mouse, although this remains to be proven for human T lymphocytes. We have developed new monoclonal antibodies against human CTLA-4 and have investigated the in situ expression of CTLA-4 in a wide variety of normal and pathological human tissues expressing CD80 and CD86. As revealed in this study, CTLA-4 is expressed on thymocytes in thymic medulla, on a subset of CD4+ T lymphocytes in germinal centers of follicular hyperplasia, on T cells, mainly CD8+, infiltrating skin affected by graft-versus-host disease, and on T cells, mainly CD4+, infiltrating Hodgkin's disease lesions. In immunoelectron microscopy, CTLA-4 was found on the plasma membrane as well as in the hyaloplasm and cytoplasmic vesicles, in agreement with its pattern of expression on in vitro activated T cells. Interestingly, no or at most scarce expression of CTLA-4 was found in granulomatous lymph nodes, T-cell-mediated inflammatory diseases, or non-Hodgkin's lymphomas, regardless of their expression of CD80 or CD86. Thus, expression of CTLA-4 appears to be induced in selective pathological conditions in vivo. The pathways leading to selective induction of CTLA-4 and its role in the pathophysiology of these conditions need to be further investigated. 相似文献
33.
C Leprevost M Capron C De Vos M Tomassini A Capron 《International archives of allergy and applied immunology》1988,87(1):9-13
The in vivo inhibitory effect of a new antiallergic, anti-H1 drug, cetirizine, on eosinophil attraction at skin sites challenged with various stimuli has been recently suggested. In the present work, we confirmed that this molecule, at therapeutical concentration, has a potent inhibitory action on eosinophil response to different chemoattractant mediators such as platelet-activating factor (PAF acether) and N-formyl methionyl leucyl phenyl alanyl in vitro. Another anti-H1 drug, polaramine, did not show this effect at the same concentration. These findings suggest that cetirizine in addition to its antihistaminic effect could also play a direct inhibitory effect on eosinophil recruitment. Moreover, cetirizine was not toxic for eosinophils and did not induce degranulation, as shown by the absence of peroxidase release. Comparison between cetirizine and a PAF acether antagonist (BN 52021) suggested that cetirizine did not act by a PAF receptor-blocking activity. 相似文献
34.
Absence of caspase 3 activation in neoplastic cells of nasopharyngeal carcinoma biopsies predicts rapid fatal outcome. 总被引:2,自引:0,他引:2
Joost J Oudejans Ahemd Harijadi Saskia A G M Cillessen Pierre Busson I Bing Tan Danny F Dukers Wim Vos Bambang Hariwiyanto Jaap Middeldorp Chris J L M Meijer 《Modern pathology》2005,18(7):877-885
Poor prognosis in nasopharyngeal carcinoma patients may result from resistance to the apoptosis-inducing effect of radio- and/or chemotherapy. Apoptosis depends on proper activation of caspase 3, resulting in cleavage of key proteins like PARP-1. To investigate whether disruption of the apoptosis pathway results in therapy-resistant tumour cells, we investigated whether absence of caspase 3 activation in tumour biopsies of nasopharyngeal carcinoma patients is related to poor clinical outcome. Moreover, we investigated whether absence of caspase 3 activation is related to loss of procaspase 3 expression or expression of the apoptosis regulators p53, bcl-2 and XIAP. We studied 36 Indonesian nasopharyngeal carcinoma patients without evidence of distant metastases who were treated with curative intent by radiotherapy only. Activation of caspase 3 and expression of the different markers were determined using specific antibodies. Levels of caspase 3 activation were determined by quantifying positively staining tumour cells. Nasopharyngeal carcinoma-derived C15 and C17 tumour cells were used as control. Absence of caspase 3 activation was strongly related to a poor clinical response to radiotherapy and to a higher T and N stage, resulting in a particularly poor clinical outcome with regard to progression-free (P<0.0001) and overall survival time (P<0.0001). Absence of caspase 3 activation was significantly correlated to loss of expression of procaspase 3 (P=0.04). In nasopharyngeal carcinoma patients treated with curative intent, absence of active caspase 3-positive neoplastic cells predicts rapid fatal outcome, and is associated with poor response to radiotherapy and high T and N stage at time of presentation. 相似文献
35.
de Pril R Fischer DF Maat-Schieman ML Hobo B de Vos RA Brunt ER Hol EM Roos RA van Leeuwen FW 《Human molecular genetics》2004,13(16):1803-1813
Polyglutamine diseases are characterized by neuronal intranuclear inclusions (NIIs) of expanded polyglutamine proteins, indicating the failure of protein degradation. UBB(+1), an aberrant form of ubiquitin, is a substrate and inhibitor of the proteasome, and was previously reported to accumulate in Alzheimer disease and other tauopathies. Here, we show accumulation of UBB(+1) in the NIIs and the cytoplasm of neurons in Huntington disease and spinocerebellar ataxia type-3, indicating inhibition of the proteasome by polyglutamine proteins in human brain. We found that UBB(+1) not only increased aggregate formation of expanded polyglutamines in neuronally differentiated cell lines, but also had a synergistic effect on apoptotic cell death due to expanded polyglutamine proteins. These findings implicate UBB(+1) as an aggravating factor in polyglutamine-induced neurodegeneration, and clearly identify an important role for the ubiquitin-proteasome system in polyglutamine diseases. 相似文献
36.
Frints SG Jun L Fryns JP Devriendt K Teulingkx R Van den Berghe L De Vos B Borghgraef M Chelly J Des Portes V Van Bokhoven H Hamel B Ropers HH Kalscheuer V Raynaud M Moraine C Marynen P Froyen G 《American journal of medical genetics. Part A》2003,(3):367-374
We describe a 59-year-old male (patient A059) with moderate to severe mental retardation (MR) and a pericentric inversion of the X-chromosome: inv(X)(p21.1;q22.1). He had short stature, pectus excavatum, general muscle wasting, and facial dysmorphism. Until now, no other patients with similar clinical features have been described in the literature. Molecular analysis of both breakpoints led to the identification of a novel "Nuclear RNA export factor" (NXF) gene cluster on Xq22.1. Within this cluster, the NXF5 gene was interrupted with subsequent loss of gene expression. Hence, mutation analysis of the NXF5 and its neighboring homologue, the NXF2 gene was performed in 45 men with various forms of syndromic X-linked MR (XLMR) and in 70 patients with nonspecific XLMR. In the NXF5 gene four nucleotide changes: one intronic, two silent, and one missense (K23E), were identified. In the NXF2 gene two changes (one intronic and one silent) were found. Although none of these changes were causative mutations, we propose that NXF5 is a good candidate gene for this syndromic form of XLMR, given the suspected role of NXF proteins is within mRNA export/transport in neurons. Therefore, mutation screening of the NXF gene family in phenotypically identical patients is recommended. 相似文献
37.
de Koning F. L. Binkhorst R. A. Vos J. A. van 't Hof M. A. 《European journal of applied physiology》1985,54(1):89-94
Summary The force-velocity curve (FVC) of arm flexion was established in 123 untrained males and 110 untrained females aged from 15 to 36 years, and 48 arm-trained athletes competing in different sport disciplines. The FVC was described by Hill's equation and defined by the parameters: maximal static moment (M0), maximal angular velocity (0), maximal power (P0) and the concavity of the FVC (H). Within the given age range the level of the curve parameters of both untrained men and women was independent of age.On average, H was the same in all three groups. As compared to M0 of the untrained males, M0 of the athletes was 33% higher and M0 of the females was 38% lower; with regard to P0 these differences were +30% and –43% respectively. 0 was the same for trained and untrained males, wherease 0 of the women was 10% lower than 0 of the men. 相似文献
38.
Hypertrophic scar formation is associated with an increased number of epidermal Langerhans cells 总被引:11,自引:0,他引:11
The exact pathogenesis of hypertrophic scar and keloid formation is still unknown and a good therapy to prevent or treat these scars is lacking. Because immunological processes seem to be important in excessive scar formation, immunological cells and parameters were studied in a standardized breast reduction wound-healing model in the present study. Standardized scar samples were taken from infra-mammary breast reduction scars, 3 and 12 months following surgery. The samples were investigated for their number of mast cells, Langerhans cells, T-lymphocytes, and macrophages, and the presence of interleukin-4 (IL-4) and counter-regulating interferon-gamma (gamma-IFN), in relation to the scar's clinical appearance--normal or hypertrophic. In this study, hypertrophic scar formation was significantly associated with an increased number of epidermal Langerhans cells (p=0.0001) and significantly (p<0.05) increased expression of epidermal IL-4. No relationship was found between mast cell, T-lymphocyte and macrophage numbers or gamma-IFN staining and the formation of normal or hypertrophic scars. These results, combined with previous observation of abnormal keratinocyte behaviour in this context, indicate that the epidermal immune barrier plays an important role in the development of hypertrophic scars. 相似文献
39.
Maes M De Vos N Pioli R Demedts P Wauters A Neels H Christophe A 《Journal of affective disorders》2000,58(3):241-246
OBJECTIVE: Major depression is associated with defective antioxidant defenses. Vitamin E is the major fat soluble antioxidant in the body. The aim of the present study is to examine serum vitamin E concentrations in major depressed patients versus normal volunteers. METHOD: Serum vitamin E concentrations were measured in 26 healthy volunteers and 42 major depressed patients by means of HPLC. Since vitamin E is a fat soluble vitamin, and serum vitamin E concentrations are strongly related to these of low-density-lipoprotein cholesterol (LDL-C) and triglycerides, we have adjusted the results for possible differences in these lipids. The numbers of peripheral blood leukocytes were measured. RESULTS: Patients with major depression had significantly lower serum vitamin E concentrations than healthy controls. The area under the ROC (receiver operating characteristics) curve was 83%. There were significant and negative correlations between serum vitamin E and number of total leukocytes and neutrophils. CONCLUSIONS: Major depression is accompanied by significantly lower serum vitamin E concentrations, suggesting lower antioxidant defenses against lipid peroxidation. The results could, in part, explain previous findings, which suggest increased lipid peroxidation in major depression. 相似文献
40.
B lymphocyte differentiation in the rat: production and characterization of monoclonal antibodies to B lineage-associated antigens 总被引:1,自引:0,他引:1
F G Kroese A S Wubbena D Opstelten G J Deenen E H Schwander L De Leij H Vos S Poppema J Volberda P Nieuwenhuis 《European journal of immunology》1987,17(7):921-928
Three mouse monoclonal antibodies (mAb) directed against rat B lineage antigens were produced. The mAb, designated HIS14 (IgG1), HIS22 (IgM) and HIS24 (IgG2b), were characterized for binding to lymphoid and nonlymphoid tissues by immunoperoxidase staining of frozen sections and by (double-) immunofluorescence staining of single cell suspensions from lymphoid organs. HIS14 recognized a pan B cell determinant: it reacted with virtually all cells of each anatomic B cell compartment and with about 95% of surface (s)Ig+ cells in thoracic duct lymph and in suspensions of spleen and lymph nodes. HIS22 and HIS24 detected B lineage-associated antigens expressed by major subpopulations of B cells. HIS22 predominantly stained the lymphocyte corona, but not (or weakly) the germinal centers and splenic marginal zones, whereas HIS24 reacted with both corona and germinal center and not (or weakly) with marginal zone. In accordance with this, substantial proportions of sIg+ cells in spleen cell suspensions did not express HIS22 or HIS24 determinants (20% and 27%, respectively). In bone marrow the vast majority of cytomplasmic mu+ pre-B cells were HIS14+ and HIS24+, and up to one third also HIS22+, indicating an appearance of the determinants early in B lymphocytopoiesis. The antigens recognized by HIS14, HIS22 and HIS24 are lost during the final stage of B cell differentiation: none of the mAb bound to plasma cells. As far as detectable, neither cells of myeloid and erythroid lineages in bone marrow nor thymocytes were stained by HIS14, HIS22, or HIS24. In suspensions of peripheral lymphoid organs (spleen and lymph nodes) but not in thoracic duct lymph, HIS14 and HIS24 labeled a small proportion (12% and 14%, respectively) of Ig- cells. HIS22 did not bind to Ig- peripheral lymphocytes. Reactivity of HIS14, HIS22 and HIS24 with nonlymphoid tissues was virtually absent; HIS22 stained the high endothelial venules in lymph nodes and Peyer's patches. As determined by immunoblotting, the antigenic determinants on lymph node cells recognized by HIS14, HIS22 and HIS24 were present on molecules with an apparent molecular mass of 205 kDa, 210 (and 175) kDa and 205 kDa, respectively, which is similar to the molecular mass of the B cell form of the rat leukocyte common antigen. In addition, the antigens recognized by HIS14, HIS22 and HIS24 co-capped with the leukocyte common antigen. This suggests that each of the three mAb recognize determinants present on the B cell form of the leukocyte common antigen. 相似文献