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51.
Mariana Villarroel Dorrego Paul M. Speight A. William Barrett 《Journal of oral pathology & medicine》2006,35(5):268-273
BACKGROUND: CD40 has a role in the regulation of immune responses, cell proliferation and migration, and apoptosis. Little is known of its distribution in oral mucosal pathology. METHODS: Oral keratinocyte lines were tested for CD40 protein by Western blotting. Immunohistochemistry was used to stain paraffin sections of oral mucosa in health and in inflammatory, reactive, dysplastic and malignant disease. RESULTS: Western blotting confirmed the presence of CD40 in oral keratinocytes. CD40 was generally expressed by keratinocytes in the basal layer, with variable parabasal expression. Langerhans cells also stained positively. Expression was lost in nine of 33 (27%) epithelial dysplasias, seven of which were severe. Eighty-one percent of well, 69% of moderately and 50% of poorly differentiated oral squamous cell carcinomas (OSCC) expressed CD40. Overall, 45 of 65 (69%) OSCC were positive. The pattern of expression was unrelated to tumour differentiation. CONCLUSION: CD40 expression by basal and parabasal oral keratinocytes is physiological. Expression is lost in approximately one-third of oral epithelial dysplasias and OSCC. The significance of such loss remains unknown, but may be related to immunological or other abnormalities of keratinocyte homeostasis. 相似文献
52.
Objective To observe the effect of electro-acupuncture combined with early rehabilitation on the motor function and expressions of the adhesion molecules CD11b and CD18 in the polymorphonuclear leucocytes (PMN) and monocytes and serum tumor necrosis factor-α (TNF-α) levels in patients with acute cerebral infarction (ACI). Methods A total of 165 ACI patients were randomly divided into control group (group A, n=50), conventional rehabilitation group (group B, n=50) and comprehensive rehabilitation group (group C, n=65). The expressions of CD11b and CD18 in the PMN and monocytes and serum TNF-α levels were determined before and at 1, 2, and 4 weeks after the treatment. Thirty-two healthy subjects were also recruited as the normal control group (group N). The neurological function of the subjects was evaluated by modified Edinburgh-Scandinavia stroke scale (MESSS) and Fugi-Meyer Assessment (FMA), and their activity of daily living (ADL) was assessed using Barthel index (BI). Results The CD11b/CD18 expression in the PMN and MN and serum TNF-α level in groups A, B and C were significantly higher than those in group N before and 1 week after the treatment (P<0.05). CD11b/CD18 expression and serum TNF-α level were significantly lower in groups B and C than in the group A at 1 week after the treatment, and significantly lower in group C than in group B (P<0.05). At 2 weeks of treatment, CD11b/CD18 and TNF-α were significantly lower in groups B and C than in the group A, being the lowest in group C (P<0.05). The scores of mESSS in both groups B and C were lower than that in group A, and the scores were lower in group C than in group B. Group C showed higher FMA scores than group B, both having higher scores than group A. At 4 weeks of treatment, the mESSS scores were significantly lower, hut the FMA and ADL score significantly higher in groups B and C than in the control group (P<0.05), and the differences were more obvious in group C. Groups B and C had greater effective rate than group A (P<0.05), and the rate was the highest in group C (P<0.05). Conclusion Electro-acupuncture combined with early rehabilitation promotes the recovery of motor function in ACI patients probably by regulating the expressions of the adhesion molecules CD11b and CD18 on the PMN and monocytes and the serum levels of TNF-α. 相似文献
53.
E-钙黏附蛋白、CD44v6在卵巢上皮性肿瘤及卵巢癌转移灶中的表达 总被引:2,自引:2,他引:0
目的:在基因表达水平上研究黏附分子(E-cadherin,CD44v6)与卵巢癌转移的关系。方法:用免疫组化S-P法,选取1997~2002年间石蜡包埋的卵巢上皮性肿瘤组织块107块,其中良性上皮性肿瘤30例,交界瘤13例,恶性34例(Ⅰ、Ⅱ期4例,Ⅲ、Ⅳ期30例),对30例恶性晚期(Ⅲ、Ⅳ期)病例选取对应的大网膜转移组织。结果:30例良性上皮性肿瘤组织中,E-钙黏附蛋白100%强阳性表达,CD44v6100%阴性。13例交界瘤中,E-钙黏附蛋白有11例(84.6%)强阳性,CD44v6有1例弱阳性表达。34例恶性上皮性肿瘤中,E-钙黏附素有24例(70.6%)阳性表达,CD44v6有11例(32.4%)阳性表达。二指标在良性上皮性肿瘤与卵巢癌之间的阳性表达有显著性差异(P=0.001,P=0.000)。二指标在原发灶和大网膜转移灶之间表达无显著差别(P=1.000,P=1.000)。结论:E-cadherin及CD44v6在上皮性卵巢肿瘤中的表达呈相反趋势,E-cadherin及CD44v6与卵巢癌组织学分级及预后无明显相关性。 相似文献
54.
Jing‐Long Huang Liang‐Shiou Ou Ching‐Hsiung Tsao Li‐Chen Chen Ming‐Ling Kuo 《Pediatric allergy and immunology》2002,13(6):426-433
T lymphocytes play a fundamental role in the initiation and regulation of chronic inflammatory responses in patients with asthma. CD69 is an early marker of T‐cell activation. The levels of intercellular adhesion molecule‐1 (ICAM‐1, CD54) and L ‐selectin have been reported to increase in patients with allergic diseases and asthma. The present study was therefore undertaken to investigate the expression of CD69, CD54, and L ‐selectin by T lymphocytes of children with asthma, before and after immunotherapy. Eighteen children newly diagnosed with asthma, 11 good and nine poor responders to immunotherapy, and 16 normal subjects, were enrolled in this study. The percentages of CD69+, CD54+, and CD62L+ cells in T lymphocytes were measured by using flow cytometry. The levels of CD69, CD54, and CD62L in serum and culture supernatants were determined by using enzyme‐linked immunosorbent assay (ELISA). The expression of CD69 and CD54 on CD3+ T lymphocytes was significantly higher in children with asthma than in control patients. All the patient groups expressed (spontaneously and following stimulation with phorbol myristate acetate and ionomycin together with mite‐extract proteins) greater amounts of CD69 and CD54 than did control subjects. With long‐term immunotherapy, the percentages of CD69+ and CD54+ T lymphocytes were significantly lower in patients with a good response to immunotherapy. Our results also showed significantly lower serum L ‐selectin levels following immunotherapy. In conclusion, successful immunotherapy resulted in decreased expression and production of CD69 and CD54. These results may explain, in part, the clinical efficacy of immunotherapy. 相似文献
55.
Monocyte adhesion molecule expression in interstitial inflammation in patients with renal failure. 总被引:2,自引:0,他引:2
Elham Dadfar Joachim Lundahl Stefan H Jacobson 《Nephrology, dialysis, transplantation》2004,19(3):614-622
BACKGROUND: Patients with renal failure have an increased susceptibility to infections. We therefore studied the recruitment of monocytes and their expression of adhesion molecules CD11b and CD62L at the site of interstitial inflammation in patients with renal failure. Furthermore, we studied if the capacity of monocytes to up-regulate CD11b in interstitial inflammation was determined by the interstitial concentration of chemotactic factors. METHODS: Three intensities of interstitial inflammation (0, intermediate and intense) were established in skin blister chambers. Leukocyte count, CD11b/CD62L expression, monocyte chemotactic protein-1 (MCP-1) and blister activity in terms of CD11b mobilization were determined. RESULTS: The CD62L expression on monocytes was lower in the peripheral circulation in patients with renal failure compared with healthy subjects (P<0.005 and P<0.001). At the site of interstitial inflammation patients had a higher expression of CD62L (intermediate, P<0.05; intense, P<0.005). Furthermore, monocytes from patients had an impaired capacity to mobilize CD11b both in the peripheral circulation (P<0.005) and at the intermediate and intense sites of interstitial inflammation (P<0.005 and P<0.001, respectively) compared with cells collected from healthy subjects. We incubated monocytes in blister exudates, in order to explore whether this phenomenon is caused by cellular factors and/or to the interstitial concentration of chemotactic mediators. The expression of CD11b on monocytes from healthy blood donors incubated in blister exudates from either patients or healthy subjects in vitro was similar. The interstitial concentration of MCP-1 at the site of intermediate inflammation was significantly lower in patients with renal failure compared with the corresponding blister exudate collected from healthy subjects (P<0.05), but no differences were observed at the site of intense inflammation. Furthermore, neutralizing the action of MCP-1 in blister exudates with monoclonal antibodies did not have any impact on monocyte CD11b expression following incubation in blister exudates. CONCLUSION: These studies indicate that the impaired capacity of monocytes to mobilize CD11b at the site of inflammation in patients with renal failure is more dependent on constitutive cellular factors than the concentration of CD11b mobilizing factors in the interstitium. 相似文献
56.
57.
Margaret J. Tango Evelyn Safaris Margarita Romanella Atousa Aminian Marina Katerelos Christine Somerwille RIek G. Tearle Martin J. Pearse Anthony J.E d'Apice 《Xenotransplantation》1997,4(1):25-33
Abstract: Transgenic expression of the human complement regulatory molecule CD59 in mice and genetic deletion of the major xenoantigen galactose α 1,3 galactose (Gal KO) each resulted in partial protection of spleen cells from lysis by human serum. These protective effects were additive when the two genetic modifications were combined. However, when the effects of these genetic modifications were examined in an ex vivo model in which mouse hearts were perfused with human plasma, it was Gal KO which was the modification which determined protection. CD59 expression alone was not protective and CD59 expression in combination with Gal knockout did not result in a significant additional increase in protection over and above that provided by Gal knockout alone. The likely explanation for this discrepancy between the in vitro and ex vivo data is that the H2-Kb promoter used to drive CD59 expression results I in substantially less expression on endothelium than on spleen cells. 相似文献
58.
Eric Vivier Antonio J. da Silva Melissa Ackerly Herbert Levine Christopher E. Rudd Paul Anderson 《European journal of immunology》1993,23(8):1872-1876
The CD16: ζ: γ receptor complex allows natural killer (NK) cells to recognize and eliminate antibody-coated target cells. Whereas the ectodomain of CD16 is the receptor for Fcγ domains of immunoglobulins, disulfide-linked homo- and heterodimers composed of ζ and γ are required for the cell surface expression, and signal transduction properties of the complex. Engagement of CD16 activates the tyrosine kinase pathway, which induces the tyrosine phosphorylation of several substrates, including the ζ subunit and the phospholipase C γ-1 and γ-2 isoforms. Here we show that CD 16 stimulation of either peripheral blood NK cells, leukemic NK cells, or Jurkat transformants expressing a CD16:ζ:γ receptor complex, results in the tyrosine phosphorylation of a 70 kDa ζ-associated protein (pp70). Similarly, a 70-kDa ζ-associated phosphoprotein in T cells has been shown to be a tyrosine kinase (ZAP-70). Peptide mapping analysis indicates that the 70-kDa ζ-associated phosphoproteins from T cells and NK cells are structurally indistinguishable. We conclude that the CD16:ζ:γ complex may use a ZAP-70-related non-receptor tyrosine kinase, in the CD16 signaling cascade leading to NK cell activation. 相似文献
59.
Soluble CD30 in pediatric patients with atopic dermatitis 总被引:9,自引:1,他引:8
Atopic dermatitis (AD) is a chronic, inflammatory skin disease in which a pathogenetic role of Th2 cells has been supposed. This study investigated the presence of soluble CD30 (sCD30), an activation marker of T-cell clones able to produce Th2-type cytokines, in sera from pediatric patients affected by AD ( n =25) with no symptoms of asthma or rhinitis. The severity of the disease was graded by both the SCORAD and Costa et al. clinical scoring systems. Serum levels of sCD30 were significantly higher in patients with AD in respect to both normal donors ( n =20) and urticaria patients ( n = 10), and a positive correlation between serum sCD30 and clinical score was found ( r =0.508; P =0.01) when AD patients were evaluated by Costa et al.'s method. Furthermore, a significant association ( r -=0.443; P =0.027) between sCD30 and serum levels of the soluble interleukin (IL)-2 receptor (sIL-2R) was observed in AD. The presence of high amounts of sCD30 in atopic patients seems to confirm the role of this molecule as an activation marker useful for in vivo evaluation of a Th2 immune response, and the correlation observed with both clinical score and sIL-2R levels indicates the role of sCD30 as an additional marker of disease activity in pediatric patients with AD. 相似文献
60.
A. V. Filatov S. A. Prokof'ev V. V. Shcherbukhin 《Bulletin of experimental biology and medicine》1992,114(5):1656-1659
Institute of Immunology, Ministry of Health of Russian. (Presented by Academician of the Russian Academy of Medical Sciences R. V. Petrov.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 11, pp. 506–508, November, 1992. 相似文献