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71.
Gingival mononuclear cells from chronic inflammatory periodontal tissues produce interleukin (IL)-5 and IL-6 but not IL-2 and IL-4. 总被引:6,自引:1,他引:6
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K. Fujihashi K. W. Beagley Y. Kono W. K. Aicher M. Yamamoto S. DiFabio J. Xu-Amano J. R. McGhee H. Kiyono 《The American journal of pathology》1993,142(4):1239-1250
A unique characteristic of the localized inflammatory tissue in the periodontium (e.g., adult periodontitis [AP]) is the accumulation of IgG (IgG1 > IgG2 > IgG3 > or = IgG4) followed by IgA plasma cells (IgA1 > IgA2). However, the exact molecular mechanisms contributing to these elevated B-cell responses at the local disease site are still unknown. Thus, this study has examined the production of cytokines of importance in B-cell responses, e.g., interleukin (IL)-2, IL-4, IL-5, and IL-6 by gingival mononuclear cells (GMC) isolated from patients in severe stages of AP. These cytokines were assessed at the protein and messenger (m)RNA levels to understand their importance for the observed increased B-cell responses present in these tissues. Among the four cytokines tested by respective cytokine-specific, polymerase chain reaction and dot-blot hybridization, high levels of IL-5- and IL-6-specific mRNA were noted in GMC freshly isolated from AP patients. On the other hand, specific message for IL-2 and IL-4 were not present. Further, the analysis of culture supernatants of GMC also revealed that cells from AP patients spontaneously produced IL-5 and IL-6 but not IL-2 and IL-4. In contrast, when peripheral blood mononuclear cells isolated from the same patients were examined for these cytokines, no detectable levels of mRNA or secreted cytokines were noted. These results showed that GMC from localized inflammatory tissues in severe stages of AP possess a distinct cytokine profile represented by high levels of IL-5 and IL-6 mRNA expression and protein synthesis, whereas IL-2 and IL-4 were not detected. Further, this study supports the concept that AP is a localized inflammatory disease, because GMC from the inflamed tissue actively produce IL-5 and IL-6, whereas peripheral blood mononuclear cells from the same patients do not. 相似文献
72.
Optimizing oral vaccines: induction of systemic and mucosal B-cell and antibody responses to tetanus toxoid by use of cholera toxin as an adjuvant. 总被引:13,自引:7,他引:13
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R J Jackson K Fujihashi J Xu-Amano H Kiyono C O Elson J R McGhee 《Infection and immunity》1993,61(10):4272-4279
Cholera toxin (CT) is an effective mucosal antigen and acts as an adjuvant when given orally with various antigens; however, few studies have compared the levels of antibody responses to CT and coadministered protein in systemic and mucosal tissues. In this study, we used tetanus toxoid (TT) for assessment of immune responses. Time course and dose-response studies established that 250 micrograms of TT given orally with 10 micrograms of CT three times at weekly intervals induced high serum and gastrointestinal tract anti-TT and anti-CT antibody responses. Oral immunization with TT alone induced no detectable mucosal immunoglobulin A (IgA) antibodies in fecal extracts and only weak serum IgG anti-TT responses. The coadministration of CT and TT induced peak serum IgG anti-TT responses following two oral doses that remained constant after the third oral immunization, while optimal mucosal IgA responses were seen after the third oral immunization. The serum anti-TT response obtained with CT and TT proved protective against TT challenge (100 minimum lethal doses), whereas mice orally given CT or TT alone died. Antigen-specific B-cell responses were assessed with an isotype-specific Elispot assay of isolated lymphoid cells from the spleen, Peyer's patches, and the small intestinal lamina propria. Interestingly, approximately fourfold-higher numbers of IgA anti-CT than of anti-TT antibody-producing (spot-forming) cells occurred in lymphocytes from the lamina propria of mice orally immunized with both TT and CT. The adjuvant CT did not induce polyclonal B-cell responses in mice given CT by the oral route, since no significant differences in total numbers of B cells producing IgA, IgG, or IgM were found compared with the numbers in mice given TT alone. The results clearly indicate that serum and mucosal antibody responses develop with different kinetics and that protective TT-specific antibody responses are generated in the systemic compartment when TT is administered with CT via the oral route. 相似文献
73.
Expression of recombinant enterotoxigenic Escherichia coli colonization factor antigen I by Salmonella typhimurium elicits a biphasic T helper cell response
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Pascual DW Hone DM Hall S van Ginkel FW Yamamoto M Walters N Fujihashi K Powell RJ Wu S Vancott JL Kiyono H McGhee JR 《Infection and immunity》1999,67(12):6249-6256
Protective immunity to enterotoxigenic Escherichia coli (ETEC) is antibody (Ab) dependent; however, oral immunization with purified ETEC fimbriae fails to elicit protective immunity as a consequence of antigenic alteration by the gastrointestinal (GI) tract. Unless unaltered ETEC fimbriae can reach the inductive lymphoid tissues of the GI tract, immunity to ETEC cannot be induced. To produce immunity, live vectors, such as Salmonella typhimurium, can effectively target passenger antigens to the inductive lymphoid tissues of the GI tract. By convention, oral immunizations with Salmonella vectors induce CD4(+) T helper (Th) cell responses by gamma interferon (IFN-gamma)-dominated pathways both to the vector and passenger antigen, resulting in serum immunoglobulin G2a (IgG2a) and modest mucosal IgA Ab responses. In the present study, mice orally immunized with a Salmonella vector engineered to stably express ETEC colonization factor antigen I (CFA/I) showed initially elevated serum IgG1 and mucosal IgA anti-CFA/I Ab responses. As expected, mice orally immunized with an E. coli-CFA/I construct elicited poor anti-CFA/I Ab responses. In fact, the addition of cholera toxin during oral E. coli-CFA/I immunization failed to greatly enhance mucosal IgA Ab responses. Seven days after immunization with the Salmonella-CFA/I construct, cytokine-specific ELISPOT showed induction of predominant Th2-type responses in both mucosal and systemic immune compartments supporting the early IgG1 and IgA anti-CFA/I Abs. By 4 weeks, the Th cell response became Th1 cell dominant from the earlier Th2-type responses, as evidenced by increased mucosal and systemic IFN-gamma-producing T cells and a concomitant elevation of serum IgG2a Ab responses. This biphasic response offers an alternative strategy for directing Salmonella vector-induced host immunity along a Th2 cell-dependent pathway, allowing for early promotion of mucosal and systemic Abs. 相似文献
74.
75.
Tadashi Yasuda Hirokazu Imai Yasushi Nakamoto Akira B. Miura Shiegki Inomata 《Virchows Archiv : an international journal of pathology》1992,421(4):297-303
Summary The pathogenesis of the nodular lesion in diabetic glomerulosclerosis is described in association with fibrils. Thirteen diabetic patients with glomerular nodular lesions and 9 diabetics without the nodules were examined by electron microscopy using periodic acid-thio-carbohydrazide-silver proteinate staining. In cases of nodular glomerulosclerosis, abundant fibrillar structures mixed with electron-dense material were detected within the nodule and the mesangial matrix. They were also occasionally observed along the subendothelial space of the glomerular capillary walls. On the cross-section, these fibrils, including the lucent periphery, were 34 nm wide. Immunohistologically, collagen V and collagen VI were detected in nodular lesions. In contrast, in cases of the diffuse type of glomerulosclerosis, the widened mesangium was composed of dense material, which resembled the original mesangial matrix. The above fibrils were not detected in the mesangium. These findings suggest that the accumulation of the peculiar fibrils in the glomerular mesangium is a major pathogenic factor in the formation of Kimmelstiel-Wilson nodules. 相似文献
76.
An Epstein-Barr virus-producer line Akata: Establishment of the cell line and analysis of viral DNA 总被引:10,自引:0,他引:10
Kenzo Takada Kenichi Horinouchi Yasushi Ono Takao Aya Toyoro Osato Motoo Takahashi Shinichi Hayasaka 《Virus genes》1991,5(2):147-156
An Epstein-Barr virus (EBV)-producer line, designated Akata, was established from a Japanese patient with Burkitt's lymphoma. The Akata line possessed the Burkitt's-type chromosome translocation, t(8q-; 14q+), and was derived from the tumor cell. Akata cells produced a large quantity of transforming virus upon treatment of cells with anti-immunoglobulin antibodies (Takada, 1984). Southern blot analysis of viral DNA indicated that the Akata EBV is nondefective and more representative of wild-type viruses. Akata cells should be useful as a source of EBV. 相似文献
77.
Kajihara S Tomita S Kondo Y Arakawa A Okamura S Tomita T Yoshida Y Takanashi Y 《Brain topography》2000,12(4):283-292
The purpose of this paper is to propose a new algorithm for the analysis of biomagnetic field data obtained from magnetoencephalography (MEG) measurements. This new method overcomes two major problems faced by the current method of data analysis. The first problem is the need to determine the number of sites of brain activity before calculations can be performed. The second problem is inability of the analysis to provide any information regarding the volume of the brain activity. The new data analysis method, called the Moving Mesh Method (MMM), is capable of analyzing MEG data without the need to determine the number of sources beforehand. In addition, the MMM determines the location of brain activity as a three dimensional volume, instead of as a point source of activity. The MMM uses an iterative method of calculating the position of the sources to achieve greater accuracy, and a regularized g-inverse matrix to stabilize its solution. The feasibility of the MMM was examined by two methods. First, a computer simulation was used to confirm the MMM's capability to analyzing MEG data. In the second experiment, the MMM was applied to analyze somatosensory evoked fields obtained using a new imaging system (Shimadzu Biomagnetic Imaging System, Model-100). From the interpretation of the results, we have concluded that the MMM is a feasible method of biomagnetic data analysis. 相似文献
78.
Shigeo Aizawa Masafumi Suzuki Yasushi Kikuchi Takashi Nikaido Kenji Matsumoto 《Pathology international》1987,37(7):947-954
Seven metastasizing small renal cell carcinomas smaller than 30 mm in the greatest diameter were clinicopathologically studied for a better understanding of their characteristic features as compared to those of small tumors without metastases. Grayish-white infiltrating tumors in gross appearance and alveolar or solid microscopic structure consisting of granular or spindle cells and of atypical nuclei were suggestive of having metastases. Two tumors which had positive reactions to the lower nephron markers such as SB A, PNA, and/or DBA were considered to be of lower nephron origin and displayed poor prognosis. ACTA PATHOL. JPN. 37: 947–954, 1987. 相似文献
79.
Polo-like kinase 1 expression in medullary carcinoma of the thyroid: its relationship with clinicopathological features. 总被引:3,自引:0,他引:3
Yasuhiro Ito Yasushi Nakamura Hiroshi Yoshida Chisato Tomoda Takashi Uruno Yuuki Takamura Akihiro Miya Kaoru Kobayashi Fumio Matsuzuka Kanji Kuma Kennichi Kakudo Akira Miyauchi 《Pathobiology》2005,72(4):186-190
OBJECTIVE: Polo-like kinase 1 (PLK1) is one of the serine-threonine kinases that contributes to cell mitosis and is regarded as a marker of cellular proliferation. However, its protein expression in human carcinoma has not been studied in depth. In this study, we investigated PLK1 expression in medullary thyroid carcinoma by means of immunohistochemistry. METHODS: We immunohistochemically investigated PLK1 expression in 67 cases of medullary thyroid carcinoma. RESULTS: The PLK1 expression level was elevated in 43 of the 67 cases (64.1%). Furthermore, the expression level was directly linked to lymph node metastasis, advanced stage and male sex. All patients who were negative for PLK1 expression are currently alive without tumor recurrence, while 6 of the 43 PLK1-positive patients showed recurrence and 3 have already died of this disease. CONCLUSIONS: These findings suggest that PLK1 expression significantly reflects aggressive characteristics of medullary thyroid carcinoma. 相似文献
80.