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111.
Nishimura Hiroyuki; Hattori Susumu; Ueda Genjiro; Abe Masaaki; Yang Kwangseok; Nozawa Shingo; Okamoto Hiroshi; Zhang Danqing; Tsurui Hiromichi; Hirose Sachiko; Shirai Toshikazu 《International immunology》1995,7(7):1115-1123
Using two mAb, one specific to the alternative exon 6-dependentepitope of CD45 molecules(JH6.2) and one a natural thymocytotoxicautoantibody (NTA) with an unknown reactive epitope (NTA260),we subdivided splenic CD4+ T cells from 2-month-old BALB/c miceinto five phenotypically distinct subsets. CD45RC+NTA260–(SI) cells were phenotypically analogous to CD4+ T cells predominatingin newborn mice and produced a significant amount of IL-2, butnot so IL-4, IL-10 or IFN- when stimulated with immobilizedanti-CD3 mAb in vitro. They appeared to consist mainly of naiveThP cells. The CD45RC+;NTA260+ (S II) subset also produced IL-2,but not other cytokines; however, the IL-2 levels produced weremuch higher than seen with the S I subset, thereby suggestingthe predominance of further maturated ThP cells. The D45RC–NTA260+(S III) subset mainly produced IL-4, IL-10, IFN- and less IL-2,and contained memory cells that helped the secondary antibodyresponse to a recall antigen, and hence contained Th2 and probablya mixture of Th0 and Th1 cells. The CD45RC–NTA260–(S IV) subset was a poor responder to the immobilized anti-CD3mAb. The CD45RCbrightNTA260dull(S V) subset consisted of a smallnumber of cells that were phenotypically analogous to activatedCD4+ T cells. While an age-associated decrease in the proportionof S I and less markedly in S II and in turn increase in S IIIsubsets of CD4+ T cells occurred in normal BALB/c mice, autoimmunedisease-prone (NZBxNZW)F1 mice showed a marked age-associateddecrease in the proportion of not only S I, II but also IIIsubsets. As aged (NZBxNZW)F1 mice carry CD4+ T helper cellsfor IgG anti-DNA antibody production, such age-associated polarizationto the S IV subset appears to be critical in the pathogeneslsof autoimmune disease in these mice. 相似文献
112.
Shinichiro Ushigome Toshifumi Takakuwa Masaaki Hyga Mamoru Tadokoro Toshihito Shinagawa 《Pathology international》1986,36(7):973-987
The authors attempted to clarify the exact cell components of neurofibroma by immunohistochemical and ultrastructural studies. Materials were randomly selected, 40 cases of neurilemoma and neurofibroma (-tosis) in addition to 2 cases of tumors composed exclusively of perineurial cells and three cases of normal peripheral nerve. The applied markers included antisera of S-100 protein for Schwann cells, blood coagulation factor XIIIa for endoneurial fibroblasts or perineurial cells, and laminin and collagen type IV for the basement membrane. S-100 protein was demonstrated only in normal or neoplastic Schwann cells, but not in perineurial cells. On the other hand, factor XIIIa was often recognized in endoneurial fibroblasts and perineurial cells, but not in Schwann cells. Neurofibroma was basically composed of a mixture of Schwann cells, perineurial cells, and endoneurial fibroblasts, the population of each type of cell differing according to the case and area within a given tumor. Perineurial cell tumor exclusively composed of perineurial cells, though rare, appears to be a definite entity, and its characteristic histological and ultrastructural features were described. 相似文献
113.
Ectopic expression of activated Stat6 induces the expression of Th2-specific cytokines and transcription factors in developing Th1 cells 总被引:17,自引:0,他引:17
Stat6 is critical for IL-4-mediated Th2 cell development, but its molecular mechanism remains unclear. Here we constructed Stat6:ER, a Stat6-estrogen receptor fusion protein that can be activated by 4-hydroxy-tamoxifen, independently of IL-4 and endogenous Stat6. Retrovirus-mediated introduction of Stat6:ER into developing Th1 cells induced Th2-specific cytokines and suppressed IFNgamma production in a 4-HT-dependent manner and in the absence of IL-4. It also induced GATA-3 and c-maf expression and downregulated IL-12Rbeta2 chain expression. Its decreased ability to induce the Th2 phenotype with progressing Th1 cell commitment correlated with a decreased induction of GATA-3 and c-maf. This study indicates that Stat6 functions upstream of GATA-3 and c-Maf to induce Th2 development. 相似文献
114.
H Iwata C Arai Y Koike Y Hirouchi K Kobayashi Y Nomura M Enomoto 《Toxicologic pathology》1990,18(3):373-379
Out of the 365 young laboratory beagle dogs which were used in 17 toxicity bioassays, 15 cases (4.1%) were diagnosed as having congenital heterotopic gastric mucosa of the small intestine. Its incidence in the male dogs (12 cases out of 187) was higher than in the female dogs (3 cases out of 178). Grossly, the lesions were seen as an ulcerous focus of the small intestine, 25 cm to 88 cm proximal to the ileocecal valve. All of the lesions were quite similar histologically and electron microscopically to the normal gastric mucosa, which are composed of the surface mucous cells, chief cells, parietal cells, mucous neck cells and basal granulated cells of the stomach. And consequently, they were considered to be that of a congenital heterotopic tissue in the small intestine. The only morphological characteristic of these lesions different from the regular gastric mucosa was an association with the tubular structure seen in the basal region of these mucosal layers. These cells were considered to be of mucous-secreting cell origin because of secreting type III mucous evident from paradoxical concanavalin A or periodic acid Schiff stains. They seemed to be protecting the surrounding intestinal mucosa from gastric acid. 相似文献
115.
K C Herold D W Lancki D E Dunn K Arai F W Fitch 《European journal of immunology》1986,16(12):1533-1538
To study the regulation of lymphokine production by T lymphocytes, we have characterized the activation of lymphokine genes in T cells by measuring the levels of lymphokine mRNA in cloned murine T lymphocytes after stimulation. Lymphokine mRNA was not detected in cells taken after seven days of maintenance culture. Following stimulation of T helper lymphocytes L2 and AD9.1 with concanavalin A, lymphokine mRNA appeared, reached peak levels and disappeared over a 43-h time period. A single stimulation event resulted in the induction of mRNA for interleukin 2 (IL 2), IL 3 and interferon gamma. Maximal mRNA levels were generally found at 6 h in the T helper lymphocytes, but could occur as late as 18 h. The lymphokine genes were expressed coordinately; however, in these cloned cells, IL 2 mRNA levels appeared to be lower than the other two mRNAs. Lymphokine titers in the supernatant fluids paralleled the appearance of mRNA but IL 2 titers began to fall after 12 h probably because of utilization of this lymphokine by the activated cells. In the cytolytic T lymphocyte, L3, qualitatively similar kinetics were found after stimulation by lectin or a clonotypic antibody with peak mRNA levels occurring later (18 h) with the antibody. These studies indicate a single stimulating event activates the lymphokine genes of T cells in a coordinate manner; the appearance of the lymphokines in supernatant fluids represents de novo synthesis of these proteins but the levels of lymphokines measured in supernatant fluids reflects both production and utilization rates, and exposure to IL 2 at the time of stimulation is not essential for the production of other lymphokines. 相似文献
116.
A case with multiple myeloma in which serum forms gel precipitation upon exposure to air 总被引:1,自引:0,他引:1
Oita T Yamashiro A Sakizono K Etoh M Mizutani F Imoto S Nagai K Kasakura S 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(4):404-409
We present the case of a 69-years-old man who was admitted to hospital with multiple myeloma. IgG-kappa type monoclonal protein was detected in the serum. When we separated the serum obtained from blood sample of the patient and the lid of the collecting tube was opened, the patient's serum became gelled immediately. When the lid of the collecting tube remained closed, the patient's serum did not become gelled even at 4 degrees C. Moreover, the gelled serum of the patient did not resolve at 56 degrees C. Taken together, these results indicated that gel formation of the patient's serum may not be due to cryoglobulin. It was found that the pH of the patient's serum elevated to pH 8.0 quickly after exposed to air. It was also found that the patient's serum, but not the sera of other IgG-kappa multiple myeloma patients, became gelled as soon as PBS of pH 8.0 was added. These results highly suggest that the patient's serum becomes gelled at pH 8.0. However, the isoelectric focusing of isolated precipitation in the patient showed fractions around the pH 8.5-8.7 zone, which was different from the pH at which the precipitation began to form. We think that this may be the first report of a multiple myeloma patient whose serum becomes gelled after exposed to air. 相似文献
117.
Regardless of the side of hemiovariectomy, unilateral lesion placed in the right-side medial anterior hypothalamus suppressed ovarian compensatory hypertrophy, but the lesion made in the left side failed to suppress it. This suggests the presence of a hypothalamic laterality in regulating gonadotropin secretion. 相似文献
118.
I Arai C Usuki-Ito M Muramatsu S Otomo T Shiraishi Y Oomura 《Physiology & behavior》1990,47(1):197-202
The involvement of a feeding-related endogenous sugar acid, 2-buten-4-olide (2-B4O) on central regulation of gastric acid secretion, and its antiulcer effects on several gastric and duodenal experimental ulcer models were investigated in rats. Spontaneous gastric acid secretion was not affected by 2-B4O at doses below 10 mg/kg. The peripheral secretagogue-stimulated gastric secretions were significantly increased by pretreatment with 2-B4O. Gastric acid secretion induced by 2-deoxy-D-glucose (2-DG) was significantly suppressed by pretreatment with 2-B4O at doses between 0.1 and 100 mg/kg. Gastric and duodenal ulcerations induced by cold stress plus indomethacin, restraint and water immersion stress, pylorus ligation or cysteamine were also inhibited by pretreatment with 2-B4O. The results suggest that antiulcer effects of 2-B4O are due to suppression of gastric acid secretion via reduction of activity of the vagus nerve and gastric-related hypothalamic neurons. Thus, 2-B4O may be useful for treatment of gastroduodenal ulcer. 相似文献
119.
The aim of the present study is to demonstrate the cellular basis of 5'-nucleotidase (5'-Nase) activity in the greater omentum of rats. Enzyme histochemistry for 5'-Nase showed that lymphatic vessels in the omentum as well as lymphocytes in the milky spots were positively stained. Electron microscopic observation revealed-5'-Nase activity at the luminal surface of the lymphatic endothelial cells, pinocytotic vesicles in the endothelial cells and the surface of fibroblasts located at the intercellular space of adipose cells. Fibroblasts extended long cytoplasmic processes toward adipose cells and inflammatory cells. These findings suggest that lymphatic endothelial cells as well as fibroblasts in the omentum may play an important role in regulation of metabolism and immune mechanisms in the greater omentum by supplying adenosin. 相似文献
120.
Jojiro Jakada Nozomu Furuta Motoshi Kawahara Shoichi Onodera Yukihiko Oishi Masaaki Kawada Tomolcazu Matsuura Satoshi Hasumura Seishi Nagamori 《Medical Electron Microscopy》1998,31(1):24-30
Primary cell cultures of two human pheochromocytomas (PC) that were associated with high serum levels of adrenaline and noradrenaline were developed to study the effects of nerve growth factor (NGF) and dexamethasone on the morphology and function of PC cells in vitro. By phase-contrast microscopy, cultured cells were small and hyperchromatic on the first day of culture; neurite-like processes that extended to other cells developed several days later and were maintained for more than 3 months. NGF (100ng/ml), dexamethasone (10–5M), or NGF + dexamethasone were added to the culture media 2 weeks after the cultured cells had stabilized. Catecholamine concentrations in the medium were maintained at higher levels after addition of NGF, dexamethasone, or NGF + dexamethasone as compared to control cells. In the presence of NGF, extension of neurite-like processes was clearly accelerated, while high levels of dexamethasone inhibited growth of processes. These in vitro studies showed that the addition of NGF or the removal of dexamethasone induces differentiation of adrenal neurons present in pheochromocytomas, suggesting that adrenocortical steroid hormones influence the morphological control of adrenal medullary cells. 相似文献