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111.
Generation of functional and mature dendritic cells from cord blood and bone marrow CD34+ cells by two-step culture combined with calcium ionophore treatment 总被引:14,自引:0,他引:14
Liu A Takahashi M Narita M Zheng Z Kanazawa N Abe T Nikkuni K Furukawa T Toba K Fuse I Aizawa Y 《Journal of immunological methods》2002,261(1-2):49-63
The object of this study is to explore a culture method to generate a large number of functional and mature dendritic cells (DC) from human CD34+ hematopoietic progenitor cells. In the present study, we used a two-step method combined with calcium ionophore to induce DC from cord blood (CB) or normal human bone marrow (BM) CD34+ progenitor cells. The two-step method consists of 10 days of first step culture for the expansion and proliferation of CD34+ hematopoietic progenitor cells in the presence of SCF, IL-3, IL-6, G-CSF, and 7--11 days of second step culture for the induction of DC in the presence of GM-CSF, IL-4 and TNF-alpha. By the two-step culture, total nucleated cells were increased 208+/-66 (+/-SD, n=13), or 94+/-29 (n=5)-fold in the culture of CB or BM cells, respectively, compared with the number of CD34+ cells at the time of starting culture. Out of the total nucleated cells, 23 +/-10.4% of cells in CB cell culture and 25 +/-5% of cells in the BM cell culture acquired DC characteristic phenotypes, which were marked expressions of CD1a, HLA-DR, co-stimulatory molecules such as CD80, CD40, and adhesion molecule such as CD58. In allogeneic mixed leukocyte reaction (MLR), two-step cultured cells showed potent allo-stimulatory capacity. With this two-step culture, the absolute number of CD1a+ cells that co-expressed HLA-DR, CD80, CD40 and CD58 was enhanced approximately 3 times in CB cell culture and 1.9 times in BM cell culture, compared with the commonly used one-step culture method for the generation of DC from CD34+ cells using SCF, GM-CSF and TNF-alpha. However, on these DC generated in the two-step culture, the expressions of co-stimulatory molecule CD86 and mature DC marker CD83 were not sufficient. By the treatment of two-step cultured cells with calcium ionophore agent (A23187), the expression of co-stimulatory molecules such as CD86 and CD80 (especially CD86) was up-regulated. Besides, the expression of mature DC marker CD83 was remarkably induced by treatment with A23187 for a short duration (24 h). Consistent with the up-regulation of surface molecules CD86, CD80 and CD83, the two-step cultured cells treated with A23187 also showed a stronger allo-stimulatory capacity compared with the cells without A23187 treatment. In conclusion, the present study demonstrated that the two-step culture method effectively improved the yield of CD1a+ DC generated from CD34+ cells, and the phenotypes and functions of these CD1a+ DC could be enhanced efficiently by treatment with a calcium ionophore agent. 相似文献
112.
Active matrix metalloproteinases in the tear fluid of individuals with vernal keratoconjunctivitis 总被引:3,自引:0,他引:3
Kumagai N Yamamoto K Fukuda K Nakamura Y Fujitsu Y Nuno Y Nishida T 《The Journal of allergy and clinical immunology》2002,110(3):489-491
Corneal epithelial lesions distinguish vernal keratoconjunctivitis (VKC) from other ocular allergic diseases. Such lesions result from degradation of the corneal epithelial basement membrane, which comprises mostly type IV collagen and laminin. Matrix metalloproteinase 2 (MMP-2) and MMP-9 catalyze the degradation of these 2 extracellular matrix proteins. The possible role of MMP-2 and MMP-9 in the pathogenesis of corneal lesions associated with VKC was investigated by assaying tear fluid for the presence of these enzymes. Tear fluid was collected from 6 eyes of 6 patients with active VKC, 14 eyes of 14 patients with active allergic conjunctivitis, and 6 eyes of 6 nonallergic healthy volunteers. Gelatin zymography revealed that the tear fluid of healthy volunteers contained inactive proforms of both MMP-2 and MMP-9 but not the active forms of these enzymes. Active forms of MMP-2 or MMP-9 were detected in a minority of patients with allergic conjunctivitis. However, with the exception of one individual for whom active MMP-9 was not detected, tear fluid from all patients with VKC contained both proforms and active forms of MMP-2 and MMP-9. These results implicate MMP-2 and MMP-9 in the pathogenesis of corneal epithelial disorders associated with VKC. 相似文献
113.
Cellular localization of Babesia bovis merozoite rhoptry-associated protein 1 and its erythrocyte-binding activity 下载免费PDF全文
Yokoyama N Suthisak B Hirata H Matsuo T Inoue N Sugimoto C Igarashi I 《Infection and immunity》2002,70(10):5822-5826
The cellular localization of Babesia bovis rhoptry-associated protein 1 (RAP-1) and its erythrocyte-binding affinity were examined with anti-RAP-1 antibodies. In an indirect immunofluorescent antibody test, RAP-1 was detectable in all developmental stages of merozoites and in extracellular merozoites. In the early stage of merozoite development, RAP-1 appears as a dense accumulation, which later thins out and blankets the host cell cytoplasm, but retains a denser mass around newly formed parasite nuclei. The preferential accumulations of RAP-1 on the inner surface of a host cell membrane and bordering the parasite's outer surface were demonstrable by immunoelectron microscopy. An erythrocyte-binding assay with the lysate of merozoites demonstrated RAP-1 binding to both bovine and equine erythrocytes. Anti-RAP-1 monoclonal antibody 1C1 prevented the interaction of RAP-1 with bovine erythrocytes and significantly inhibited parasite proliferation in vitro. With the recombinant RAP-1, the addition of increasing concentrations of Ca(2+) accentuated its binding affinity with bovine erythrocytes. The present findings lend support to an earlier proposition of an erythrocytic binding role for RAP-1 expressed in B. bovis merozoites and, possibly, its involvement in the escape of newly formed merozoites from host cells. 相似文献
114.
Tadao Fukushima Yoji Nagashima Yukio Nakatani Nobuko Nakarnura Kiyoshi Fukasawa Yoshiaki Satomi Ken Yu Yohei Miyagi Ichiro Aoki Kazuaki Misugi 《Pathology international》1994,44(5):401-406
Chromophobe renal cell carcinoma (RCC) is a recently established subtype of RCC, which has rarely been reported in Japan. In this communication, the authors report two Japanese cases of chromophobe RCC together with the immunohistochemical findings. The tumors were composed of sheets and cribriform glands formed by tumor cells with cloudy and reticular cytoplasm. Ultrastructurally, the cytoplasm was filled with numerous microvesicles. The tumor cells were positive for cytokeratin, epithelial membrane antigen, and Tamm-Horsfall protein. Occasionally, LeuM1-positive cells were also noted. Vimentin was negative, unlike the usual RCC. Reactivity for peanut agglutinin was more frequent than that to Lotus tetragonolobus agglutinin. The results of this study suggest that the tumor cellq possessed phenotypes similar to the distal nephron rather than to the proximal tubular cells. 相似文献
115.
Diagnosis of Kala-Azar by Nested PCR Based on Amplification of the Leishmania Mini-Exon Gene 总被引:4,自引:0,他引:4 下载免费PDF全文
Ken Katakura Shin-Ichiro Kawazu Toshimitsu Naya Koichi Nagakura Mamoru Ito Masamichi Aikawa Jing-Qi Qu Li-Ren Guan Xin-Pin Zuo Jun-Jie Chai K.-P. Chang Yoshitsugu Matsumoto 《Journal of clinical microbiology》1998,36(8):2173-2177
To diagnose visceral leishmaniasis (kala-azar), we have developed a nested PCR method based on amplification of the mini-exon gene, which is unique and tandomly repeated in the Leishmania genome. Nested PCR was sufficiently sensitive for the detection of DNA in an amount equivalent to a single Leishmania parasite or less. We examined the usefulness of this PCR method using bone marrow aspirates and buffy coat cells collected from kala-azar patients who had or had not received chemotherapy in northwest China. We obtained PCR positivity for all of the parasitologically positive bone marrow samples from the patients. Some ambiguities with the primary PCR results were eliminated by the subsequent nested PCR. The buffy coat samples from 7 of 12 patients with splenomegaly were positive by the nested PCR, although only 2 of them were positive for parasites by culture. However, buffy coat samples from nine children, whose splenomegaly has been reduced and clinically cured by antimony treatment, were all negative. Thus, this nested PCR method represents a new tool for the diagnosis of kala-azar with patient blood samples instead of bone marrow or spleen aspirates obtained by more invasive procedures. 相似文献
116.
IMMUNOHISTOCHEMICAL DISTRIBUTION OF CANNABINOID CB 1 RECEPTOR IN THE RAT CENTRAL NERVOUS SYSTEM@邹冈 相似文献
117.
W. Ken Busfield Ian M. G. Cowie M. A. Sattar Mondal 《Macromolecular chemistry and physics.》1979,180(7):1775-1786
Two series of block copolymers have been synthesized comprising of soft polytrifluoroacetaldehyde (polyacetal) segments and of hard 4,4′-methylenedi(phenyl isocyanate)/cis-cyclohexane-1,4-diol polyurethane segments. The series-A copolymers in which the soft segments were directly bound to the hard segments had significantly lower thermal stability than the series-B copolymers in which the soft segments were linked to the hard segments by sebacic ester units. In both series the thermal stability decreased with increasing soft segment content. The series-A copolymers exhibited two thermal transitions both characteristic of Tg's and separated by about 60 K. In contrast the series-B copolymers exhibited two characteristic Tg's separated by 200–250 K, depending on composition, together with an additional endothermic transition at about ambient temperature. All transitions for both series decreased with increasing soft segment content. The observations have been compared with those of other polyether and polyester based polyurethanes. 相似文献
118.
Ken SAITO Hideo SHIMIZU Takeshi YOKOYAMA Katsuya KAWATA Takanori MATSUMURA Yasuhiko MORIOKA 《Pathology international》1983,33(2):249-256
Four cases of Ischemic enterocolitis without arterio–occlusive lesion were described. Three cases were associated with sigmoid colon carcinomas. Ischemic lesions developed anal to the carcinomas in two cases, and oral to sigmoidostomy to relieve intestinal obstruction by carcinoma in one case. One other case was associated with inguinal hernia. Grossly, ischemic lesions involved relatively short intestinal segments, and the ischemic colonic lesions were not related to teniae coli. Extensive veno–occlusive lesions were discovered in a case of ischemic stricture of the ileum, which had been incarcerated in the right inguinal hernia. Reversible mechanical occlusion of the intestinal vessels caused by transient or recurrent intestinal strangulation is the most probable cause of these ischemic lesions., ACTA PATHOL. JPN. 33: 249–256, 1983. 相似文献
119.
Satoh Y Ishikawa Y Miyoshi T Mukai H Okumura S Nakagawa K 《Virchows Archiv : an international journal of pathology》2003,442(2):173-178
Pulmonary metastasis from low-grade endometrial stromal sarcomas (ESSs) occasionally are found after long, disease-free periods, mostly as incidental histological or radiological discoveries. We describe a case of low-grade ESS presenting as nodular pulmonary metastases finally diagnosed by estrogen-receptor staining, cytogenetic and fluorescence in situ hybridization (FISH) analyses, and perusal of the histology of hysterectomy material. An abnormal nodule in the lung field was discovered by means of chest X-ray of a 47-year-old woman. She had been disease free for 13 years after hysterectomy for an alleged leiomyoma. A computed tomographic scan revealed nodules, with fluctuation in size over the 2-year period, in both lungs. Finally the lesion in the left lung was resected, and pulmonary endometriosis was suspected because of the lack of stromal cell nuclear atypia and positive immunohistochemical reactions for estrogen and progesterone receptors. However, a characteristic karyotype was identified cytogenetically: 46, XX, t(7;17)(p15;q11), the translocation of which, specific to ESS, was confirmed by FISH analysis. A final diagnosis of pulmonary metastases from an ESS could be made by reviewing the histology of the previous uterine tumor. In this case, metastatic lesions from an ESS showed a decrease as well as an increase in size, despite the malignant potential. Immunostaining for estrogen and progesterone receptors and cytogenetic and FISH analyses, together with clinical information on the past gynecological history, are valuable diagnostic keys. 相似文献
120.
Mireille Lahoud David Vremec Richard L. Boyd Ken Shortman 《Clinical & developmental immunology》1993,3(2):103-112
Thymic nurse cells (TNC), multicellular complexes consisting of lymphoid cells
enclosed within cortical epithelial cells, were isolated from mouse thymus by a modified
procedure allowing immunofluorescent labeling and flow cytometric analysis of their
lymphoid contents (TNC-L). Collagenase was the only protease used for tissue
digestion, to ensure that surface antigen markers remained intact. Zonal unit-gravity
elutriation was used to enrich the TNC on the basis of their high sedimentation rate,
followed by immunomagnetic bead depletion to remove residual mononuclear cell
contaminants and a density separation to remove debris. The TNC-L were then released
from inside TNC by a short period of culture. The measured contamination of TNC-L
with exogenous thymocytes was around 0.5%. Three-color immunofluorescent labeling
revealed that TNC-L included, as well as a maiority of immature CD4+8+3low thymocytes,
about 12% of apparently mature CD4+8-3high and CD4-8+3high thymocytes. TNC are
located in the cortex, where mature cells are rare; the occurrence of mature phenotype
cells within these structures suggests that they represent a microenvironment for the
selection and generation of mature T cells. 相似文献