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1.
Unfractionated human peripheral blood mononuclear cells produce a small amount of interleukin 2 (IL 2) by stimulation with a monoclonal anti-T3 antibody (OKT3) in vitro. The IL 2 production could be greatly augmented by the addition of a phorbol ester, 12-O-tetradecanoyl-phorbol-13-acetate (TPA). In the presence of TPA, the T cell enriched fraction deprived of macrophages did not produce IL 2, but the T cells pulse-incubated with OKT3 and reconstituted with macrophages efficiently produced IL 2 in subsequent culture in the presence of TPA as did T cells reconstituted with OKT3-pulse-incubated macrophages. The stimulating effect of OKT3 in the presence of macrophages was inhibited dose-dependently by the addition of immunoglobulins, particularly by mouse IgG2a which is the same isotype as that of the OKT3 antibody, showing that it inhibits by blocking the binding of OKT3 to Fc receptors on macrophages. The same extent of IL 2 production was induced in T cells when paraformaldehyde-fixed macrophages were substituted for intact macrophages. Remarkable IL 2 production was also induced by OKT3 when latex beads coated with rabbit anti-mouse IgG2a antibody and TPA were added to the culture. It was confirmed that the production induced by these stimulations was due to an increase of IL 2 mRNA. These results show that effective signals for IL 2 production are generated by efficient crosslinking of T3 molecules which results from multi-interaction of T3 molecules on the T cell membrane and anti-T3 antibody molecules on macrophage membrane or on the surface of the latex particle. 相似文献
2.
Kunitoshi Yamanaka Teru Ogura Kazuyoshi Murata Toshinobu Suzaki Hironori Niki Sota Hiraga 《FEMS microbiology letters》1994,116(1):61-66
Abstract The smbA gene of Escherichia coli is essential for cell proliferation. The smbA2 mutant shows cold-sensitive colony formation at 22°C. A novel morphological phenotype, formation of a translucent segment at midcell or at a cell pole, was observed by phase-contrastt microscopy at a high frequency in the smbA2 mutant cells incubated in L medium lacking NaCl at 22°C, but not observed in L medium containing 1% NaCl or 20% sucrose at the same temperature. No translucent segment was observed in the wild-type cells in any of the media used. Electron microscopic observation revealed that the translucent segments resulted from the enlargement of a periplasmic space by separation of the inner membrane from the peptidoglycan layer and the outer membrane. 相似文献
3.
Primary structures of two types of alpha-subunit of rat brain Na+,K+,-ATPase deduced from cDNA sequences 总被引:2,自引:0,他引:2
Y Hara O Urayama K Kawakami H Nojima H Nagamune T Kojima T Ohta K Nagano M Nakao 《Journal of biochemistry》1987,102(1):43-58
A rat brain cDNA library was screened by using as a probe a fragment of cDNA encoding the alpha-subunit of human Na+,K+-ATPase. Two different cDNA clones were obtained and analyzed. One of them was concluded to be a cDNA encoding the alpha-subunit of the weakly ouabain-sensitive rat kidney-type Na+,K+-ATPase. The deduced amino acid sequence consists of 1,018 amino acids. The alpha-subunit of the rat kidney-type Na+,K+-ATPase shows 97% homology in amino acid sequence with the alpha-subunit of human, sheep, or pig enzyme and 87% with that of Torpedo. Based on a comparison of the amino acid sequence at the extracellular domain of the alpha-subunit between weakly ouabain-sensitive rat kidney-type enzyme and the ouabain-sensitive human, sheep, pig, or Torpedo enzyme, it was proposed that only two significant amino acid replacements are unique to the rat kidney-type alpha-subunit. Another cDNA clone obtained showed 72% homology in nucleotide sequence with the former cDNA coding the alpha-subunit of the rat kidney-type Na+,K+-ATPase and the deduced amino acid sequence exhibited 85% homology with that of the alpha-subunit of rat kidney-type Na+,K+-ATPase. 相似文献
4.
S Abe Y Tsuneta S Makimura K Itabashi T Nagai Y Kawakami 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1987,9(5):425-428
The relationship between the nuclear DNA histogram pattern of tumor cells obtained by bronchoscopic brushing and the response to combination chemotherapy (Cytoxan + Adriamycin + Vincristine) was studied in 28 patients with small-cell carcinoma of the lung. Microspectrophotometric analysis of the tumor cells showed a near-diploid nuclear DNA pattern in 18 patients and a hyperdiploid pattern in 10 patients. Eight of the ten patients with the hyperdiploid pattern showed a good response (complete or partial response) to the chemotherapy. However, of the 18 patients with the near-diploid DNA pattern, only 2 displayed a good response; the remaining 16 patients exhibited no response. The hyperdiploid DNA pattern of tumor cells was thus associated with a better response to chemotherapy than was the near-diploid pattern. These results indicate that the nuclear DNA histogram pattern may be an indicator for predicting the degree of response to chemotherapy in small-cell carcinoma of the lung. 相似文献
5.
Summary Spacing and kinship of the Formosan squirrel, Callosciurus erythraeus thaiwanensis, were studied in two different habitats. One, native habitat in the woods of Kenting, southern Formosa, was rich in available food throughout the year and had several species of predators. The other, a site in Kamakura, central Japan where squirrels had been introduced, had relatively scanty food and few potential predators. 1. Home ranges among males and between sexes overlapped extensively in both habitats. 2. Females occupied exclusive home ranges in Kamakura but had small overlapping home ranges in Ken-ting. 3. Most males disappeared from their natal areas at 1 year old in both habitats (86% in Kamakura and 93% in Ken-ting), but less females disappeared (36% in Kamakura and 35% in Ken-ting). 4. In Kamakura, daughters settled adjacent to the mother or inherited the home range of the mother, but never shared the mother's home range. In Ken-ting, 35% of daughters shared the home range with their mothers. 5. Tolerance among female kin in Ken-ting was probably facilitated by the richness of available food throughout the year, and functioned to reduce predation risk via alarm calling and mobbing. 相似文献
6.
Microfibrils (MFs) on the inner surface of the walls of Avenacoleoptile and mesocotyl cells and of Pisum epicotyl cells wereexamined by a replica method. In the elongating epidermis ofthese three organs, cells having MFs that were transverse, obliqueor longitudinal to the elongation axis were intermingled. Inthe elongating parenchymal tissues, all cells deposited MFstransversely. In non-elongating cells of Avena coleoptiles andPisum epicotyls, the orientation of MFs on the inner wall surfaceof both epidermal and parenchymal cells was more longitudinalthan in elongating cells. These observations on the orientationsof MFs are compatible with those our previously reported observationson the orientations of microtubules (MT) (Iwata and Hogetsu1988). Disruption of MTs of Avena coleoptiles by treatment withamiprophosmethyl caused changes in the orientation of depositionof MFs. These results support the idea that MFs are usuallyco-aligned with MTs in organ cells and that the orientationof MFs is controlled by MTs. The averaged direction of MFs, visualized under polarized light,showed a clear difference between the epidermal and inner-tissuecell walls in the elongating regions of the three organs. Inalmost all elongating and non-elongating epidermal cells, theaveraged direction of MFs was longitudinal, while it was transversein all inner-tissue cells. (Received December 16, 1988; Accepted April 28, 1989) 相似文献
7.
Identification of the cell surface molecule involved in sexual cell fusion of Dictyostelium discoideum 总被引:6,自引:0,他引:6
Kazuyoshi Suzuki Kaichiro Yanagisawa 《Differentiation; research in biological diversity》1989,40(3):159-165
Dictyostelium discoideum was used as a model system for elucidating the molecular mechanism of sexual cell fusion. In heterothallic strains NC4 and HM1 of D. discoideum, complements in mating type, amoeboid cells acquire fusion competence only under certain environmental conditions, such as the presence of excess water and a certain period of darkness, to fuse sexually. The surface of cells which acquired fusion competence was found to possess specific antigens. Monovalent antibodies prepared from rabbit antiserum against fusion-competent NC4 cells inhibit the sexual cell fusion of these cells completely. Two specific antigenic proteins, 39 and 138 k Da in relative molecular mass and specific for fusion-competent cells, were detected. Only one, the 138-k Da protein, was capable of neutralizing the fusion-inhibitory activity of the monovalent antibody. These results show that the 139-k Da protein is the one involved in the sexual cell fusion of NC4 and HM1 strains in D. discoideum. 相似文献
8.
Differences in lectin binding patterns of normal human endometrium between proliferative and secretory phases 总被引:3,自引:0,他引:3
Lectin binding patterns in normal human endometrium were examined by light and electron microscopy using seven different lectins (ConA, WGA, RCA, PNA, UEA-1, DBA, and SBA). For light microscopic observations, criteria based on the incidence and intensity of cells positive for the lectin staining were adopted to evaluate the different staining patterns of the proliferative and secretory endometria obtained by the avidin-biotin-peroxidase complex (ABC) technique. At the light microscopic level, ConA, WGA, and RCA stained endometrial glandular cells in both phases. The number of PNA-positive cells with the binding sites entirely limited to the apical surface tended to be reduced slightly in the secretory phase. UEA-1 weakly stained the apical surface of glandular cells in the proliferative phase but not in the secretory phase. Among the lectins used in this study, DBA and SBA displayed remarkable changes between the phases. That is, in the proliferative phase they produced only a faint or slight positive stain at the apical surface, but the incidence and intensity of DBA- and the SBA-positive glandular cells increased in the secretory phase. By electron microscopy, the reaction product of ConA was observed in the plasma membrane, endoplasmic reticulum, nuclear envelope, and the Golgi apparatus, and the binding sites of RCA and DBA were observed in the plasma and Golgi membranes. Between both phases, the reactivity of ConA and RCA showed almost no change. However, the secretory endometrial cells containing the DBA-positive Golgi apparatus were markedly increased in number compared with the proliferative ones bearing the lectin-positive organelles.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Masafumi Abe Naoya Nakamura Shirou Fukuhara Takamasa Hayashi Keiki Kawakami Kenkichi Kita Toshifumi Kinoshita Toyoro Ohsato Haruki Wakasa 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):107-113
A new human acute lymphoblastic leukemia (ALL) cell line, designated HBL-3, was established from the bone marrow of a patient
with non-T-ALL. The HBL-3 cell line expressed B4 (CD 19), BA-1 (CD 24) and HLA-DR antigens, but not surface immunoglobulin
(SIg) or cytoplasmic immunoglobulin (CIg). The cell line lacked the common acute lymphoblastic leukemia antigen (CALLA) and
antigenic markers characteristic of T-cell and myeloid cell lineages. The HBL-3 cells had structural rearrangements of both
the homologous chromosome 9s, including a translocation with chromosome 1 which has been reported in a patient with common
ALL. The cell line had rearranged immunoglobulin heavy chain genes but retained germ-line κ light chain genes and germ-line
T-cell receptorβ- and γ-chain genes. The HBL-3 cell line was strongly positive for terminal deoxynucleotidyl transferase (TdT). These findings
indicate that the HBL-3 cell line is derived from the earliest B-cell committed to B-cell lineage. 相似文献
10.
M. Jane Ehrke Richard L. X. Ho Kazuyoshi Hori 《Cancer immunology, immunotherapy : CII》1988,27(2):103-108
Summary Recombinant murine (rMu) tumor necrosis factor (TNF), in a standard comitogenic assay with phytohemagglutinin, induced murine thymocyte proliferation, while up to 10,000-fold higher concentrations of recombinant human TNF did not. The induction of thymocyte proliferation was dependent upon TNF concentration in a biphasic manner. Thus, 100 to 1000 units/ml TNF were near optimal while concentrations 1,000 units/ml caused apparent down regulation. The effect was abrogated by neutralizing antibody to rMu-TNF but not by neutralizing antibody to rMu-interleukin 1 or . The rMu-TNF did not induce proliferation of the mature murine T-helper cell line, D10.G4.1, in the presence of mitogen. Taken together the results indicate that TNF, in a strictly species-specific manner, can regulate thymocyte proliferation independently of interleukin 1.Supported in part by Asahi Chemical Industry Co., Inc. and by USPHS Grants CA-24538, CA-15142 and CA-09072 awarded by the National Cancer Institute, Department of Health and Human Services 相似文献