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11.
Takuya Tsunoda Hiroshi Tanimura Hiroki Yamaue Makoto Iwahashi Masaji Tani Mikoko Tamai Kazuo Arii Kohei Noguchi 《Biotherapy》1992,4(1):9-15
In adoptive immunotherapy, the number of effector cells is one of the major factors relating to the therapeutic efficacy. We demonstrated that tumor-infiltrating lymphocytes (TILs) were stimulated to proliferate by incubation with interleukin 2 (IL-2) plus interleukin 4 (IL-4). TILs cultured with IL-2 plus IL-4 increased 3.1-fold more than TILs cultured with IL-2 alone. However, IL-4 did not alter the cytotoxic activity of TILs against autologous tumor cells and established tumor cell lines. It is suggested that IL-2 receptor is related to the mechanism of the proliferation of activated TILs cultured by combination with IL-2 and IL-4. Thus, the combination of IL-2 and IL-4 may increase the efficacy of adoptive immunotherapy using activated TILs. 相似文献
12.
Incorporation of fatty acids by Streptococcus mutans 总被引:1,自引:0,他引:1
Masaru Sato Hironori Tsuchiya Hideki Tani Kohji Yamamoto Ryozo Yamaguchi Hiroshi Nitta Nobutake Kanematsu Isamu Namikawa Nobuhiko Takagi 《FEMS microbiology letters》1991,81(1):117-121
In a series of investigations into the cariogenicity of Streptococcus mutans, we studied the incorporation of exogenous fatty acids with reference to glucosyltransferase secretion and membrane fatty acid changes. When cells were grown with different fatty acids, both saturated and unsaturated fatty acids were readily incorporated into the membrane lipids and were biotransformed and elongated preferentially to the longer 16- and 18-carbon-chain fatty acids. This incorporation and chain-elongation led to significant changes in fatty acids composition. By adding fatty acids to the medium, it was possible to appropriately modify the degree of unsaturation and the relative ratio between specific fatty acids in the membrane lipids of S. mutans. 相似文献
13.
Characteristic distribution of cathepsin E which immunologically cross-reacts with the 86-kDa acid proteinase from rat gastric mucosa 总被引:2,自引:0,他引:2
The antiserum raised against the high-molecular-weight acid proteinase from rat gastric mucosa, termed 86-kDa acid proteinase, has been shown to recognize rat cathepsin E, but not cathepsin D (Muto, N. et al. (1987) J. Biochem. 101, 1069-1075). Using this specific antiserum, characteristic distribution of cathepsin E in rats was demonstrated. The enzyme was detected in a limited number of tissues, such as stomach, thymus, spleen, bladder, and erythrocyte membranes. Among them, the highest activity was observed in the stomach. In contrast, cathepsin D immunoreactive with the antiserum specific to rat gastric cathepsin D was demonstrated in all the tissues examined. Cathepsin E-type enzymes partially purified from these five tissues were precipitated in the same manner by the specific antiserum, and they had the same molecular weight, electrophoretic mobility, and resistance against denaturation by 4 M urea. These results indicate that they could be exactly classified as cathepsin E. This type of enzyme was also detectable in mice and guinea pigs, but they showed relatively weak immunoreactivities with the antiserum. Thus, it is concluded that the distribution of cathepsin E is intrinsically different from ordinary cathepsin D, suggesting that it has a different physiological role from cathepsin D. 相似文献
14.
G Steiner E Tschachler M Tani T R Malek E M Shevach W Holter W Knapp K Wolff G Stingl 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(1):155-159
Rat monoclonal antibodies 3C7 and 7D4 detect two distinct functional regions of the murine interleukin 2 (IL 2) receptor. When studying the emergence kinetics of IL 2 receptors in mixed epidermal cell (EC)-lymphocyte cultures by using 3C7 and 7D4 in an indirect immunofluorescence assay, we regularly encountered a distinctive membrane fluorescence not only on lymphocytes, but also on a subpopulation of cells exhibiting a dendritic morphology. Reasoning that these 3C7/7D4-reactive dendritic cells might represent a subpopulation of epidermal dendritic cells, we studied mouse EC for the presence of 3C7/7D4- reactive cells. Although 3C7/7D4 reactivity was never detected on freshly isolated EC or on epidermal sheets, a small number of 3C7/7D4+ cells was encountered after 24 to 48 hr of culture. These cells exhibited a dendritic shape, expressed Ia antigens, lacked Thy-1 antigens, and displayed the ultrastructural features of Langerhans cells (LC) with the notable exception of Birbeck granules. Although after 24 hr, only 20% of Ia+ EC were 3C7/7D4+, the vast majority of LC displayed 3C7/7D4 binding sites after 4 to 5 days of culture. Preincubation of cultured LC-enriched EC with recombinant human IL 2 prevented subsequent 3C7-but not 7D4-binding to these cells. Western blot analysis of 7D4-reactive material of detergent extracts from LC-enriched EC revealed three bands in the same m.w. range as reported for CTLL cells. These results demonstrate that cultured LC express IL 2 receptors and may bear important implications for a better understanding of growth regulation, differentiation, and immunologic functions of LC. 相似文献
15.
A large chondroitin sulfate proteoglycan (PG-M) synthesized before chondrogenesis in the limb bud of chick embryo 总被引:13,自引:0,他引:13
K Kimata Y Oike K Tani T Shinomura M Yamagata M Uritani S Suzuki 《The Journal of biological chemistry》1986,261(29):13517-13525
Extraction of stage 22-23 chick embryo limb buds that had been metabolically labeled with [35S]sulfate yielded heparan sulfate proteoglycan, small chondroitin sulfate proteoglycan, and large chondroitin sulfate proteoglycan (designated PG-M). PG-M constituted over 60% of the total macromolecular [35S]sulfates. It was larger in hydrodynamic size, richer in protein, and contained fewer chondroitin sulfate chains as compared to the predominant proteoglycan (PG-H, Mr congruent to 1.5 X 10(6)) of chick embryo cartilage. The chondroitin sulfate chains were notable for their large size (Mr greater than or equal to 60,000) and high content of nonsulfated chondroitin units (about 20% of the total hexosamine). Hexosamine-containing chains corresponding in size to N-linked and O-linked oligosaccharides were also present. The core protein was rich in serine, glutamic acid (glutamine), and glycine which together comprised about 38% of the total amino acids. Following chondroitinase AC II (or ABC) digestion, core molecules were obtained which migrated on sodium dodecyl sulfate gel electrophoresis as a doublet of bands with approximately Mr = 550,000 (major) and 500,000, respectively. The Mr = 550,000 core glycoprotein was structurally different from the core glycoprotein (Mr congruent to 400,000) of PG-H, as ascertained by tryptic peptide mapping and immunochemical criteria. Immunofluorescent localization of PG-M showed that the intensity of PG-M staining progressively became higher in the core mesenchyme region than in the peripheral loose mesenchyme, closely following the condensation of mesenchymal cells. Since the cell condensation process has been shown to begin with the increase of fibronectin and type I collagen concentration, the similar change in PG-M distribution suggests that PG-M plays an important role in the cell condensation process by means of its interaction with fibronectin and type I collagen. 相似文献
16.
17.
A New Enzymatic Cycling Technique for Glutamate Determination in Brain Microdialysates 总被引:2,自引:1,他引:1
Akira Mitani Hirohiko Kubo Kouzo Iga Hitoshi Imon Fumito Kadoya Kiyoshi Kataoka 《Journal of neurochemistry》1990,54(2):709-711
A quantitative analysis of glutamate in brain dialysate was made by using an enzymatic cycling technique. This method made it possible to measure the concentration of glutamate in dialysate collected at 30-s intervals. Dialysates were collected from Mongolian gerbil hippocampus before, during, and after two 90-s ischemic insults at an interval of 5 min. An extracellular increase in levels of glutamate was already observed in samples collected during a 30-60 s period after the onset of each ischemia, and the levels of glutamate were maximal at the end of each period of ischemia (approximately a fourfold increase). The increased levels of glutamate rapidly returned almost to preischemic levels by 30 s of recirculation. This method will provide more precise information about temporal changes in the extracellular glutamate concentration in the brain during ischemia. 相似文献
18.
The cytologic findings in fine needle aspirates of a previously treated prostatic cancer metastatic to both breasts in a 65-year-old man are described. The prostatic origin of the poorly differentiated adenocarcinoma cells was demonstrated by identification of cytoplasmic prostate-specific antigen. The clinical importance of a conclusive diagnosis differentiating a primary from a metastatic lesion is discussed; this case illustrates the value of immunocytochemical analysis as an aid to cytomorphologic diagnosis in making such determinations. 相似文献
19.
K Tani K Shiozuka H Tokuda S Mizushima 《The Journal of biological chemistry》1989,264(31):18582-18588
The proton motive force (delta mu H+) plays an important role, although it is not absolutely essential, in the in vitro translocation of secretory proteins, such as OmpA, across the cytoplasmic membrane of Escherichia coli (Yamada, H., Tokuda, H., and Mizushima, S. (1989) J. Biol. Chem. 264, 1723-1728). The transient accumulation in membrane vesicles of a possible translocation intermediate of OmpA was observed in the absence of delta mu H+. The intermediate was detected on a polyacrylamide gel as a proteinase K-resistant band corresponding to a molecular weight of 26,000. The intermediate did not possess the signal peptide. The appearance of this band was inhibited in the absence of ATP or the presence of adenosine 5'-(beta,gamma-imino)triphosphate (AMP-PNP) and enhanced upon the addition of SecA. Upon the addition of NADH that energizes the membrane, the intermediate was converted to the translocated form of OmpA, even in the presence of AMP-PNP. These results suggest different requirements of ATP and delta mu H+ for the early and late stages of the translocation reaction. The SecA requirement for the early stage of the translocation has also been suggested. In addition to this band, two other bands were observed at higher positions on the gel, when the translocation reaction was performed in the absence of delta mu H+. Although these two bands also represented the mature form of OmpA, which was partly protected from the proteinase K treatment by the membrane vesicles, the accumulation was not transient. These bands did not appear when the translocation reaction was performed in the presence of dithiothreitol. Together with other evidence, the above observations suggest that OmpA, which has an intramolecular disulfide bridge, cannot undergo the translocation unless delta mu H+ is imposed. 相似文献
20.
Maruyama Akiko; Yoshiyama Makoto; Adachi Yasuhiro; Tani Akinobu; Hasegawa Ryo; Esashi Yohji 《Plant & cell physiology》1996,37(8):1054-1058
The effects of allyl, sulfur and cyanogenic compounds on thegermination of upper cocklebur (Xanthium pennsylvanicum Wallr.)seeds were examined. Mercaptoethanol and methylmercaptan aswell as KCN, substrates for rßcyanoalanine synthase(CAS), and H2S and thiocyanate, the products of the CAS catalyzingreaction, were effective in promoting germination, suggestingthe involvement of CAS in germination. Most of allyl compounds, especially allylthiourea, as well asethylene which activated CAS [Hasegawa et al. (1994) Physiol.Plant. 91: 141], promoted the germination in an abnormal typewhich occurred by the predominant growth of cotyledons as didC2H4 [Katoh and Esashi (1975) Plant Cell Physiol. 16: 687].However, they failed to activate CAS unlike ethylene, and toliberate free ethylene during an incubation period. It was thuspossible that an C2H4-like double bond within allyl compoundscan act to promote seed germination. (Received June 10, 1996; Accepted August 21, 1996) 相似文献