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11.
12.
Specific cytolysis of fresh tumor cells by an autologous killer T cell line derived from an adult T cell leukemia/lymphoma patient 总被引:8,自引:0,他引:8
M Kannagi K Sugamura K Kinoshita H Uchino Y Hinuma 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(2):1037-1041
Cytotoxic T cells (Tc) derived from one patient with adult T cell leukemia/lymphoma (ATL) killed fresh autologous lymphoma cells in vitro. The Tc were induced from peripheral blood leukocytes (PBL) of this patient during remission by multiple in vitro stimulations with an autologous ATLV-bearing cell line (ILT) that was previously established by cloning of PBL in the presence of interleukin 2 (IL 2). PBL from eight other ATL patients were stimulated in the same manner, and responder cells from a patient in remission also showed cytotoxicity specific for ATL virus (ATLV)-bearing cells. Fresh lymphoma cells were obtained in relapse and were used as target cells for the autologous Tc induced. They became susceptible to the Tc within 4 hr of in vitro incubation, and their susceptibility increased with incubation time for at least 12 hr. ATLV antigens on the cell surface of these lymphoma cells, however, were not detected by radioimmunoassay during these incubation periods, but were detectable after 16 hr of incubation. In addition, cytotoxicity against lymphoma cells was completely inhibited by autologous ILT cells used as "cold" target competitor cells. These findings indicate that the target antigen of the Tc was expressed on both autologous ILT cells and lymphoma cells, and it may be different from ATLV antigens detected by serologic methods. In addition, the data suggested allogeneic restriction of the Tc in that the preferentially killed allogeneic ATLV-bearing cells share several HLA antigens. 相似文献
13.
The sex-specific glycoprotein agglutination substance, responsiblefor sexual agglutination, solubilized from the surface of haploidcells of a or a mating type by the autoclave method had thefollowing effects on mating reaction in Saccharomyces cerevisiae.Sexual agglutination was inhibited by the agglutination substanceof the opposite mating type in living cells as well as in heat-killedcells. Formation of zygotes was completely inhibited, when botha and a cells were treated with the agglutination substanceof the opposite mating type. The a and a agglutination substanceswere inactivated by cells of the opposite mating type, withthe degree of inactivation being greater for the former. Theenzyme responsible for the inactivation of a agglutination substanceseems to be carboxypeptidase Y.
1 This paper is dedicated to the late Professor J. Ashida, KyotoUniversity.
2 Present address: Department of Plant Pathology, Universityof California, Davis, CA. 95616, U.S.A. (Received November 1, 1982; Accepted January 19, 1983) 相似文献
14.
Simple approximate expressions have been derived from the theory of Zimm and Bragg for use in the analysis of experimental data on the helix-coil transition in polypeptide. On the basis of the resulting expressions practical procedures are proposed to determine two basic parameters characterizing a thermally induced transition, i.e., helix initiation parameter σ and enthalpy change for helix formation, ΔH. They have been applied to the data for poly(β-benzyl L -aspartate) (PBLA) with the result: σ = 1.6 × 10?4 and ΔH = ?450 cal/mole for PBLA in m-cresol; σ = 0.6 × 10?4 and ΔH = 260 cal/mole for PBLA in chloroform containing 5.7 vol-% of dichloroacetic acid. This result gives evidence that σ may change not only from one polypeptide to another but also for a given polypeptide in different solvents. The change in limiting viscosity number [η] accompanying the transition was measured in the same solvents. The curve of [η] versus helical content had a relatively monotonic shape for the chloroformdichloroacetic acid solutions as compared with that for the m-cresol solutions, indicating that [η] depended largely on σ. Provided that [η] is a direct measure of the mean-square radius of gyration, 〈S2〉, the results are consistent with the theoretical predictions of Nagai and of Miller and Flory for 〈S2〉. 相似文献
15.
16.
Two different protease genes were cloned fromRhodocyclus gelatinosa APR 3-2 inEscherichia coli HB 101/ with pBR329 or its derivatives. The recombinant plasmids designated as pRP100 and pRP300 contained 11.2 and 10.6 kb DNA fragments, respectively. The differences of both plasmids in restriction enzyme maps indicate that these plasmids contained different protease genes. DNA fragments coding for protease, 6.4 kb and 4.5 kb from pRP100 and pRP300, were subcloned into pRP329 and designated as pRP101 and pRP301, respectively. The two cloned proteases were excreted in culture medium ofE. coli, and ß-lactamase ofE. coli, which was originally localized in periplasmic space, was also excreted in the medium. 相似文献
17.
Recombinational hotspot specific to female meiosis in the mouse major histocompatibility complex 总被引:13,自引:0,他引:13
Toshihiko Shiroishi Naoto Hanzawa Tomoko Sagai Masahiro Ishiura Takashi Gojobori Michael Steinmetz Kazuo Moriwaki 《Immunogenetics》1990,31(2):79-88
Thewm7 haplotype of the major histocompatibility complex (MHC), derived from the Japanese wild mouseMus musculus molossinus, enhances recombination specific to female meiosis in theK/A
interval of the MHC. We have mapped crossover points of fifteen independent recombinants from genetic crosses of thewm7 and laboratory haplotypes. Most of them were confined to a short segment of approximately 1 kilobase (kb) of DNA between theA
3 andA
2 genes, indicating the presence of a female-specific recombinational hotspot. Its location overlaps with a sex-independent hotspot previously identified in theMus musculus castaneus CAS3 haplotype. We have cloned and sequenced DNA fragments surrounding the hotspot from thewm7 haplotype and the corresponding regions from the hotspot-negative B10.A and C57BL/10 strains. There is no significant difference between the sequences of these three strains, or between these and the published sequences of the CAS3 and C57BL/6 strains. However, a comparison of this A3/A2 hotspot with a previously characterized hotspot in theE gene revealed that they have a very similar molecular organization. Each hotspot consists of two elements, the consensus sequence of the mouse middle repetitive MT family and the tetrameric repeated sequences, which are separated by 1 kb of DNA.The nucleotide sequence data reported in this paper have been submitted to the DNA Data Bank of Japan nucleotide sequence database and have been assigned the accession numbers d90007-9.
Offprint requests to: T. Shiroishi. 相似文献
18.
5-Deoxy-5-nucleosideacetic acids II–V are isostructural analogues of nucleotides with a carboxylate group in the place of the 5-phosphate group. We have studied their oligomerization in aqueous solution using a water-soluble carbodiimide as the condensing agent in the presence or absence of an appropriate polynucleotide template. Condensation of adenylic acid analogues IIa, IIIa, and Va in the presence of polyuridylic acid were found to be the most efficient reactions. Cyclization of the activated monomers to lactones and the insolubility of the oligomers in aqueous solution were found to be obstacles to the efficient formation of long oligomers. 相似文献
19.
To elucidate the role of interleukin 2 (IL-2) activation in CD3- lymphocytes, we examined the ability of monoclonal antibody (MAb) TU27, developed against the IL-2 receptor (IL-2R) p75 protein (IL-2R beta), to block lymphocyte activation with exogenous IL-2, as well as its innate ability to activate lymphocytes as a result of its surface ligand interaction. The binding of the TU27 MAb and the results of 125I-IL-2 cross-linking experiments suggest that the IL-2R beta chain is expressed primarily on CD3-, CD56+ lymphocytes; although the protein was also detected in a small portion of CD3+ cells, its expression appeared to be donor dependent. In the present study, we found that TU27 totally blocked natural killer (NK) cell activation in a 4-h assay but had no effect on basal levels of NK activity. When treatment was extended to 24 to 72 h, the MAb was able to block the induction of both NK and lymphokine-activated killer (LAK) activity. Of interest was the observation that MAb treatment alone augmented NK activity and subsequent interferon gamma (IFN gamma) production in CD3- lymphocytes but did not activate LAK activity or induce cell growth. Collectively, these results indicate that TU27 not only reacts with p70-75 IL-2R beta but can abrogate IL-2 binding and subsequent activation events. In addition, some CD3- lymphocyte functions (e.g., NK activity and IFN gamma secretion) are directly induced by the binding of MAb to p70-75 through signals that only partially mimic IL-2. 相似文献
20.
Satoshi Iuchi Kazuko Yamaguchi-Shinozaki Takeshi Urao Kazuo Shinozaki 《Journal of plant research》1996,109(4):415-424
Ten cDNAs for drought-inducible genes were isolated using differential screening of a cDNA library prepared from 10-hr dehydrated
cowpea plants,Vigna unguiculata (S. Iuchi, K. Yamaguchi-Shinozaki, T. Urao, T. Terao, K. Shinozaki; Plant Cell Physiology, 1996 in press). Two of the cDNA
clones, designated CPRD12 and CPRD46, were sequenced and characterized. The CPRD12 and CPRD46 cDNAs encode putative proteins
related to nonmetallo-short-chain alcohol dehydrogenase (CPRD12) and chloroplastic lipoxygenase (CPRD46). Northern blot analysis
revealed that these genes are induced by high-salinity stress and exogenous abscisic acid, but not by cold stress. The CPRD46
gene is also responsive to heat stress and methyl jasmonate and salicylic acid. Genomic Southern blot analysis suggested that
CPRD12 constitutes a small gene family, but that CPRD46 is a single copy gene. We discuss the possible functions of these
two CPRD gene products under drought stress. 相似文献