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91.
Graham Pawelec Gerhard Ehninger Helmuth Schmidt Claudia Müller Hans-Jörg Bühring Markus Reutter Friedrich W. Busch 《Cancer immunology, immunotherapy : CII》1990,32(3):167-172
Summary Chronic myelogenous leukemia (CML) patients in chronic phase display compromised lymphokine-activated killer (LAK) cell induction, which is partly restored after therapy with interferon . However, the relative resistance of the leukemic cells from these patients to autologous or allogeneic LAK lysis is not affected by this treatment. In an attempt to render CML cells more susceptible to lysis or cytostasis, they were precultured in serum-free medium with or without recombinant growth factors. In eight patients studied, interleukin-3 (IL-3) significantly enhanced the spontaneous short-term (6-day) proliferation of CML cells, with retention of ability to form colonies in methylcellulose. Culture in either medium alone or IL-3 led to a significant enrichment of CD14+ and CD33+ cells but to a reduction in CD34+ cells. In contrast, culture of the same cells in IL-2 (to generate autologous LAK activity) resulted in a loss of CD14+ and CD33+ as well as CD34+ cells but in a significant increase in CD3+ and CD56+ cells. Despite similarities in their phenotypes, IL-3 cultured cells but not those cultured in medium alone acquired susceptibility to lysis by the IL-2-cultured autologous LAK cells. These results may have significance for the design of novel combination immunotherapy in CML.This work was supported in part by the Deutsche Forschungsgemeinschaft (SFB 120) 相似文献
92.
Abstract 3-Chlorobiphenyl-degrading bacteria were obtained from the mating between Pseudomonas putida strain BN10 and Pseudomonas sp. strain B13. Strains such as BN210 resulted from the transfer of the genes coding the enzyme sequence for the degradation of chlorocatechols from B13 into BN10, whereas B13 derivatives such as B131 have acquired the biphenyl degradation sequence from BN10. During growth of the hybrid strains on 3-chlorobiphenyl 90% chloride was released. Activities of phenylcatechol 2,3-dioxygenase, benzoate dioxygenase, catechol 1,2-dioxygenase, chloromuconate cyloisomerase and 4-carboxymethyl-enebut-2-en-4-olide hydrolase were found in 3-chlorobiphenyl-grown cells. The hybrid strains were found to convert some congeners of the Aroclor 1221 mixture such as mono- and dichloro-substituted biphenyls. 相似文献
93.
Metabolism of phospholipids on erythrocyte membranes 总被引:2,自引:0,他引:2
94.
Twelve loci have been assigned to rat chromosome 5: aldolase B (ALDOB), atrial natriuretic factor (ANF = pronatriodilatin, PND), D4RP1, DSI1, galactosyltransferase (GGTB2), glucose transporter (GLUT1), interferon alpha 1 and related interferon alpha (INFA), interferon beta (INFB), lymphocyte-specific protein-tyrosine kinase (LCK), oncogene MOS, alpha 2U-globulin (major urinary protein, MUP), and orosomucoid (ORM, also called alpha 1-acid glycoprotein, AGP). Among these, the interferon alpha and beta genes map in the q22-23 region, which also contains a transformation suppressor gene (SAI1). The other loci reside outside this region. This study also indicated that the rat genome contains 2 LCK genes, unlike the human and murine genomes. These new assignments on rat chromosome 5 demonstrate that this chromosome is highly homologous to mouse chromosome 4 and carries synteny groups conserved on human chromosome 9 (interferon alpha and beta, galactosyltransferase, orosomucoid, and aldolase B genes) and on the short arm of human chromosome 1 (MYCL, glucose transporter, protein kinase LCK, and atrial natriuretic factor genes). 相似文献
95.
Dr. Christoph Viebahn E. Birgitte Lane Frans C. S. Ramaekers 《Cell and tissue research》1988,253(3):553-562
Summary The expression of vimentin and keratins is analysed in the early postimplantation embryo of the rabbit at 11 days post conceptionem (d.p.c.) using a panel of monoclonal antibodies specific for single intermediate filament polypeptides (keratins 7, 8, 18, 19 and vimentin) and a pan-epithelial monoclonal keratin antibody. Electrophoretic separation of cytoskeletal preparations obtained from embryonic tissues, in combination with immunoblotting of the resulting polypeptide bands, demonstrates the presence of the rabbit equivalents of human keratins 8, 18, and vimentin in 11-day-old rabbit embryonic tissues. Immunohistochemical staining shows that several embryonic epithelia such as notochord, surface ectoderm, primitive intestinal tube, and mesonephric duct, express keratins, while others (neural tube, dermomyotome) express vimentin, and a third group (coelomic epithelia) can express both. Similarly, of the mesenchymal tissues sclerotomal mesenchyme expresses vimentin, while somatopleuric mesenchyme (abdominal wall) expresses keratins, and splanchnopleuric mesenchyme (dorsal mesentery) expresses both keratins and vimentin. While these results are in accordance with most results of keratin and vimentin expression in embryos of other species, they stand against the common concept of keratin and vimentin specificity in adult vertebrate tissues. Furthermore, keratin and vimentin are not expressed in accordance with germ layer origin of tissues in the mammalian embryo; rather the expression of these proteins seems to be related to cellular function during embryonic development.Supported by the Deutsche Forschungsgemeinschaft and by the Netherlands Cancer Foundation 相似文献
96.
Strand specific cleavage of phosphorothioate-containing DNA by reaction with restriction endonucleases in the presence of ethidium bromide. 总被引:6,自引:2,他引:4 下载免费PDF全文
A method for achieving strand specific nicking of DNA has been developed. Phosphorothioate groups were incorporated enzymatically into the (-)strand of M13 RF IV DNA. When such DNA is reacted with restriction endonucleases in the presence of ethidium bromide nicked DNA (RF II) is produced. All of the restriction enzymes tested linearised phosphorothioate-containing DNA in the absence of this dye. The strand specificity of the reaction was investigated by employing the ethidium bromide mediated nicking reaction in the phosphorothioate-based oligonucleotide-directed mutagenesis method. The mutational efficiencies obtained were in the region of 64-89%, indicating that these restriction enzymes hydrolyse the phosphodiester bond at the cleavage site of the unsubstituted (+)strand. 相似文献
97.
98.
Genetics of the quantitative Lp(a) lipoprotein trait 总被引:13,自引:1,他引:12
Gerd Utermann Hans Georg Kraft Hans Jürgen Menzel Thomas Hopferwieser Christoph Seitz 《Human genetics》1988,78(1):41-46
The Lp(a) lipoprotein is a complex particle composed of a low density lipoprotein (LDL)-like lipoprotein and the disulfide bonded Lp(a) glycoprotein. The complex represents a quantitative genetic trait. SDS gel electrophoresis under reducing conditions of sera followed by immunoblotting with affinity-purified polyclonal anti-Lp(a) demonstrated inter- and intra-individual size heterogeneity of the glycoprotein with apparent Mr in the range 400-700kDa. According to their relative mobilities compared to apo B-100 the Lp(a) patterns were categorized into phenotypes F, B, S1, S2, S3 und S4 and into the respective double-band phenotypes. This size heterogeneity seems to be controlled by multiple alleles designated LpF, LpB, LpS1, LpS2, LpS3, LpS4 and a null allele (LpO) at a single locus. Phenotype frequencies observed in 441 unrelated subjects were in good agreement with those expected from the genetic hypothesis. Comparison of Lp(a) lipoprotein concentrations in the different phenotypes revealed a highly significant association of phenotypes B, S1 and S2 with high, and phenotypes S3 und S4 with intermediate Lp(a) concentrations. A third mode is represented by the null phenotype were no Lp(a) band is detected upon immunoblotting and Lp(a) lipoprotein is low or absent. We conclude that the same gene locus is involved in determining Lp(a) glycoprotein phenotype and Lp(a) lipoprotein concentrations in plasma. This major gene seems to be the Lp(a) glycoprotein structural gene locus. 相似文献
99.
Genetics of the quantitative Lp(a) lipoprotein trait 总被引:5,自引:1,他引:4
Summary Lp(a) glycoprotein exhibits an apparent size polymorphism that is associated with genetically controlled Lp(a) lipoprotein concentrations in plasma (Utermann et al. 1988). We have tested the hypothesis that this polymorphism is genetically controlled by studying 15 matings with a total of 44 offspring. This confirmed our conclusion that Lp(a) types are controlled by a series of codominant alleles LpF, LpB, LpS1, LpS2, LpS3 and LpS4 and by a null allele Lpo. Together with the data from the accompanying paper this indicates that the structural gene for the Lp(a) protein is the major gene locus determining Lp(a) lipoprotein concentrations in plasma. 相似文献
100.
Myocyte deenergization and intracellular free calcium dynamics 总被引:1,自引:0,他引:1