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381.
The therapeutic use of T cell receptor (TCR)-transduced peripheral blood lymphocytes (PBL) targeting tumor-associated antigens is emerging as a promising investigational treatment for patients with cancer. Initial response rates to therapy were low, suggesting the need to improve the function of TCR-transduced PBL. We constructed standard bicistronic retroviral vectors using an internal promoter or internal ribosomal entry site element as well as vectors incorporating coding sequences for 2A linker peptides between coding sequences for α and β chains targeting the cancer-testis (CT) antigen, NY-ESO-1. Incorporation of coding sequences for 2A linker peptides in the bicistronic TCR expression cassette resulted in up to a fourfold increase in TCR expression and a significant improvement in effector function as measured by interferon-gamma release following co-culture with peptide-pulsed targets and NY-ESO-1+ tumors. We also sought to enhance reactivity of TCR-transduced PBL against tumor targets by modulation of tumor antigen expression on target cells. Induction of NY-ESO-1 expression on tumor targets using the demethylating agent 5-aza-2′-deoxycytidine (alone or in combination with the histone deacetylase inhibitor depsipeptide) resulted in enhanced interferon-gamma secretion by the TCR-transduced PBL on culture with treated targets. Taken together, these results indicate that design of TCR-based vectors incorporating 2A linker peptides improves TCR expression and effector function of transduced PBL. Furthermore, induction of CT antigen expression through treatment of tumor targets with chromatin-remodeling agents may augment TCR-based immunotherapy targeting these antigens. These results have relevance for TCR-based gene therapies targeting common epithelial malignancies. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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The purpose of this study was to contribute to concept clarification regarding identification of the Type A behavior pattern in children. To accomplish this, two measurement techniques for assessing Type A behavior in children (MYTH and Hunter-Wolf) were compared to a third (a teacher-rated measure of hyperactivity: the Conners), since this latter measure, although often used to diagnose hyperactive children, seemed also to measure some Type A-like behaviors. The Hunter-Wolf also included a self-assessment of Type A behavior. The conceptual and measurement issue was: Are teachers rating Type A or hyperactive/problem behaviors in children? Fifty-five teachers participated. They rated 253 students, aged 8 to 17 years, in a biracial community. The clear overlap between teacher-assessed Type A and the Conners hyperactivity measure was demonstrated when the best predictor of teacher-assessed Type A measure was the Conners. This was especially true for black males and white females. Little relationship existed between teacher-assessed Type A and self-assessment. The conclusions suggest that implications drawn from teacher-assessed Type A behavior in children may be inadequate because of potential ethnic and gender artifactual measurement error.  相似文献   
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Skim milks containing sodium chloride (0.75m) were centrifuged at 80000g for 2hr. and portions of the supernatants were submitted to gel filtration on columns of Sephadex G-200. Enzymes in the effluent fractions were assayed titrimetrically for their hydrolytic activities towards tributyrin, triolein and milk-fat emulsions, and triacetin solution. Summation of the measurements gave ratios of activities towards the various substrates similar to those of the original skim milks. Although only partial separation was obtained, five enzymes appeared to be present. They showed some differences in substrate specificity, but all appeared to be lipases in that they hydrolysed the emulsified substrates more rapidly than the dissolved triacetin.  相似文献   
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The mechanisms responsible for initiating the conversion of globular to filamentous actin (assembly) after stimulation of B lymphocytes and the role of these cytoskeletal changes in cell activation are incompletely understood. We investigated the molecular basis of the signals leading to actin polymerization and concentrated on the involvement of guanosine triphosphate (GTP)-binding regulatory proteins, and protein kinase C (PKC). In addition, we related these early events to later events in B-cell activation, including cell proliferation. Cross-linking the Ag receptor with Staphylococcus aureus Cowan I (SAC) or anti-IgM antibodies, or stimulation of PKC with phorbol ester induced a time- and concentration-dependent increase in the filamentous actin content of B cells. Inhibition or depletion of PKC resulted in decreased actin assembly induced by anti-IgM, SAC, and PMA, suggesting that the signal for polymerization is generated distally to PKC activation. Pertussis toxin pretreatment inhibited the responses to anti-IgM and SAC but not PMA, and direct stimulation of permeabilized cells with GTP gamma S induced microfilament assembly, indicating the involvement of a GTP-binding protein for receptor-mediated events. Disruption of actin polymerization with botulinum C2 toxin or cytochalasin D inhibited the assembly of actin and [3H]TdR incorporation induced by all stimuli. We conclude that human B cell activation by receptor-mediated stimuli results in actin polymerization by signaling pathways coupled to GTP-binding proteins. These changes in the cytoskeleton may be involved in the transduction of messages leading to responses such as proliferation in B lymphocytes.  相似文献   
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Skeletal muscle stretch increases resting metabolism and causes hypertrophy. We have examined the effect of mechanical stretch in vitro on glucose transport activity and transporter contents in L6 muscle cells. Long-term (24-48 h) stretch-relaxation (25% maximal elongation at 30 cycles per min) of cell monolayers significantly increased glucose uptake by 1.6- to 2-fold in myotubes but not in myoblasts. The presence of serum was required for the stretch-relaxation induced increase in glucose uptake. Cycloheximide inhibited the mechanical stimulation of glucose uptake, and the latter response was not additive to the stimulatory effect of long-term exposure to insulin. GLUT1 and GLUT4 glucose transporter contents were not changed in total cell membranes from mechanically stimulated cells relative to controls. These results indicate that mechanical stimulation through passive stretch may be an important regulation of nutrient uptake in fetal myotubes independent of innervation.  相似文献   
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