Abstract:
:Recombinant full-length CD4 expressed in Spodoptera frugiperda 9 cells with the baculovirus system was electroinserted in erythrocyte (RBC) membranes. Of the inserted CD4, 70% was "correctly" oriented as shown by fluorescence quenching experiments with fluorescein-labeled CD4. The inserted CD4 displayed the same epitopes as the naturally occurring CD4 in human T4 cells. Double-labeling experiments (125I-CD4 and 51Cr-RBC) showed that the half-life of CD4 electroinserted in RBC membrane in rabbits was approximately 7 days. Using the fluorescence dequenching technique with octadecylrhodamine B-labeled human immunodeficiency virus (HIV)-1, we showed fusion of the HIV envelope with the plasma membrane of RBC-CD4, whereas no such fusion could be detected with RBC. The dequenching efficiency of RBC-CD4 is the same as that of CEM cells. Exposure to anti-CD4 monoclonal antibody OKT4A, which binds to the CD4 region that attaches to envelope glycoprotein gp120, caused a significant decrease in the dequenching of fluorescence. In vitro infectivity studies showed that preincubation of HIV-1 with RBC-CD4 reduced by 80-90% the appearance of HIV antigens in target cells, the amount of viral reverse transcriptase, and the amount of p24 core antigen produced by the target cells. RBC-CD4, but not RBCs, aggregated with chronically HIV-1-infected T cells and caused formation of giant cells. These data show that the RBC-CD4 reagent is relatively long lived in circulation and efficient in attaching to HIV-1 and HIV-infected cells, and thus it may have value as a therapeutic agent against AIDS.
journal_name
Proc Natl Acad Sci U S Aauthors
Zeira M,Tosi PF,Mouneimne Y,Lazarte J,Sneed L,Volsky DJ,Nicolau Cdoi
10.1073/pnas.88.10.4409subject
Has Abstractpub_date
1991-05-15 00:00:00pages
4409-13issue
10eissn
0027-8424issn
1091-6490journal_volume
88pub_type
杂志文章abstract::The SCF ubiquitin ligase complex of budding yeast triggers DNA replication by catalyzing ubiquitination of the S phase cyclin-dependent kinase inhibitor SIC1. SCF is composed of three proteins-ySKP1, CDC53 (Cullin), and the F-box protein CDC4-that are conserved from yeast to humans. As part of an effort to identify co...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.13.7451
更新日期:1998-06-23 00:00:00
abstract::[3H]Puromycin and N-(ethyl-2-diazomalonyl)[3H]puromycin are incorporated into E. coli ribosomes on irradiation at 253.7 nm. Both compounds incorporate into both protein and nucleic acid. Two-dimensional gel electrophoresis of ribosomal protein shows that L23 is the major protein labeled by puromycin. Although incorpor...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.72.8.2974
更新日期:1975-08-01 00:00:00
abstract::An emergent viral pathogen termed severe fever with thrombocytopenia syndrome virus (SFTSV) is responsible for thousands of clinical cases and associated fatalities in China, Japan, and South Korea. Akin to other phleboviruses, SFTSV relies on a viral glycoprotein, Gc, to catalyze the merger of endosomal host and vira...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1603827113
更新日期:2016-06-28 00:00:00
abstract::Routine dietary consumption of foods that contain aflatoxins is the second leading cause of environmental carcinogenesis worldwide. Aflatoxin-driven mutagenesis is initiated through metabolic activation of aflatoxin B1 (AFB1) to its epoxide form that reacts with N7 guanine in DNA. The resulting AFB1-N7-dG adduct under...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1609024113
更新日期:2016-11-29 00:00:00
abstract::Frogs (Anura) are one of the most diverse groups of vertebrates and comprise nearly 90% of living amphibian species. Their worldwide distribution and diverse biology make them well-suited for assessing fundamental questions in evolution, ecology, and conservation. However, despite their scientific importance, the evol...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1704632114
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0807411105
更新日期:2008-10-07 00:00:00
abstract::The deadly symptoms of malaria occur as Plasmodium parasites replicate within blood cells. Members of several variant surface protein families are expressed on infected blood cell surfaces. Of these, the largest and most ubiquitous are the Plasmodium-interspersed repeat (PIR) proteins, with more than 1,000 variants in...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.2016775117
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2009-03-17 00:00:00
abstract::In both Escherichia coli and Salmonella typhimurium there is approximately balanced synthesis of the six catalytic and six regulatory polypeptide chains of the regulatory enzyme aspartate transcarbamoylase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2). This control is achieved by the contiguous pyr...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.13.4020
更新日期:1982-07-01 00:00:00
abstract::Activation of the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway is a frequent occurrence in human cancers and a major promoter of chemotherapeutic resistance. Inhibition of one downstream target in this pathway, mTORC1, has shown potential to improve chemosensitivity. However, the mechanisms and genetic m...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0804821105
更新日期:2008-08-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.192467799
更新日期:2002-09-17 00:00:00
abstract::The all-cis hexose D-allose, fed to hamster fibroblast cultures over 14-20 hr, brings about a striking down-regulation of hexose transport. This down-regulation by allose is inhibited by 2,4-dinitrophenol. By using D-[14C]allose and thin-layer chromatography, two types of products accumulated that have been identified...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.4.1504
更新日期:1991-02-15 00:00:00
abstract::Two-electron oxidation of cobaltous octaethylporphyrin [Co(II)(Et)(8)P] yields a stable pi-cation radical [Co(III)(Et)(8)P](2+.), the optical spectrum of which exhibits spectral changes dependent upon the nature of the counterion. Comparison of these spectra with those of Compounds I of horseradish peroxidase and cata...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.68.3.614
更新日期:1971-03-01 00:00:00
abstract::Human skin and lung mast cells and rodent peritoneal mast cells contain a carboxypeptidase in their secretory granules. We have screened human lung cDNA libraries with a mouse mast cell carboxypeptidase A (MC-CPA) cDNA probe to isolate a near-full-length cDNA that encodes human MC-CPA. The 5' end of the human MC-CPA t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.23.9480
更新日期:1989-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0712398105
更新日期:2008-05-27 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0501451102
更新日期:2005-07-05 00:00:00
abstract::The 1,25-dihydroxyvitamin D3 [1,25-(OH)2vitamin D3] analog KH1060 exerts very potent effects on cell proliferation and cell differentiation via the vitamin D receptor (VDR). However, the activities of KH1060 are not associated with an increased affinity for the VDR. We now show that increased stabilization of the VDR-...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.93.20.10685
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1997-08-05 00:00:00
abstract::In our earlier work we showed that either spermidine or spermine could support the growth of spe2Delta or spe3Delta polyamine-requiring mutants, but it was unclear whether the cells had a specific requirement for either of these amines. In the current work, we demonstrate that spermidine is specifically required for t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2003-11-25 00:00:00
abstract::Stem cell therapy has emerged as a promising tool for the treatment of a variety of diseases. Previously, we have shown that Akt-modified mesenchymal stem cells mediate tissue repair through paracrine mechanisms. Using a comprehensive functional genomic strategy, we show that secreted frizzled related protein 2 (Sfrp2...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0610024104
更新日期:2007-01-30 00:00:00
abstract::Epigenetic markers, such as histone acetylation and DNA methylation, determine chromatin organization. In eukaryotic cells, metabolites from organelles or the cytosol affect epigenetic modifications. However, the relationships between metabolites and epigenetic modifications are not well understood in plants. We found...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1904143116
更新日期:2019-05-21 00:00:00
abstract::Thymidine kinase-deficient mouse L cells have been transformed with plasmid DNAs carrying 8-base-pair Xho I linker insertion mutations in the coding region of the herpes simplex virus type 1 thymidine kinase gene. When the mutant plasmids are introduced individually into LTK- cells, transformation efficiencies are gre...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.15.4827
更新日期:1983-08-01 00:00:00
abstract::Epidermal growth factor (EGF) stimulates membrane protein phosphorylation in a human cell line, A-431. The known hepatic mitogenic action of EGF and the reduction in EGF receptor number that occurs during liver regeneration led us to study whether EGF-dependent protein kinase activity was present in rat liver and whet...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.3.776
更新日期:1982-02-01 00:00:00
abstract::Hypothalamic malonyl-CoA has been shown to function in global energy homeostasis by modulating food intake and energy expenditure. Little is known, however, about the regulation of malonyl-CoA concentration in the central nervous system. To address this issue we investigated the response of putative intermediates in t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2007-12-04 00:00:00
abstract::Clonal deletion provides an important mechanism for the elimination of autoreactive T cells. Deletion is accomplished by programmed cell death directed by interaction of the T-cell receptor (TCR) of the developing thymocyte with major histocompatibility complex elements in the thymic environment. In this report we pre...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.6.2151
更新日期:1991-03-15 00:00:00
abstract::The interrelationships of hexose feeding and insulin action were studied in the Chinese hamster fibroblast cell lines 023 and DS-7. The latter, derived from 023 and deficient in phosphoglucose isomerase, has been used to map the metabolic requirements for aldohexose-mediated down-regulation or "curbing" of hexose tran...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.11.3684
更新日期:1986-06-01 00:00:00
abstract::The Arabidopsis thaliana disease resistance genes RPS2 and RPM1 belong to a class of plant disease resistance genes that encode proteins that contain an N-terminal tripartite nucleotide binding site (NBS) and a C-terminal tandem array of leucine-rich repeats. RPS2 and RPM1 confer resistance to strains of the bacterial...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.26.15497
更新日期:1996-12-24 00:00:00
abstract::Analysis of the nucleotide and deduced amino acid sequences of the biologically active mouse mdr1 cDNA clone indicates that the protein is formed by two highly homologous halves, each containing six putative transmembrane domains and a nucleotide-binding site. The duplicated unit shows high sequence homology to the pr...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.17.6488
更新日期:1989-09-01 00:00:00