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Bourquain H, Schenk A, Prause G, Wald C, Fujimoto Y, Pomfret EA, Tanaka K, Peitgen HO. Abschätzung des intraoperativen Transplantatgewichtes anhand präoperativer Volumetrie bei der Planung der Leberlebendspende. ROFO-FORTSCHR RONTG 2004. [DOI: 10.1055/s-2004-828032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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52
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Frericks BJ, Lehmann KS, Ritz JP, Schenk A, Germer CT, Peitgen HO, Buhr HJ, Wolf KJ. In-vivo Evaluation eines Software-Tools zur semiautomatischen Segmentierung der Lebergefäße im Schweinemodell. ROFO-FORTSCHR RONTG 2004. [DOI: 10.1055/s-2004-828031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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53
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Bourquain H, Hennemuth A, Hindennach M, Schenk A, Ritter F, Peitgen HO. Operations-Planung in der Leberchirurgie. ROFO-FORTSCHR RONTG 2004. [DOI: 10.1055/s-2004-827283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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54
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Rémigy HW, Caujolle-Bert D, Suda K, Schenk A, Chami M, Engel A. Membrane protein reconstitution and crystallization by controlled dilution. FEBS Lett 2003; 555:160-9. [PMID: 14630337 DOI: 10.1016/s0014-5793(03)01105-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Efficient reconstitution of membrane proteins for functional analyses can be achieved by dilution of a ternary mixture containing proteins, lipids and detergents. Once the dilution reaches the point where the free detergent concentration would become lower than the critical micellar concentration, detergent is recruited from the bound detergent pool, and association of proteins and lipids is initiated. Here we show that dilution is also suitable for the assembly of two-dimensional crystals. A device has been designed that allows controlled dilution of a protein-lipid-detergent mixture to induce formation of densely packed or crystalline proteoliposomes. Turbidity is used to monitor the progress of reconstitution on-line, while dilution is achieved by computer-controlled addition of buffer solution in sub-microliter steps. This system has mainly been tested with porin OmpF, a typical beta-barrel protein, and aquaporin-1, a typical alpha-helical protein. The results demonstrate that large, highly ordered two-dimensional crystals can be produced by the dilution method.
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Littmann A, Schenk A, Preim B, Prause G, Lehmann K, Roggan A, Peitgen HO. Planning of anatomical resections and in situ ablations in oncologic liver surgery. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0531-5131(03)00319-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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56
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van Ooijen PMA, Wolf R, Schenk A, Rouw DB, Slooff M, Peitgen HO, Oudkerk M. Recent Developments in Organ-Selective Reconstruction and Analysis of Multiphase Liver CT. ACTA ACUST UNITED AC 2003. [DOI: 10.1046/j.1617-0830.2003.70105.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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57
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Marquenie D, Michiels CW, Geeraerd AH, Schenk A, Soontjen C, Van Impe JF, Nicolaï BM. Using survival analysis to investigate the effect of UV-C and heat treatment on storage rot of strawberry and sweet cherry. Int J Food Microbiol 2002; 73:187-96. [PMID: 11934026 DOI: 10.1016/s0168-1605(01)00648-1] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ultraviolet light and heat treatment are proposed as alternative techniques for the use of chemicals to reduce the development of the spoilage fungi Botrytis cinerea and Monilinia fructigena on strawberry and sweet cherry, respectively, during storage. In order to investigate the effect of both physical techniques on microbial inactivation and on fruit quality, inoculated berries were subjected to different temperatures (40-48 degrees C) and UV-C doses (0.05-1.50 J/cm2). For each condition, 20 berries were used. After the treatment, fungal growth, visual damage (holes, stains) and fruit firmness were evaluated during a period of 10 days. The experimental data were analysed statistically using survival analysis techniques. Fungal growth on strawberries was significantly retarded using UV-C doses of 0.05 J/cm2 and higher. The same treatment had no significant effect when applied to cherries. The highest doses (1.00 and 1.50 J/cm2) had a negative effect on the calyx of the strawberry, causing browning and drying of the leaves. No beneficial effect of a low temperature treatment (40-48 degrees C) on the shelf life of strawberries was observed, but fungal development on cherries was retarded at temperatures of 45 and 48 degrees C. These temperatures caused severe damage on strawberries (soft stains, holes, decreased firmness), but had no influence on the quality of sweet cherries.
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Smirnova A, Li H, Weingart H, Aufhammer S, Burse A, Finis K, Schenk A, Ullrich MS. Thermoregulated expression of virulence factors in plant-associated bacteria. Arch Microbiol 2001; 176:393-9. [PMID: 11734881 DOI: 10.1007/s002030100344] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2001] [Revised: 07/26/2001] [Accepted: 08/14/2001] [Indexed: 11/29/2022]
Abstract
Pathogenic bacteria with habitats inside and outside a given host react to changes in environmental parameters by synthesizing gene products specifically needed during pathogenic or saprophytic growth. Temperature effects have been investigated in detail for pathogens of warm-blooded hosts, and major principles governing the temperature-sensing mechanism have been uncovered. Generally, transcription of virulence genes in these pathogens is induced at higher temperatures (37-41 degrees C), which are typical for body cavities and host tissues. However, effects of temperature on virulence determinants in plant pathogenic bacteria have not been focused on in detail. Interestingly, almost all virulence genes of plant pathogenic bacteria studied with respect to temperature exhibit increased transcription at temperatures well below the respective growth optima. This includes virulence determinants such as those directing bacteria-to-plant gene transfer, plant cell-wall-degrading enzymes, phytotoxins, ice nucleation activity, exopolysaccharide production, and the type III protein secretion machinery. Although many of the studied phytopathogens cause "cold-weather" diseases, the ecological rationale for this phenomenon remains to be studied in detail. This mini-review summarizes our current knowledge on thermoregulation of cellular processes taking place in bacterial phytopathogens in response to temperature changes. Since the temperature range of interest is different from that relevant to pathogens of mammals, one envisions novel principles of thermo-sensing in bacteria interacting with plants.
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Stober HD, Schenk A. [Acute pain therapy in the regional public hospital]. ANAESTHESIOLOGIE UND REANIMATION 2001; 26:32-8. [PMID: 11367876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Pain therapy is an essential component of clinical care. Using the example of a regional hospital, the various possibilities of providing effective pain therapy are discussed. They range from consultations at which patients are given information about their forthcoming anaesthetic to the work done in the recovery room, the surgical departments, the intensive care unit, the delivery room and the emergency department. Taking centre stage among the proven therapies are bolus injections of opiates, continuous infusion of analgetics and pain therapy with patient-controlled pumps or spinal catheters. Proven methods of organising acute pain service are also discussed. The most decisive factor is the degree of patient satisfaction, which can be ensured by measures of quality control.
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Lamb DC, Schenk A, Röcker C, Scalfi-Happ C, Nienhaus GU. Sensitivity enhancement in fluorescence correlation spectroscopy of multiple species using time-gated detection. Biophys J 2000; 79:1129-38. [PMID: 10920042 PMCID: PMC1301008 DOI: 10.1016/s0006-3495(00)76366-1] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Fluorescence correlation spectroscopy (FCS) is a powerful technique to measure chemical reaction rates and diffusion coefficients of molecules in thermal equilibrium. The capabilities of FCS can be enhanced by measuring the energy, polarization, or delay time between absorption and emission of the collected fluorescence photons in addition to their arrival times. This information can be used to change the relative intensities of multiple fluorescent species in FCS measurements and, thus, the amplitude of the intensity autocorrelation function. Here we demonstrate this strategy using lifetime gating in FCS experiments. Using pulsed laser excitation and laser-synchronized gating in the detection channel, we suppress photons emitted within a certain time interval after excitation. Three applications of the gating technique are presented: suppression of background fluorescence, simplification of FCS reaction studies, and investigation of lifetime heterogeneity of fluorescently labeled biomolecules. The usefulness of this technique for measuring forward and backward rates of protein fluctuations in equilibrium and for distinguishing between static and dynamic heterogeneity makes it a promising tool in the investigation of chemical reactions and conformational fluctuations in biomolecules.
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Wybranietz WA, Prinz F, Spiegel M, Schenk A, Bitzer M, Gregor M, Lauer UM. Quantification of VP22-GFP spread by direct fluorescence in 15 commonly used cell lines. J Gene Med 2000. [PMID: 10738559 DOI: 10.1002/(sici)1521-2254(199907/08)1:4<265::aid-jgm48>3.0.co;2-d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND The intercellular transport property of VP22 chimeric proteins offers the opportunity for the improvement of gene therapy delivery systems. Since enhanced therapeutic effects of transduced genes already have been exemplified for chimeric proteins VP22-p53 and VP22-tk, we were interested in examining whether spread of VP22 chimeric proteins is a general biological phenomenon not restricted to distinct tissues or species. METHODS To study intercellular spread of VP22-GFP fusion proteins, 15 different mammalian cell lines were transfected with 200-2000 ng of VP22-GFP or GFP expression plasmids. Expression of VP22-GFP or GFP was monitored by fluorescence microscopy of live GFP fluorescence and direct FACS analysis. For selected cell lines, antibody detection of VP22-GFP spread was analysed by confocal microscopy as a control. RESULTS Spread of VP22-GFP fusion proteins was detected in all 15 cell lines tested, and quantified by FACS analysis. Experimental conditions were found to be critical in the investigation of VP22-mediated intercellular spread. CONCLUSION Results of our study indicate that spread of VP22 chimeric proteins is a general biological phenomenon not restricted to distinct tissues or species. Therefore, further evidence is provided that VP22-enhanced gene therapeutic effects may be obtained irrespective of the target organ/tissue to be addressed.
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Wybranietz WA, Prinz F, Spiegel M, Schenk A, Bitzer M, Gregor M, Lauer UM. Quantification of VP22-GFP spread by direct fluorescence in 15 commonly used cell lines. J Gene Med 1999; 1:265-74. [PMID: 10738559 DOI: 10.1002/(sici)1521-2254(199907/08)1:4<265::aid-jgm48>3.0.co;2-d] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND The intercellular transport property of VP22 chimeric proteins offers the opportunity for the improvement of gene therapy delivery systems. Since enhanced therapeutic effects of transduced genes already have been exemplified for chimeric proteins VP22-p53 and VP22-tk, we were interested in examining whether spread of VP22 chimeric proteins is a general biological phenomenon not restricted to distinct tissues or species. METHODS To study intercellular spread of VP22-GFP fusion proteins, 15 different mammalian cell lines were transfected with 200-2000 ng of VP22-GFP or GFP expression plasmids. Expression of VP22-GFP or GFP was monitored by fluorescence microscopy of live GFP fluorescence and direct FACS analysis. For selected cell lines, antibody detection of VP22-GFP spread was analysed by confocal microscopy as a control. RESULTS Spread of VP22-GFP fusion proteins was detected in all 15 cell lines tested, and quantified by FACS analysis. Experimental conditions were found to be critical in the investigation of VP22-mediated intercellular spread. CONCLUSION Results of our study indicate that spread of VP22 chimeric proteins is a general biological phenomenon not restricted to distinct tissues or species. Therefore, further evidence is provided that VP22-enhanced gene therapeutic effects may be obtained irrespective of the target organ/tissue to be addressed.
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63
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Bouton N, Witte F, Alphen JJMV, Schenk A, Seehausen O. Local adaptations in populations of rock–dwelling haplochromines (Pisces:Cichlidae) from southern Lake Victoria. Proc Biol Sci 1999. [DOI: 10.1098/rspb.1999.0645] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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64
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Spiegel M, Bitzer M, Schenk A, Rossmann H, Neubert WJ, Seidler U, Gregor M, Lauer U. Pseudotype formation of Moloney murine leukemia virus with Sendai virus glycoprotein F. J Virol 1998; 72:5296-302. [PMID: 9573308 PMCID: PMC110129 DOI: 10.1128/jvi.72.6.5296-5302.1998] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/1997] [Accepted: 02/18/1998] [Indexed: 02/07/2023] Open
Abstract
Mixed infection of cells with both Moloney murine leukemia virus (MoMLV) and related or heterologous viruses produces progeny pseudotype virions bearing the MoMLV genome encapsulated by the envelope of the other virus. In this study, pseudotype formation between MoMLV and the prototype parainfluenza virus Sendai virus (SV) was investigated. We report for the first time that SV infection of MoMLV producer cells results in the formation of MoMLV(SV) pseudotypes, which display a largely extended host range compared to that of MoMLV particles. This could be associated with SV hemagglutinin-neuraminidase (SV-HN) glycoprotein incorporation into MoMLV envelopes. In contrast, solitary incorporation of the other SV glycoprotein, SV fusion protein (SV-F), resulted in a distinct and narrow extension of the MoMLV host range to asialoglycoprotein receptor (ASGP-R)-positive cells (e.g., cultured human hepatoma cells). Since stably ASGP-R cDNA-transfected MDCK cells, but not parental ASGP-R-negative MDCK cells, were found to be transduced by MoMLV(SV-F) pseudotypes and transduction of ASGP-R-expressing cells was found to be inhibited by ASGP-R antiserum, a direct proof for the ASGP-R-restricted tropism of MoMLV(SV-F) pseudotypes was provided. Cultivation of ASGP-R-positive HepG2 hepatoma cells on Transwell-COL membranes led to a significant enhancement of MoMLV(SV-F) titers in subsequent flowthrough transduction experiments, thereby suggesting the importance of ASGP-R accessibility at the basolateral domain for MoMLV(SV-F) pseudotype transduction. The availability of such ASGP-R-restricted MoMLV(SV-F)-pseudotyped vectors opens up new perspectives for future liver-restricted therapeutic gene transfer applications.
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Schenk A, Kovacs KM. Genetic Variation in a Population of Black Bears as Revealed by DNA Fingerprinting. J Mammal 1996. [DOI: 10.2307/1382776] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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66
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Cross J, Bonauer A, Bondio V, Clemente J, Denis J, Grauslund J, Huguet C, Jörg E, Koning S, Kvale A, Malavolta C, Marcelle R, Morandell I, Oberhofer H, Pontalti M, Polesny F, Rossini M, Schenk A, de Schaetzen C, Vilajeliu M. THE CURRENT STATUS OF INTEGRATED POME FRUIT PRODUCTION IN WESTERN EUROPE AND ITS ACHIEVEMENTS. ACTA ACUST UNITED AC 1996. [DOI: 10.17660/actahortic.1996.422.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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67
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Lutterloh C, Biener J, Schenk A, Küppers J. Interaction of D(H) atoms with physisorbed benzene and (1,4)‐dimethyl‐cyclohexane: Hydrogenation and H abstraction. J Chem Phys 1996. [DOI: 10.1063/1.470934] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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68
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Nyffeler A, Schenk A. Effective field theory for a heavy Higgs boson: A manifestly gauge-invariant approach. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1996; 53:1494-1507. [PMID: 10020140 DOI: 10.1103/physrevd.53.1494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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69
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Petzinger E, Blumrich M, Brühl B, Eckhardt U, Föllmann W, Honscha W, Horz JA, Müller N, Nickau L, Ottallah-Kolac M, Platte HD, Schenk A, Schuh K, Schulz K, Schulz S. What we have learned about bumetanide and the concept of multispecific bile acid/drug transporters from the liver. J Hepatol 1996; 24 Suppl 1:42-6. [PMID: 8926368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Bumetanide is a weak organic acid which is transported into hepatocytes by a transport system that is related neither to the cloned sodium-dependent taurocholate cotransporting polypeptide Ntcp nor to the cloned organic anion transporting polypeptide oatp. Bumetanide is known to be transported in the kidney by a multispecific organic anion transporter which is the pAH-transporter from the proximal tubule cell. In the liver, bumetanide uptake competes with bile acid uptake, indicating a functionally related multispecific transporter for bile acids and drugs in hepatocytes. This multispecific bile acid transporter MBAT has not been cloned yet. When basolateral membranes were photoaffinity labeled with [3H]bumetanide, several bumetanide binding proteins were separated and identified after protein sequencing from two-dimensional electrophoresis gels.
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Georgi H, Kaplan L, Morin D, Schenk A. Effects of top quark compositeness. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1995; 51:3888-3894. [PMID: 10018856 DOI: 10.1103/physrevd.51.3888] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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71
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Adibzadeh M, Friccius H, Bornhak S, Max H, Hambrecht A, Sansom D, Kalbacher H, Schenk A, Pohla H, Pawelec G. Role of three quantitatively dominant endogenous peptides from HLA-DRB1*0401 molecules in class II specific alloreactivity. Transpl Immunol 1994; 2:293-9. [PMID: 7704539 DOI: 10.1016/0966-3274(94)90005-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Alloreactivity remains an important barrier to organ transplantation and is caused by T cell recognition of foreign histocompatibility antigens (HAg) in two ways: (1) indirect recognition, in which processed HAg peptides are presented by self MHC like any other foreign antigen, and (2) direct recognition, where the foreign MHC itself is recognized in contravention of the T cell recognition rule of self restriction. Whereas the role of endogenous peptides in direct MHC class I specific recognition is now established, their role in class II specific direct alloreactivity remains controversial, since no defined endogenous peptide has been shown to be required for alloreactivity. That mutations resulting in defective antigen processing impair class II specific allostimulation, however, suggests that the endogenous pathway is important for class II as well as class I alloreactivity. We attempted to establish the importance of endogenous peptides for alloreactivity by identifying common sequences of peptides bound by DR molecules of an HLA-DRB1*0401 homozygous B cell line. Peptides corresponding to three of these (calreticulin, HLA class I and an unidentified molecule) were used to restimulate established allospecific HLA-Dw4 reactive T cell clones, as well as to sensitize allogeneic T cells de novo in vitro. Xenogeneic chinese hamster ovary (CHO) cells coexpressing the relevant DR allele together with CD80 were used as antigen presenting cells. The role of CD80 could be determined on these cells because (1) they are xenogeneic and (2) they do not express B7 family members bound by CTLA-4Ig.(ABSTRACT TRUNCATED AT 250 WORDS)
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Horn A, Schenk A, Biener J, Winter B, Lutterloh C, Wittmann M, Küppers J. H atom impact induced chemical erosion reaction at C:H film surfaces. Chem Phys Lett 1994. [DOI: 10.1016/0009-2614(94)01233-4] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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73
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Biener J, Schenk A, Winter B, Schubert UA, Lutterloh C, Küppers J. Spectroscopic investigation of electronic and vibronic properties of ion-beam-deposited and thermally treated ultrathin C:H films. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:17307-17318. [PMID: 10010912 DOI: 10.1103/physrevb.49.17307] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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74
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Adibzadeh M, Bühring HJ, Daikeler T, Siegels-Hübenthal P, Owsianowsky M, Schenk A, Rehbein A, Schaudt K, Schlotz E, Pohla H. Extrathymic development and function of human T-lymphocytes from bone marrow cells in vitro. Cell Immunol 1994; 154:25-42. [PMID: 8118889 DOI: 10.1006/cimm.1994.1054] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To enrich low-density human bone marrow (BM) cells for putative progenitors of T-lymphocytes, CD7+ CD3- cells were sorted (purity was estimated at > 99.9%) and cultured under limiting dilution conditions with irradiated allogeneic stimulator cells, interleukin (IL) 2, and PHA. Clonal populations were available for analysis from Day 25 onward. By this time, all clones (n = 54) expressed CD3 and alpha/beta-T cell receptor (TCR2). Fifty percent of the clones were CD4+ and 50% were CD8+, with no double positives, whereas almost all clones obtained under identical conditions from peripheral blood (PB) cells were CD4+. All clones were capable of autocrine proliferation, which was blocked by CD25 or CD71 mAb. Most or all clones tested (n = 15) responded to IL 4 and IL 7 as well as IL 2, but not to IL 3 or GM-CSF and only two responded to IL 9. Most clones accumulated mRNA for GM-CSF, IL 2, IL 3, IL 4, IL 5 and also IL 9, but 6 of 11 were negative for IFN-gamma mRNA, and all were negative for IL 6 mRNA. Sixty-two percent of CD4+ and 85% of CD8+ clones (total 70% of all clones) mediated lectin-dependent cell lysis; but whereas 35% of CD4+ and 65% of CD8+ clones (total 46% of all clones) lysed K562 natural killer (NK)-susceptible targets, only 24% of CD4+ and 5% of CD8+ clones (total 17% of all clones) killed lymphokine-activated killer (LAK)-susceptible Daudi cells. Only three clones lysed allogeneic LCL targets and none lysed autologous targets. Furthermore, none of the clones proliferated when stimulated by autologous cells, neither did they suppress proliferative responses of autologous cells. These results suggest that CD3- cells from the bone marrow can acquire functional cytotoxic and proliferative programs extrathymically during in vitro culture with IL 2, mitogens and allogeneic cells, but do not manifest autoreactivity in the three test systems, cytotoxicity, suppression, or autocrine proliferation.
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75
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Biener J, Schubert UA, Schenk A, Winter B, Lutterloh C, Küppers J. A surface reaction with atoms: Hydrogenation of sp‐ and sp2‐hybridized carbon by thermal H(D) atoms. J Chem Phys 1993. [DOI: 10.1063/1.465166] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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