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001-es BibID:	BIBFORM020768
Első szerző:	Roszik János (biofizikus)
Cím:	T-cell synapse formation depends on antigen recognition but not CD3 interaction : studies with TCR : zeta, a candidate transgene for TCR gene therapy / Roszik J., Sebestyén Z., Govers C., Guri Y., Szöor A., Pályi-Krekk Z., Vereb G., Nagy P., Szöllosi J., Debets R.
Dátum:	2011
Megjegyzések:	T-cell receptors (TCRs) can be genetically modified to improve gene-engineered T-cell responses, a strategy considered critical for the success of clinical TCR gene therapy to treat cancers. TCR:zeta, which is a heterodimer of TCRalpha and beta chains each coupled to complete human CD3zeta, overcomes issues of mis-pairing with endogenous TCR chains, shows high surface expression and mediates antigen-specific T-cell functions in vitro. In the current study, we further characterized TCR:zeta in gene-engineered T cells and assessed whether this receptor is able to interact with surface molecules and drive correct synapse formation in Jurkat T cells. The results showed that TCR:zeta mediates the formation of synaptic areas with antigen-positive target cells, interacts closely with CD8alpha and MHC class I (MHCI), and co-localizes with CD28, CD45 and lipid rafts, similar to WT TCR. TCR:zeta did not closely associate with endogenous CD3epsilon, despite its co-presence in immune synapses, and TCR:zeta showed enhanced synaptic accumulation in T cells negative for surface-expressed TCR molecules. Notably, synaptic TCR:zeta demonstrated lowered densities when compared with TCR in dual TCR T cells, a phenomenon that was related to both extracellular and intracellular CD3zeta domains present in the TCR:zeta molecule and responsible for enlarged synapse areas
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Adoptive Transfer Antigens Antigens,CD28 Antigens,CD3 Antigens,CD45 Antigens,CD8 article Biophysics Cells Flow Cytometry Gene Therapy genetics Histocompatibility Antigens Histocompatibility Antigens Class I Human Humans Hungary Immunity,Cellular Immunological Synapses immunology In Vitro Jurkat Cells lipid raft LIPID RAFTS Membrane Microdomains metabolism physiology Receptor-CD3 Complex,Antigen,T-Cell Receptors,Antigen,T-Cell,alpha-beta Research Research Support Support Synapses T-Lymphocytes therapy Transgenes
Megjelenés:	European Journal of Immunology. - 41 : 5 (2011), p. 1288-1297. -
További szerzők:	Sebestyén Zsolt Govers, Coen Guri, Yakir Szöőr Árpád (1984-) (orvos) Pályiné Krekk Zsuzsanna (1974-) (molekuláris biológus) Vereb György (1965-) (biofizikus, orvos) Nagy Péter (1971-) (biofizikus) Szöllősi János (1953-) (biofizikus) Debets, Reno
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM039658
035-os BibID:	(scopus)0036628631 (wos)000176656500002
Első szerző:	Sebestyén Zsolt
Cím:	Long wavelength fluorophores and cell-by-cell correction for autofluorescence significantly improves the accuracy of flow cytometric energy transfer measurements on a dual-laser benchtop flow cytometer / Zsolt Sebestyén, Péter Nagy, Gábor Horváth, György Vámosi, Reno Debets, Jan W. Gratama, Denis R. Alexander, János Szöllősi
Dátum:	2002
ISSN:	0196-4763
Megjegyzések:	Flow cytometric fluorescence resonance energy transfer (FCET) is an efficient method to map associations between biomolecules because of its high sensitivity to changes in molecular distances in the range of 1-10 nm. However, the requirement for a dual-laser instrument and the need for a relatively high signal-to-noise system (i.e., high expression level of the molecules) pose limitations to a wide application of the method.METHODS:Antibodies conjugated to cyanines 3 and 5 (Cy3 and Cy5) were used to label membrane proteins on the cell surface. FCET measurements were made on a widely used benchtop dual-laser flow cytometer, the FACSCalibur, by using cell-by-cell analysis of energy transfer efficiency.ResultsTo increase the accuracy of FCET measurements, we applied a long wavelength donor-acceptor pair, Cy3 and Cy5, which beneficially affected the signal-to-noise ratio in comparison with the classic pair of fluorescein and rhodamine. A new algorithm for cell-by-cell correction of autofluorescence further improved the sensitivity of the technique; cell subpopulations with only slightly different FCET efficiencies could be identified. The new FCET technique was tested on various direct and indirect immunofluorescent labeling strategies. The highest FCET values could be measured when applying direct labeling on both (donor and acceptor) sides. Upon increasing the complexity of the labeling scheme by introducing secondary antibodies, we detected a decrease in the energy transfer efficiency.CONCLUSIONS:We developed a new FCET protocol by applying long wavelength excitation and detection of fluorescence and by refining autofluorescence correction. The increased accuracy of the new method makes cells with low receptor expression amenable to FCET investigation, and the new approach can be implemented easily on a commercially available dual-laser flow cytometer, such as a FACSCalibur.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Algorithms analysis Antibodies Biophysics Calibration Cell Line, Transformed Cells Comparative Study Dyes Energy Transfer Flow Cytometry Fluorescein Fluorescence Fluorescence Resonance Energy Transfer Fluorescent Dyes Humans Hungary instrumentation Lasers Membrane Proteins methods Proteins Reproducibility of Results Research Spectrometry, Fluorescence Subtraction Technique Support Tumor Cells, Cultured egyetemen (Magyarországon) készült közlemény
Megjelenés:	Cytometry. - 48 : 3 (2002), p. 124-135. -
További szerzők:	Nagy Péter (1971-) (biofizikus) Horváth Gábor (1974-) (biofizikus) Vámosi György (1967-) (biofizikus) Debets, Reno Gratama, Jan Willem Alexander, Denis R. Szöllősi János (1953-) (biofizikus)
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