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001-es BibID:	BIBFORM059572
Első szerző:	Bene László (biofizikus)
Cím:	Nanoparticle energy transfer on the cell surface / László Bene, Gergely Szentesi, László Mátyus, Rezső Gáspár, Sándor Damjanovich
Dátum:	2005
ISSN:	0952-3499
Megjegyzések:	Membrane topology of receptors plays an important role in shaping transmembrane signalling of cells. Among the methods used for characterizing receptor clusters, fluorescence resonance energy transfer between a donor and acceptor fluorophore plays a unique role based on its capability of detecting molecular level (2-10 nm) proximities of receptors in physiological conditions. Recent development of biotechnology has made possible the usage of colloidal gold particles in a large size range for specific labelling of cells for the purposes of electron microscopy. However, by combining metal and fluorophore labelling of cells, the versatility of metal-fluorophore interactions opens the way for new applications by detecting the presence of the metal particles by the methods of fluorescence spectroscopy. An outstanding feature of the metal nanoparticle-fluorophore interaction is that the metal particle can enhance spontaneous emission of the fluorophore in a distance-dependent fashion, in an interaction range essentially determined by the size of the nanoparticle. In our work enhanced fluorescence of rhodamine and cyanine dyes was observed in the vicinity of immunogold nanoparticles on the surface of JY cells in a flow cytometer. The dyes and the immunogold were targetted to the cell surface receptors MHCI, MHCII, transferrin receptor and CD45 by monoclonal antibodies. The fluorescence enhancement was sensitive to the wavelength of the exciting light, the size and amount of surface bound gold beads, as well as the fluorophore-nanoparticle distance. The intensity of 90 degrees scattering of the incident light beam was enhanced by the immunogold in a concentration and size-dependent fashion. The 90 degrees light scattering varied with the wavelength of the incident light in a manner characteristic to gold nanoparticles of the applied sizes. A reduction in photobleaching time constant of the cyanine dye was observed in the vicinity of gold particles in a digital imaging microscope. Modulations of 90 degrees light scattering intensity and photobleaching time constant indicate the role of the local field in the fluorescence enhancement. A mathematical simulation based on the electrodynamic theory of fluorescence enhancement showed a consistency between the measured enhancement values, the inter-epitope distances and the quantum yields. The feasibility of realizing proximity sensors operating at distance ranges larger than that of the conventional Forster transfer is demonstrated on the surface of living cells
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Antibodies Antibodies,Monoclonal Antigens,CD45 B-Lymphocytes Biophysics Carbocyanines Cell Membrane Cells Cultured chemistry diagnostic use Dyes Energy Transfer Fluorescence Fluorescent Dyes Gold Humans Hungary immunology Light metabolism methods Microscopy Nanotechnology Photobleaching Receptors,Transferrin Research Rhodamines Spectrometry,Fluorescence Support
Megjelenés:	Journal Of Molecular Recognition. - 18 : 3 (2005), p. 236-253. -
További szerzők:	Szentesi Gergely (1976-) (kémia-fizika tanár) Mátyus László (1956-) (biofizikus) Gáspár Rezső (1944-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
Pályázati támogatás:	OTKA-T042618 OTKA OTKA-TS040773 OTKA OTKA-T043509 OTKA OTKA-T043087 OTKA
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM057877
Első szerző:	Gogolák Péter (biológus, immunológus)
Cím:	Targeting dendritic cells for priming cellular immune responses / Péter Gogolák, Bence Réthi, György Hajas, Éva Rajnavölgyi
Dátum:	2003
ISSN:	0952-3499
Megjegyzések:	The cardinal role of dendritic cells (DC) in priming adaptive immunity and in orchestrating immune responses against all classes of pathogens and also against tumors is well established. Their unique potential both to maintain self-tolerance and to initiate protective immune responses against foreign and/or dangerous structures is based on the functional diversity and flexibility of these cells. Tissue DC lining antigenic portals such as mucosal surfaces and the skin are specialized to take up a wide array of compounds including proteins, lipids, carbohydrates, glycoproteins, glycolipids and oligonucleotides, particles carrying such structures and apoptotic or necrotic cells. This process is facilitated by specialized receptors with high endocytic capacity, which provides potential targets for delivering designed molecules. The best route for targeting B- and/or T cell epitopes, however, is still the subject of intense investigation. Immature DC, which reside in various tissues, can be activated by pathogens, stress and inflammation or modified metabolic products, which induce mobilization of cells to draining lymph nodes where they act as highly potent professional antigen presenting cells. This is brought about by the ability to present their accumulated intracellular content for both CD4+ helper (Th) and CD8+ cytotoxic/cytolytic T lymphocytes (Tc/CTL). Engulfed proteins are processed intracellularly and their peptide fragments are transported to the cell surface in the context of major histocompatibility complex encoded class I and II molecules for presentation to Th cells and CTLs, respectively. The T cell priming capacity of DC, however, depends not only on antigen presentation but also on other features of DC. Human monocyte-derived DC provide an excellent tool to study the internalizing, antigen-presenting and T cell-activating functions of DC at their immature and activated differentiation states. These biological activities of DC, however, are highly dependent on their migratory potential from the peripheral non-lymphoid tissues to the lymph nodes, on the expression of adhesion molecules, which support the interaction of DC with T lymphocytes, and the cytokines secreted by DC, which polarize immune responses to Th1-mediated cellular or Th2-mediated antibody responses. These results altogether demonstrate that monocyte-derived DC are useful candidates for in vitro or in vivo targeting of antigens to induce efficient adaptive immune responses against pathogens and also against tumors.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Journal of Molecular Recognition. - 16 : 5 (2003), p. 299-317. -
További szerzők:	Réthi Bence (1973-) (biológus, immunológus) Hajas György (1970-) (biológus) Rajnavölgyi Éva (1950-) (immunológus)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM003461
Első szerző:	Kaczur Viktória
Cím:	Cleavage of the human thyrotropin receptor by ADAM10 is regulated by thyrotropin / Viktoria Kaczur, Laszló G. Puskas, Zsuzsanna U. Nagy, Nabil Miled, Ahmed Rebai, Ferenc Juhasz, Zoltan Kupihar, Agnes Zvara, Laszlo Hackler Jr., Nadir R. Farid
Dátum:	2007
Megjegyzések:	The thyrotropin receptor (TSHR) has a unique 50 residue (317-366) ectodomain insertion that sets it apart from other glycoprotein hormone receptors (GPHRs). Other ancient members of the leucine-rich repeat G protein-coupled receptor (GPCR) (LGR) family do exhibit ectodomain insertions of variable lengths and sequences. The TSHR-specific insert is digested, apparently spontaneously, to release the ectodomain (A-subunit) leaving the balance of the ectodomain attached to the serpentine (B-subunit). Despite concerted efforts for the last 12 years by many laboratories, the enzyme involved in TSHR cleavage has not been identified and a physiologic role for this process remains unclear. Several lines of evidence had suggested that the TSHR protease is likely a member of the a disintegrin and metalloprotease (ADAM) family of metalloproteases. We show here that the expression of ADAM10 was specific to the thyroid by specially designed DNA microarrays. We also show that TSH increases TSHR cleavage in a dose-dependent manner. To prove that ADAM10 is indeed the TSHR cleavage enzyme, we investigated the effect of TSH-induced cleavage by a peptide based on a motif (TSHR residues 334-349), shared with known ADAM10 substrates. TSH increased dose dependently TSHR ectodomain cleavage in the presence of wild-type peptide but not a scrambled control peptide. Interestingly, TSH increased the abundance of non-cleaved single chain receptor, as well higher molecular forms of the A-subunit, despite their enhancement of the appearance of the fully digested A-subunit. This TSH-related increase in TSHR digested forms was further increased by wild-type peptide. We have identified for the first time ADAM10 as the TSHR cleavage enzyme and shown that TSH regulates its activation.
Tárgyszavak:	Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban thyrotropin receptor, 50 residue insertion, A-subunit, DNA microarray, cleavage enzyme, ADAM10, TSHR substrate peptide
Megjelenés:	Journal of Molecular Recognition. - 20 : 5 (2007), p. 392-404. -
További szerzők:	Puskás László G. Nagy Zsuzsanna U. Miled, Nabil Rebai, Ahmed Kupihar Zoltán Zvara Ágnes Hackler László Jr. Farid, Nadir R. Juhász Ferenc (1952-) (sebész)
Internet cím:	elektronikus változat DOI
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