http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Thu, 23 May 2013 05:45:57 GMT 2013-05-23T05:45:57Z http://hdl.handle.net/2067/1681 Title: Evolution of cell-mediated immune defences: cloning and structural characterisation of the T cell receptor beta chain from the icefish Chionodraco hamatus (Perciformes: Channichthyidae) Authors: Buonocore, Francesco; Randelli, Elisa; Viviana, Scala; Belardinelli, Maria Cristina; Casani, Daniela; Facchiano, Angelo M.; Costantini, Susan; Scapigliati, Giuseppe Abstract: Studies on the immune defence system of Antarctic fishes are of interest to investigate the presence of evolutionary adaptations to low temperature seawater. In the present paper, primers designed to conserved regions of TR , the antigen receptor expressed by T lymphocytes and mediator of main adaptive immune responses, were used for the homology cloning of the icefish Chionodraco hamatus TR  chain cDNA. The full length cDNA consists of 1219 nucleotides that translates in a single reading frame to give a predicted 304-amino acid molecule. The sequence shows highest nucleotide and amino acid identity with the sea bream (Sparus aurata) TR  . A multiple alignment with other known TR  molecules evidenced the presence of conserved amino acid residues involved in structural and functional domains within most teleost species. Real-time PCR analysis was used to investigate TR  basal expression, that resulted maximal in the thymus, followed by gills and spleen. Finally, the 3D structure of the icefish TR  was predicted by homology modelling and compared to the closest homologous Sparus aurata, a fish Teleost living in more temperate environmental conditions. The comparison of these two models suggests that the icefish TR  may be more flexible, as a consequence of a less compact structure and a lower number of H-bonds. Description: L'articolo è disponibile sul sito dell'editore http://www.tandfonline.com/ Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1681 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1426 Title: Do all stoneflies nymphs have respiratory proteins? Further data on the presence of hemocyanin in the larval stages of plecoptera species Authors: Amore, Valentina; Belardinelli, Maria Cristina; Guerra, Laura; Buonocore, Francesco; Fausto, Anna Maria; Fochetti, Romolo Description: L'articolo è disponibile sul sito dell'editore http://onlinelibrary.wiley.com Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1426 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1561 Title: The thyroid disruptor 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (DDT) prevents internalization of the TSH receptor Authors: Picchietti, Simona; Belardinelli, Maria Cristina; Taddei, Anna Rita; Fausto, Anna Maria; Pellegrino, M.; Rossi, M.; Maggio, Roberto; Giorgi, Franco Abstract: The thyroid-stimulating hormone (TSH) receptor (TSHr) was made specifically fluorescent by insertion of a tetracysteine motif (TSHr-FlAsH) into the C-terminal end and transiently transfected into COS-7 and HeLa cells. The observation that TSH administration caused the intracellular level of cAMP to increase in both TSHr-FlAsH-transfected cell types indicated that the FlAsH binding motif did not alter normal TSHr functioning. When transfected into HeLa cells and stimulated with TSH, the TSHr-FlAsH receptor exhibited a pronounced perinuclear labelling pattern, whereas labelling remained on the cell surface following pre-incubation with 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT). Chinese hamster ovary (CHO)-TSHr cells probed with anti-TSHr antibodies were fluorescent mainly in the proximity of the plasma membrane, with fluorescence being primarily restricted to a juxta-nuclear position when exposed to 10 mU/ml TSH for 1 or 5 min. However, in the presence of DDT, the anti-TSHr fluorescence maintained a peripheral location along the cell plasma membrane, even if CHO-TSHr cells were stimulated with TSH for 1 and 5 min. To verify that DDT acted specifically on the TSHr, CHO cells transfected with the A2a receptor were used as controls. Following a 1-min stimulation with 5’-(N-ethyl-carboxamido)-adenosine, A2a receptors were gradually internalized regardless of the presence of DDT in the culture medium. Finally, immunoelectron microscopy of CHO-TSHr cells showed that a 1-min exposure to TSH sufficed to displace anti-TSHr antibodies tagged with 10- nm gold particles into coated pits and vesicles but that their superficial location was retained along the plasma membrane in the presence of DDT. Description: L'articolo è disponibile sul sito dell'editore http://www.springerlink.com/ Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1561 2008-12-31T23:00:00Z http://hdl.handle.net/2067/2183 Title: Intestinal T cells of Dicentrarchus labrax (L.): gene expression and functional studies Authors: Picchietti, Simona; Guerra, Laura; Bertoni, Fabrizio; Randelli, Elisa; Belardinelli, Maria Cristina; Buonocore, Francesco; Rombout, Jan; Scapigliati, Giuseppe; Abelli, Luigi Abstract: Cellular and molecular data have evidenced a gut-associated lymphoid tissue in a variety of teleost species, abundantly containing T cells, whose origin, selection and functions are still unclear. This study reports CD4, CD8-α, MHCI-α, MHCII-β, rag-1 and TCR-β gene transcription along the intestine (anterior, middle and posterior segments) and in the thymus of one year-old Dicentrarchus labrax (L.). Real-time PCR findings depicted a main role of the thymus in T cell development, but also rag-1 and CD8-α transcripts are detected in the intestine, having significant expression in the posterior segment. In the whole intestine TCR-β and CD8-α exceeded CD4 transcripts. RNA ISH confirmed these data and detailed that mucosal CD8-α+ cells were especially numerous in the epithelium and in aggregates in the lamina propria. Regional differences in T cell-specific gene expressions are first described in the intestine of a bony fish. High non-specific cytotoxic activity against xenogeneic and allogeneic cells was found in lymphocytes purified from the intestinal mucosa, providing further insight into their local defence roles. Description: L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com/ Fri, 31 Dec 2010 23:00:00 GMT http://hdl.handle.net/2067/2183 2010-12-31T23:00:00Z