Projekti / Programi
Proučevanje celičnega imunskega odziva na izbrane peptide prionskega proteina
| Koda |
Veda |
Področje |
Podpodročje |
| 3.01.00 |
Medicina |
Mikrobiologija in imunologija |
|
| Koda |
Veda |
Področje |
| B000 |
Biomedicinske vede |
|
| B500 |
Biomedicinske vede |
Imunologija, serologija, transplantacija |
Prionske bolezni, peptidi, in vitro testi, limfociti T, aktivacija in proliferacija, aktivacija citokinov, izražanje specifičnih celičnih markerjev.
Raziskovalci (1)
| št. |
Evidenčna št. |
Ime in priimek |
Razisk. področje |
Vloga |
Obdobje |
Štev. publikacijŠtev. publikacij |
| 1. |
28281 |
dr. Mascia Ghielmetti |
Mikrobiologija in imunologija |
Vodja |
2007 - 2008 |
6 |
Organizacije (1)
Povzetek
Prion diseases, including Bovine Spongiform Encephalopathy (BSE), Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker disease (GSS) and Fatal Familial Insomnia (FFI) are fatal and neurodegenerative infectious disorders in animals and humans, respectively. Normal cellular prion protein (PrPC) is expressed on the surface of various cell types, but most abundantly on neurons. Posttranslational conversion of PrPC into a pathological scrapie prion protein (PrPSc) leads to extensive neuronal cell loss by a yet unclear mechanism. Irreversible brain damage is reflected as loss of coordination and dementia.
Since prion diseases are transmissible within and even between species, the need for pre- and post-exposure treatment is evident. In fact, BSE has been transmitted from cattle to humans to cause a new variant of Creutzfeldt-Jakob disease (vCJD). In recent years, transmission by blood transfusion was reported.
So far, prion diseases are best investigated in the mouse model. In prion-infected mice, the abnormal proteins can be detected on cells in the spleen and lymph nodes before they reach the brain. Surprisingly, PrPSc infection of the host does not induce an antibody (Ab) response, indicating immune tolerance due to the similarity with the normal PrPC. Since the pathologic effect is limited to the brain, the effective treatment in early prion infection is needed. To overcome a long incubation period, in vitro assays are required to investigate the effect of PrP on cells of the human immune system.
In the recent years, the research group Biomedicine in the Centre for the Production of Diagnostic Reagents and Research, Blood Transfusion Center of Slovenia, Ljubljana, was able to improve the knowledge and techniques in the basic prion research, having also applicative value. In particular, a sensitive assay was developed to detect the pathological PrPSc isoform by generating a monoclonal Ab, specific for human prion protein that discriminates between CJD – affected and normal brain tissue1,2,3. Furthermore, the laboratory developed a fast technology, based on the Real Time PCR, to analyze genetic risk factors, associated with CJD in Slovenians4.
To continue prion research, the main goal of the present project is to assess the capacity of different synthetic peptides, based on the human PrP sequence, which were already used to stimulate B lymphocytes in vivo1,2, to activate T lymphocytes in vitro. The methods will be established first in in vitro assays on isolated mouse and later also on human T lymphocytes. In particular, we will focus on T cell proliferation, cytokine production and specific cell marker expression. The results will provide the amino acid sequence required for lymphocyte activation. Since it is known that the pathogenic prion protein forms aggregates, we will investigate the activation capacity of different conformations, including dimers and polymers of the most effective peptide, P11,2,5. In a final step, we will establish a system to predict the stimulatory potency of prion peptides on human T cells in vitro.
Our investigations will support the generation of a specific prion treatment, particularly a vaccine formulation appropriate also for human use.
1Čurin Šerbec V, Bresjanac M, Popović M, Pretnar Hartman K, Galvani V, Rupreht R, Černilec M, Vranac T, Hafner I, Jerala R., J Biol Chem, 2004; 279: 3694-3698.
2Vranac T, Hartman KP, Popović M, Venturini A, Zerovnik E, Čurin Šerbec V. Peptides. 2006 Jul 19; [Epub ahead of print]
3 Čurin Šerbec, V. Antibodies capable to selectively detect prion PrPSc isoforms. EP 1158003, 2005.
4Galvani V., Rupreht RR, Čurin Šerbec V, Vidan-Jeras, B, Transfus Med, 2005; 15: 197-207.
5Poklar Ulrih N, Skrt M, VeraniČ P, Galvani V, Vranac T, Čurin Šerbec V, BBRC, 2006 ; 344 : 1320-1326.
Pomen za razvoj znanosti
Zaenkrat učinkovito zdravljenje prionskih bolezni ni možno. Osredotočili smo se na celice imunskega sistema. Pri tem je ključen problem podobnost med molekulama PrPC in PrPSc. V preteklih letih je naša skupina proučevala protitelesni imunski odziv na izbrane peptide iz zaporedja humanega prionskega proteina.
Da bi bolje razumeli problem tolerance in imunogenosti prionskih peptidov, smo raziskave razširili na celični imunski odziv. Zato smo postavili dva modela, humanega in mišjega, ki sta zelo uporabna za proučevanje avtoimunosti določenih peptidov.
S pomočjo humanega modela smo izboljšali mišji model. Ker smo iz krvi zdravih krvodjalcev pridobili dovolj celic, da smo testirali različne pogoje, je bilo možno prenesti rezultate na mišji model. S tem smo zmanjšali število poskusov na živalih. V mišjem modelu je možno testirati celotni imunski odziv na peptid, se pravi T-celični ter pridobitev specifičnih protiteles. S tem lahko preučujemo celotni imunski odgovor na prionski peptid.
Rezultati so in še bodo pomembni za poznavanje imunosti pri prionskih boleznih ter za morebitno načrtovanje vakcin.
Pomen za razvoj Slovenije
V preteklih letih je raziskovalna skupina Biomedicina uspešno pripomogla k razvoju znanja na področju prionskih bolezni. S tem projektom smo nadaljevali in celo razširili naše znanje in tehnike v imunologiji in s tem tudi na področju prionov. Rezultati nam bodo pomagali pri izvajanju različnih projektov in pri pridobivanju novih idej.
Nadaljne raziskave lahko vodijo do razvoja specifičnega zdravljenja prionskih bolezni.
Najpomembnejši znanstveni rezultati
Zaključno poročilo,
celotno poročilo na dLib.si
Najpomembnejši družbeno–ekonomsko in kulturno relevantni rezultati
celotno poročilo na dLib.si
