Naslov
Hepatic T cell response in MCMV infected C57bl/6 mice after NKT cell activation

Autori
Hlača Caput, Tamara ; Trobonjača, Zlatko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
16th European Congress of Immunology, Book of abstracts / - Pariz : European Federation of Immunological Societies, 2006, 268-268

Skup
1st Joint Meeting of European National Societies of Immunology

Mjesto i datum
Pariz, Francuska, 06.09.2006. - 09.09.2006

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
NKT cells; murine cytomegalovirus; liver immunity; alpha-galactosylceramide

Sažetak
There are few cell populations prominent in the liver such as NK and NKT cells, APCs as well as lymphoid cell populations. Since the large amounts of data indicate that the hepatic T cell populations are responsible for effective viral clearance, we investigated activation of antiviral response after NKT cell stimulation by injection of the low dose alpha-galactosylceramide (alpha-GalCer). We injected alpha-GalCer every third day into the C57Bl/6 mice infected with murine cytomegalovirus (MCMV) during 15 days of disease course, always a day before mice were sacrificed. In another experimental setup we injected alpha-GalCer once into the infected mice day before they were sacrificed (7. or 10. or 14. day p.i.). We followed percentage of hepatic T cell subpopulations, NK and NKT cells as well as their activation status by CD69, CD45RB and CD44 staining. Virus titer was followed by PFU method. MCMV infection induced accumulation of CD3+NK1.1- cells in the liver, especially CD8+ CTLs 7. day p.i. alpha-GalCer slower the accumulation of the cells and move the peak of CTL hepatic infiltration to the later phase of disease course. alpha-GalCer injection induced activation of NK and NKT cells. To the contrary, MCMV infection decreased the percentage of CD69+ on both NKT and NK cells, 7-12 days p.i. while T cell subsets were activated. We found higher virus titer after multiple alpha-Gal/Cer injection 7-15 days p.i. T cell activation is determined by restimulation of isolated hepatic mononuclear cells by PMA and ionomycine followed by IFNgamma intracellular staining. Single dose as well as successive injecting of alpha-GalCer induced activation of all investigated cell subsets. The highest percentage of IFNgamma positive cells was found 7 days p.i. in CD8+ and CD4+ cells in MCMV infected mice. Injection of alpha-GalCer reduced the number of activated (IFNgamma+) cell subsets. During the later phase (14. days p.i.) percentage of activated cells in MCMV infected mice was normalised, and only alpha-GalCer injection induced IFNgamma production in T cell subsets. Those results are expected to contribute understanding of the role of innate immune cells activation in the maintenance of the specific immune response in the liver.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

POVEZANOST RADA