Naslov
On the role of NK cells in liver regeneration

Autori
Radošević-Stašić, Biserka ; Trobonjača, Zlatko ; Ravlić-Gulan, Jagoda ; Ćuk, Mira ; Mrakovčić-Šutić, Ines ; Rukavina, Daniel

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

Izvornik
Periodicum biologorum 100 (1998), suppl. 3 / Vitale, Branko - Zagreb : Hrvatsko prirodoslovno društvo, 1998, 32-32

Skup
Fourth international meeting "Mechanisms in local immunity" and Fourth meeting of Alps Adria society for immunology of reproduction

Mjesto i datum
Opatija, Hrvatska, 16.09.1998. - 19.09.1998

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
NK and NK1.T cells; liver regeneration

Sažetak
Liver regeneration that follows after partial hepatectomy (pHx) is well defined process which involves the concerted action of extra and intrahepatic factors resulting in induction of cell replication and its inhibition at time when the entire liver mass is restored. Since it has been implicated that partial resection of parenchymal organs may lead to the breakdown of previously maintained tolerance to self antigens and activation of pre-immune or natural immune repertoire, in this study we attempted to analyze the role of major histocompatibility antigens (MHC) class I-encoded molecules and natural killer (NK) cells is these events. For this purpose compensatory liver growth was estimated: 1) in MHC class I deficient mice (b2-m -/-), which do not express correctly folded MHC class I trimolecular complexes and are devoid of CD8+ T cells, 2) in mice in vivo depleted of NK1.1. cells and 3) in perforin deficient mice, which have normal numbers of CD8+ and NK+ cells, but which are unable to lyse the transformed targets. Intensity of liver growth after 1/3 pHx was estimated by cell cycle analysis. Simultaneously, the phenotype of intrahepatic and thymic lymphoid cells were determined, using the cytofluorometric screening. The data showed that early phase of liver regeneration is characterized by an early peak of intrahepatic NK1.1.+ and CD5+ cells, which disappeared on the second p.o.day. In mice with intact function of MHC molecules, the elimination of NK1.1. cells augmented the S phase of hepatocytes (at 1st and 2nd day after pHx), while in the MHC deficient mice, the early S phase was initially reduced (at 1st day) and then markedly increased (at 2nd and 7th day), pointing to the possibility that MHC molecules on target cell may prevent the NK cell-mediated cytotoxicity during the liver growth. Furthermore, the data showed that MHC class I expression was necessary for the decline of CD4+CD8+ T cells in thymus, suggesting their role in the process of negative selection of self-reactive lymphocytes activated by pHx.

Izvorni jezik
Engleski

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