Naslov
The role of regulatory t cells (tregs) in pregnancy

Autori
Mrakovčić-Šutić, Ines, ; Jakovac, Hrvoje, ; Grebić, Damir

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Abstract Book of the 6th European Congress of Reproductive Immunology / - , 2008

Skup
European Congress of Reproductive Immunology (6 ; 2008)

Mjesto i datum
Moskva, Ruska Federacija, 30.06.2008. - 04.07.2008

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
NKT cells; pregnancy; Tregs; syngeneic murine pregnancy

Sažetak
The immune system distinguishes between multifactor stimuli whom allow to react or to reject the immunological response. «Fetal allograft» is commonly used as a description of fetal immunological status during pregnancy. Maternal immunological acceptance of fetal antigens can be explained as a status of recipient's tolerance to an engrafted organ, whereas immunopathological recognition of fetal antigens which occurs in recurrent abortion and pre-eclampsia can be described as a graft rejection-like alloimmune reaction. The elevated number of Tregs during pregnancy is reported in murine pregnancy, as well as in humans, while decreased number was seen in patients with spontaneous abortion. Improving the thesis of suppressor function of these cells, it is shown that Tregs from normal pregnant mice are capable to prevent fetal rejection in vivo. It is obviously that Tregs participate in mediating maternal tolerance to the fetus. A specific function in these events seems to have also extrathymically generated NK and NKT cells, which show synchronous expansion in the liver and in the pregnant uterus. Although it is repeatedly demonstrated that invariant natural killer T (iNKT) cells perform an important function at the maternal-fetal interface, where during the pregnancy on villous and extravillous trophoblasts is expressed CD1d, the role of the hepatic NKT cells, during the pregnancy is still not well understood. Experiments were done on pregnant C57/BL6 mice, and phenotype of lymphoid cells were detected on the 16th day of pregnancy in the liver, thymus and spleen by FACSCalibur analysis. Simultaneously the cytotoxicity of intrahepatic and splenic mononuclear lymphatic cells was tested against syngeneic thymocytes and NK-sensitive targets(YAC-1). The findings were compared with data obtained in non-pregnant mice, living in the normal laboratory conditions. The data revealed that pregnancy moderately upregulates the Tregs (CD4+ CD25+ FoxP3+) expression in the liver mononuclear lymphatic cells. Simultaneously, in the liver accumulated NKT cells and NK cells and hepatic MNLC became more cytotoxic against the syngeneic thymocytes (p<0, 01), and less cytotoxic against the YAC-1 target. It correlates with the increased number of hepatic Tregs in pregnant mice. The data suggest that pregnancy upregulate traffics of Tregs and NKT cells in the liver and in the lymphatic organs, activating NKT and other cells that might mediate the cytotoxicity against altered self.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

POVEZANOST RADA