[Implication of different expression of IL-2 mRNA and IL-10 mRNA in CD4(+)CD25(+)T cell induced immune tolerance of liver transplantation in rat].
OBJECTIVE
To investigate the expression of tolerance-associated interleukin (IL)-2 mRNA and IL-10 mRNA in rats after allogeneic liver transplantation.


METHODS
The experimental rats were randomly divided into 3 groups: acute rejection model group (group I), CD4(+)CD25(+)T cell treatment group (group II), donors of the two groups were Wistar while recipients were Sprague-Dawley (SD) rats, and group III as control group, both donors and recipients of this group were SD rats, with 12 rats in each group. Splenic lymphocyte of donor in group II were injected through vena dorsalis penis 7 days before liver transplantation; equal volume normal saline (NS) were injected in rats of group I and III. The contents of IL-2 mRNA and IL-10 mRNA in the liver tissue were determined by reverse transcription-polymerase chain reaction (RT-PCR), and the number of lymphocytes in the donor liver was quantified with flow cytometry 7 days after transplantation. Meanwhile the pathologic change in the donor tissue were observed, and the recipients' life span was recorded.


RESULTS
IL-2 mRNA was expressed strongly in the liver of group I, but it was expressed weakly in group II, and no expression was detected in the liver of group III. IL-10 mRNA was expressed only in group II, and the level was high. The rats in group II and III survived over 30 days, but rats in group I had a shorter life (8-11 days, both P<0.01). There was heavy lymphocytic infiltration in the liver of group I,and was much higher than that of the other groups [group I:(14.31+/-3.41)x10(6)/g, group II: (5.04+/-1.13) x10(6)/g, group III: (1.55+/-0.40) x10(6)/g, all P<0.01], and pathology showed moderate rejection. Rats in group II had milder lymphocytic infiltration, and pathology showed no signs of rejection or uncertain rejection, and the ratio of CD4(+) T cell and CD4(+)CD25(+) were higher than those of group I [(43.31+/-8.07)% vs. (33.65+/-7.25)% and (11.39+/-1.92)% vs. (3.05+/-0.62)%] and group III [(43.31+/-8.07)% vs. (31.18+/-6.25)% and (11.39+/-1.92)% vs. (3.37+/-0.72)%, P<0.05 or P<0.01]. In group III no lymphocytic infiltration was found, and pathology showed no sign of rejection.


CONCLUSIONS
IL-2 may participate in the immune rejection in allogeneic liver transplantation, but IL-10 plays an important role in CD4(+)CD25(+) T cell inducing immune tolerance of allogeneic liver transplantation in the rats.
Shi
Liu-Bin
LB
Department of Hepatic Surgery, Huashan Hospital Affiliated to Fudan University, Shanghai 200040, China.
Zhang
Hong-Wei
HW
Cui
Yi-Yao
YY
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D007108:Immune Tolerance / Q000276:immunology; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism*; D007376:Interleukin-2 / Q000235:genetics / Q000378:metabolism*; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D016031:Liver Transplantation / Q000276:immunology*; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D014184:Transplantation, Homologous / Q000276:immunology
D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D012333:RNA, Messenger; D016753:Interleukin-10