Experimental Research On Immunologic Tolerance Induced By Immature Dendritic Cells In Rat Transplantation

[Objective] To study the effects of various doses and administration schemes of immature dendritic cells(imDCs) on immunologic tolerance in rat transplantation and investigate the mechanism of the immunologic tolerance induced by imDCs.[Methods] Bone marrow cells of Wistar rats were cultured in Roswell Park Memorial Institute 1640(RPMI1640) medium with low dose of recombinated rat GM-CSF(1.5ng·ml^-1) and IL-4(4 ng·ml^-1) and a great quantity of imDCs were harvested.SD rats were divided in four guoups: 1.control group that normal sodium was injected via vena caudalis the day before the operations;2.Low dose group that 2×10⁶ imDCs were injected via vena caudalis the day before the operations;3.High dose group that 2×10⁷ imDCs were injected via vena caudalis the day before the operations;4.Four times injections group that imDCs were injected at various times(days-1,0,1,5).SD rats served as heart donors and Wister rats served as allograft recipients.Graft survival was monitored daily by cervical palpation.MLR,heart pathology and serum levels of IL-2,IL-4,IL-10,INF-r were detected after operations.[Results] 1.The separated cells were spherical,small and floating in the culture fluid.On the third day,part cell grew adhering the wall and the cell body increased.On the fifth day,sentus-shape cells appeared but the sentus were short and had less branchs.On the seventh day,the sentus were still not obvious.The expressions of CD80,CD86 were low analyzed by FCM.2. We have achieved 52 cases of heterotopic heart transplantation in rat.The time of getting out the hearts was 400.5±32.7 seconds and the time of vascular anastomosis was 5.4±115.9 seconds.Main survival time of the control group was 6.8±1.0 days.The achievement ratio is 83.6%.Complications were anastomotic orifices hemorrhage(5 cases),thrombosis(3 cases),respiration ceases(2 cases),long donor ischemic time(1 case),infection(4 cases)and death with unclear causes(2 cases).3.The MST of high dose group and four times injection group was longer than other groups.The MST of low dose group was different from the control group.The MST of high dose group was not different from four times injection group. 4. As SD rat spleen cells being the stimulating cells, there were significant difference of...