ABSTRACT
Objective To explore the relationship between cellular rejection and the development of allo-or xenografted primordia from different gestational ages .Methods Whole rat metanephroi from embryonic day E14～ E19 were transplanted into omenta of outbred (SD → SD ,6 groups ,n≥10 each ;E15-E17SDCsA ,3 groups ,n=15 each) ,syngeneic (Lewis→Lewis ,5 groups ,n=8 each) ,allogeneic (Lewis→BN ,E15BN n= 6 each E15BNCsA n= 10 each ,E16BNCsA n= 10 each) rats and xenogeneic (Lewis→C57groups ,E15C57 n=10 each ,E15C57CsA ,n=8 each ;Lewis→Balb/c nude mice ,3 groups ,n=10 each) recipients .Histopathology ,Banff's grading and electron microscopy (EM ) were utilized for assessing the graft development .Similarly ,biochemical indicators and creatinine clearances were measured .Results At 4 weeks post-transplantation , in SD → SD groups ,E14-E17SD metanephroi developed with Banff ' s rejections . E14/E15SD was significantly lighter than E16/E17SD ( P< 0 .01 );E18/E19SD barely developed . After cyclosporine A (CsA , 8 mg·kg -1·d-1 )dosing ,Banff's rejection of E15-E17SDCsA group lessened significantly .In Lewis→BN ,E15BN metanephroi were completely rejected .After dosing CsA (12 mg·kg -1·d-1 ) ,E15BNCsA and E16BNCsA Banff ' s rejections became alleviated . Upon a discontinuation of CsA , both metanephroi were rejected . In Lewis → Lewis , E15 ～ E17Lewis metanephroi developed well . No significant difference existed in Banff's classification (P>0 .05) .E14Lewis and E18Lewis rats had significantly poorly differentiated metanephroi than those in E16 Lewis group .In Lewis→C57BL/6 , E15 metanephroi were rejected at Day 14 post-transplantation (n= 10) and no improvement was evident after CsA dosing (15 mg·kg -1·d-1 ,n=8) .In Lewis→Balb/c nude mice ,all E15～E17Balb/c metanephroi developed well .Both light microscopy and EM examination showed normal nephrons and collecting ducts and wet weight ,creatinine or urea nitrogen of effusion showed no significant difference (P>0 .05) .E15Lewis and E16Lewis had significantly different values of wet weight and creatinine clearances from those of E15SDCsA and E16SDCsA .E15SDCsA had the greatest wet weight and the lowest creatinine clearance rate (P< 0 .01) .Conclusions After controlling rejection during allo-and xenotransplantations ,E15 ,E16 and E17 rat metanephros have similar development characteristics . And cellular immunogenic factors still remain the major barriers to their developments .
ABSTRACT
ObjectiveTo investigate whether the cellular immune function of athymia nude mice can be reestablished and whether the recipients' specific immune tolerance can be induced by the combined xenotransplantation of embryonic thymus and metanephros anlagen from rats to athymia nude mice.Methods Male and female rats were mated overnight.The presence of vaginal plaques was marked as the embryonic day 0(E0).The whole embryos from Lewis rats on embryonic day 15(E15) were taken for the present experiment.The Lewis E15 metanephros and thymus anlagen were taken out from the embryos and immediately preserved in normal saline at 4℃,and then were implanted into the omentum and renal capsule of nude mice.10 weeks post-implantation,the peritoneotomy was carried out on some recipients,metanephros and thymus transplants were removed for histopathological examination.The concentrations of urea nitrogen and creatinine in cyst fluid from the metanephros transplants were measured.The survival time of the recipients was observed after nephrectomy.The blood of the recipients was obtained to detect the re-establishment of T lymphocyte with flow cytometry(FCM).The lymphocyte suspension extracted from recipients were mixed respectively with the spleen cells suspension of Lewis rats,BN rats or C57BL/6 mice to perform mixed lymphocyte reaction(MLR) test.The skins of Lewis rats,BN rats,C57BL/6 and nude mice were transplanted in the chest-back of the recipients to observe the reject reaction.Results10 weeks post-implantation,both E15 metanephros and thymus transplants were enlarged,and showed well-developed structure under optical microscope and electronic microscope.Metanephros displayed partial excreting function.The concentrations of urea nitrogen and creatinine in cyst fluid from the metanephros transplants were close to the concentrations in the bladder urine.The combined transplant recipients survived longer than the others after nephrectomy(P ＜0.05).The re-establishment of T lymphocyte from the blood of recipients was certified by FCM.MLR indicated that the lymphocyte of the combined transplant recipients had normal reaction to the spleen cells of the BN rats and C57BL/6 mice,but had under-reaction to the donor Lewis's( P＜0.01 ).Survival time of the skin from donor Lewis is longer than that of the BN rats' and the C 5 7 BL/6 mice' s ( P ＜ 0.01 ).Conclusion E15 Lewis metanephros and thymus anlagen heterografted into the athymia nude mice will grow and function well.The nude mice with combined transplantation of E15 Lewis thymus and metanephros anlagen can reestablish immunologic function and may induce tolerance to the metanephros and skin graft from donor Lewis