首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
We investigated the effect of donor-specific transfusion given 24 hours pretransplant, a short course of low-dose cyclosporine, and dietary enrichment with the prostaglandin precursor linoleic acid (LA) to see which of the modalities could act synergistically on cardiac allograft survival in a stringent animal model. ACI male rats (RT1a) were used as blood and heart donors, and Lewis male rats (RT1l) were used as recipients. DST alone (1 ml) given 24 hr pretransplant or LA alone started 24 hr pretransplant and given daily p.o. until rejection prolonged cardiac allograft survival slightly but significantly, from 6 to 8 days. CsA alone started at the time of transplant at a dose of 5 mg/kg/day s.c. and given daily for 14 days prolonged cardiac survival to 11.8 days. However, when CsA was started 24 hr pretransplant and continued for two weeks, there was a significantly prolonged allograft survival to 55 days. CsA given together with DST 24 hr pretransplant and continued for two weeks posttransplant significantly prolonged cardiac allograft survival to 80 days and resulted in permanent tolerance in some animals. The addition of LA to a DST and CSA treatment regimen did not further improve allograft survival. CsA blood levels were determined in a separate group of Lewis rats. Three dosages of CsA were administered s.c. for 2 weeks: 2.5 mg/kg/day, 5 mg/kg/day, and 10 mg/kg/day. One injection of the three CsA doses did not achieve what are considered therapeutic levels in man. After 5 days, all three doses of CsA achieved significant blood levels. Significant blood levels were still present one week, but not 3 weeks after CsA was stopped. We conclude that DST given 24 hr before transplant and a 2-week course of low-dose CsA started one day pretransplant have strong synergism in inducing long-term graft survival in this rat model. Linoleic acid started 24 hr pretransplant, together with DST and CsA, did not contribute significantly to graft survival compared with the group given CsA and DST alone. Prolonged heart allograft survival was not due to persistently high CsA levels after the drug was discontinued.  相似文献   

2.
目的探讨FK506和供体特异性输血在大鼠异位心脏移植中的作用。方法利用大鼠异位心脏移植模型以了解在移植当天或移植术后第4日进行供者特异性输注(DST)的基础上,应用FK506能否延长移植物的存活。结果在移植当天行DST或单独用FK5061mg/kg连续10天,可将移植心中位存活时间从对照组的5天分别有效延长至7天和11天,而FK506与DST联合应用时并不产生增强效应。结论FK506和DST单独应用时虽均能延长大鼠同种移植心存活,但是它们没有协同作用。  相似文献   

3.
A new protocol of donor-specific blood transfusion under cyclosporine coverage was developed and examined for immunologic consequences and clinical efficacy in recipients of one- or zero-HLA-haplotype-matched renal allografts. Between 1985 and 1989, 75 recipients were transfused with 100 ml of stored whole blood at 1, 8, and 15 days of its storage from either one-HLA-haplotype-matched related donors (n = 65, 33 from their parents, 30 from siblings, and 2 from offspring) or from zero-HLA-haplotype-matched donors (n = 10, 7 from spouses and 3 from siblings). During DST, all recipients received cyclosporine, 6 mg/kg/day, starting a day before and finishing a week after DST (23 days). Recipients were monitored by donor-specific mixed lymphocyte culture responses before and after DST, and serially for antibodies by fluorescence activated cell sorter analysis and by standard complement-dependent lymphocytotoxicity assay. Following DST with CsA, only 3 of 75 patients (4%) were sensitized against the blood donor. This rate is considerably lower, albeit statistically not significantly, compared with the 10% rate found in 30 recipients who had received DST without CsA in our previous study. Repeat MLC studied one to two months after DST (the day before transplant) were significantly increased compared with pre-DST (stimulation index: mean +/- SEM; 10.3 +/- 1.4 to 15.8 +/- 2.8, P = 0.004, and relative response: 40.9 +/- 5.1% to 49.8 +/- 5.5%, P = 0.003). Since the stimulation index with controls did not change after DST (23.4 +/- 2.9 to 26.2 +/- 3.3), enhanced MLC responses appear to be donor-specific. The changes in MLC responses did not correlate with the number of blood transfusion received prior to DST, the number of rejection episodes, or graft outcome. Fifty-seven recipients underwent a kidney transplant from their one-HLA-haplotype-matched blood donors within two to three months after DST. All 10 recipients of zero-haplotype-matched donors were also successfully transplanted from their respective blood donors. The graft survival rates were at least 90% at two years in both groups. In conclusion: (1) 100 ml of stored whole-blood DST, three times at weekly intervals with a short course of CsA is minimally sensitizing but effective in enhancing graft survival; (2) this protocol could be used in donor-recipient pairs who do not share a haplotype; and (3) DST with CsA elicits augmentation of donor-specific MLC responses.  相似文献   

4.
Pregraft transfusion combined with immunosuppression at the time of grafting improves the survival of clinical and experimental allografts. The mechanisms responsible for this effect were investigated in the murine model of cardiac transplantation, combining transfusions 7 to 30 days prior to transplantation with cyclosporine 100 mg/kg, 7 to 20 days pregraft or on days 0, 4, and 6 after grafting. Pregraft DST, third-party blood, and CsA all improved graft survival in the BALB/c-to-CBA donor-recipient combination. In animals treated with DST at 14 days pregrafting, 4/9 grafts survived for greater than 100 days. In those given C57BL/6 blood, or CsA on days 0, 4, 6 postgraft, 1/9 grafts survived for greater than 100 days. When 10(7) spleen cells from DST-treated CBA mice with long-surviving BALB/c heart grafts were transferred to naive CBA mice that then received a BALB/c heart 24 hr later, the transferred cells prolonged graft survival, with all grafts functioning at greater than 40 days, and 4/7 at greater than 100 days. Selective removal of T cells from the spleen cell population prior to transfer showed that L3T4+ T cells, but not Ly-2+ T cells, were required to maintain BALB/c allografts. Combining a short course of CsA with DST was more effective than either treatment alone. The most effective combined treatment was DST at day -14 with 100 mg/kg CsA given on days 0, 4, and 6 postgrafting (8/10 grafts survived greater than 100 days). This treatment also induced splenic suppressor T cells of the L3T4+ Ly-2- phenotype. These results clearly show that L3T4+ splenic T suppressor cells are induced by donor-specific blood transfusion with or without CsA treatment, and that these cells play a role in maintaining long-term tolerance to allografts in the mouse heart transplant model.  相似文献   

5.
The tolerogenic effects of immediate pretransplant donor-specific transfusion (DST) with cyclosporine (CsA) have been well described. The purpose of this study was to determine if these effects could be improved upon by the administration of post-transplant DSTs. When added to a 29-day course of CsA, a single DST given 24 hr pretransplant improved graft survival compared to CsA alone (84.9 +/- 12.3 vs 40.0 +/- 8.8 days; P less than 0.05). The administration of an additional DST on post-transplant Days 7, 14, and 21 further improved this survival to 152 +/- 28 days, with 45% of grafts surviving greater than 200 days, until sacrifice. The donor specificity of this effect was demonstrated by the increased survival of second ACI grafts transplanted into Lewis recipients with existing "tolerant" ACI allografts (long-term survivors, or LTS); third-party Buffalo rat hearts transplanted into LTS rats in a similar manner were rejected normally. Loss of graft antigenicity was not seen, as retransplanted ACI hearts obtained from LTS Lewis rats were rejected in a first-order manner. From this we conclude that (1) the addition of multiple post-transplant DSTs improve the enhancement seen with preoperative DST and CsA, (2) loss of graft antigenicity does not contribute to this improved enhancement, and (3) this effect appears to be donor antigen specific.  相似文献   

6.
In order to avoid cyclosporine (CsA) nephrotoxicity and rejection, especially during the early posttransplant periods, different immunosuppression regimens have been adopted. A prospective trial was conducted to evaluate the benefits of initially low CsA doses associated with antilymphoblast globulin and steroids in the first days after transplant, in comparison with higher doses of CsA and steroids. Between 1/86 and 1/88, two groups of first-cadaver renal transplant recipients were documented based on the immunosuppression regimen used. In group A (n = 50), oral CsA was started at 8 mg/kg/day and subsequent doses adjusted to maintain CsA whole-blood levels between 300 and 600 ng/ml. Horse ALG at 10 mg/kg was given the day after transplant and on alternate days to a maximum of 6 doses. After 3 doses, ALG was stopped if CsA blood levels were equal to or greater than 400 ng/ml. ALG dosage modifications were made in order to maintain peripheral CD3+ cells between 10 and 20%. Prednisone was given at 0.25 mg/kg/day. In group B (n = 50), oral CsA was started at 15 mg/kg/day. The CsA whole-blood levels were maintained between 300 and 800 ng/ml. Prednisone was administered at 0.5 mg/kg/day. The incidence of postransplant renal failure was the same in both groups (16%), but the duration of oliguria was lower in group A than in group B (3.3 +/- 2 vs. 16.2 +/- 10.7 days, P less than 0.05), as well as the incidence of acute rejection during the first 3 months (18% vs. 40%, P = 0.01. The cumulative doses of CsA and steroids were significantly lower in group A than in group B. Mean serum creatinine at 6 and 12 months remained similar in both groups. There was no difference between the 2 groups in the incidence of infection. There was no mortality in either group. The actuarial graft survival was significantly higher in group A than in group B at one (100% vs. 94%), two (97% vs. 87%), and three years (89% vs. 73%), respectively (P = 0.041). In summary, the triple regimen using simultaneously low-dose CsA, ALG, and steroids minimizes early graft dysfunction, provides efficient immunosuppression without severe infections, and gives good long-term patient and graft survival.  相似文献   

7.
We investigated the effect of pretransplant conditioning as a way to reduce the need for the aggressive immunosuppressive therapy reportedly required in small bowel (SB) allograft recipients. LEW rats were conditioned with (1) a donor-specific blood transfusion (DST) on day -8 and a concurrent 5-day course of CsA (10 mg/kg/day); (2) a nonspecific blood transfusion and CsA; (3) CsA alone. A 10-cm segment of the host native bowel was then replaced with an equivalent segment of SB obtained from ACI rats. Postoperative treatment consisted of CsA at 2.5 mg/kg/day for 30 days. Rats conditioned with a nonspecific transfusion and CsA or with CsA alone survived for 14.1 +/- 5.8 and 18.3 +/- 5.7 days, respectively. In contrast, rats conditioned with DST and CsA survived for 60.3 +/- 36.2 days (P less than 0.001 vs. both controls). Biopsies taken from long-term survivors showed a normal bowel architecture. The function of the allografts was studied in a group of animals totally deprived of their native bowel and transplanted with a 30-cm segment of ACI SB. CsA-DST-treated recipients survived an average of 90 +/- 43 days and grew at a rate comparable to isografted animals. Treated allograft recipients had maltose absorption indistinguishable from isografted controls at all times tested. In contrast, maltose absorption was severely impaired in recipients rejecting their grafts. This study demonstrates that long-term survival of SB allograft recipients can be achieved with good functional results with low doses of CsA in recipients conditioned with DST and CsA.  相似文献   

8.
We have previously demonstrated that pretreatment of ACI recipients with ultraviolet-irradiated donor-specific blood transfusion (UV-DST) leads to permanent cardiac allograft survival without further host immunosuppression (ACI rats are weak responders to Lewis lymphocytes in mixed-lymphocyte reaction). This study examines the effect of UV-DST and the timing of transfusions on ACI cardiac allograft survival in Lewis recipients with and without the addition of peritransplant cyclosporine (CsA) (20 mg/kg i.m.) given on days 0, +1, and +2 in relation to the time of transplantation. The mean survival time (MST) of ACI cardiac allografts in Lewis recipients was significantly increased to 33.6 +/- 5.7 days (P less than 0.001) by CsA treatment alone as compared to 6.5 +/- 0.5 days survival in control. When DST was given on day -3 combined with CsA, graft survival was increased to 42.0 +/- 9.3 days (P less than 0.01), as compared to 5.8 +/- 1.3 days when DST alone was used. When DST was irradiated with ultraviolet B (UV-DST) and administered on day -3 combined with peritransplant CsA, the MST was increased to 68.83 +/- 16.1 days as compared to an MST of 10.0 +/- 1.0 days in controls treated with UV-DST alone. When UV-DST was given on day -7 and combined with peritransplant CsA immunosuppression, the results were similar. However, when UV-DST was peritransplant CsA course, 4 of 6 recipients maintained their ACI heart allografts indefinitely (greater than 300 days) in contrast to the effect of UV-DST alone (MST of 13.5 days). Third-party (W/F) UV-irradiated blood transfusions were ineffective in prolonging ACI cardiac allografts in Lewis rats, regardless of whether the transfusions were given alone or in combination with peritransplant immunosuppression with CsA. In conclusion, these results demonstrate that UV-DST combined with a brief peritransplant immunosuppression with CsA induces prolonged heart allograft survival in a histoincompatible, strong responder host, and that such effect is donor specific. The use of UV-DST combined with peritransplant CsA immunosuppression offers a promising approach to achieving organ transplant unresponsiveness, and decreased sensitization to the donor blood elements, which eventually may have important clinical implications.  相似文献   

9.
BACKGROUND: The addition of induction therapy with antilymphocytic antibodies to cyclosporine (CsA) based immunosuppression, has reduced acute rejection incidence and improved short-term survivals, but has not had well-established effects on long-term renal transplant survival. PATIENTS: We analyzed the long-term allograft outcome of patients included in a prospective randomized clinical study conducted in our center 15 years ago by comparing two strategies: (A) horse antilymphoblast globulin (ALG) given at 10 mg/kg on alternate days to a maximum of 6 doses with low-dose CsA started at 8 mg/kg per day and prednisone at 0.25 mg/kg per day, versus (B) CsA started at 15 mg/kg per day and prednisone at 0.5 mg/kg per day. Diabetic and highly sensitized patients (PRA > 70%) were excluded from the study. RESULTS: The characteristics of the 50 patients enrolled in each group were not different. Although patient survival was not different (88% in group A vs 77% in group B), recipients treated with ALG showed a lower incidence of acute rejection episodes (20% vs 44%, P = .01) and better death-censored renal allograft survival (57% vs 41%, P = .03). Among rejection-free patients, graft survival was 15% higher in group A (60% vs 45%, P = .12). Multivariate Cox regression analysis showed that an acute rejection episode (relative risk [RR]: 2.44, 95% confidence interval [CI] 1.36-4.39; P = .0029) rather than ALG immunosuppression (RR 0.74, 95% CI 0.41-1.33; P = NS) was an independent predictor of death-censored graft survival. CONCLUSIONS: In summary, we confirmed that concomitant induction therapy with ALG, CsA, and steroids improves long-term renal allograft survival.  相似文献   

10.
These experiments compared the effect of a five-day course (days - 1 to +3) of cyclosporine therapy coupled with pretransplant (day - 1) administration of donor-specific antigen (whole blood or splenocytes) on either pancreatic or heart allograft survival in the Buffalo to Lewis rat donor-recipient combination. CsA therapy alone significantly (P less than 0.001) prolonged both heart (16.2 +/- 1.6 days) and pancreas (12.5 +/- 1.5 days) graft survival when compared with nonimmunosuppressed control heart and pancreas grafts (7.7 +/- 1.8 and 7.9 +/- 1.0 days, respectively). Pretransplant transfusion with either 2 ml of BUF whole blood or 2 x 10(8) red cell-free splenocytes on day -1 also resulted in a significant (P less than 0.001) prolongation of heart survival (14.0 +/- 1.2 and 14.0 +/- 1.6 days, respectively) but did not improve pancreas allograft survival (9.4 +/- 1.5 and 8.5 +/- 1.0 days, respectively). Combination CsA and antigen therapy further improved heart graft survival to 26.5 +/- 6.1 days (whole blood) and 28.8 +/- 5.8 days (splenocytes) but did not improve pancreas graft survival over that of CsA therapy alone. Extension of CsA therapy by adding two additional 3-day cycles on days 10-12 and 17-19 further improved heart graft survival both after CsA alone (35.2 +/- 3.2 days) and after CsA coupled with whole-blood transfusion (45.3 +/- 8.6 days), but did not have a salutary effect on pancreas allograft survival. Portal vein administration of donor antigen was equally effective as systemic inoculation in prolonging heart graft survival when the splenocytes were given alone (11.6 +/- 1.7 days). Conversely, pancreas allograft survival was not beneficially effected by portal antigen administration whether or not CsA was given. These data demonstrate the ability of pretransplant donor-specific antigen administration and short-term CsA therapy to significantly prolong rat heart allograft survival across a strong MHC histocompatibility barrier-but, surprisingly, they also demonstrate the failure of this regimen to have a salutary effect on pancreas allograft survival.  相似文献   

11.
Many recent reports have emphasized the importance of donor antigens in the induction of allograft tolerance. This study examines the effect of pretransplant infusion of 10(8) donor leukocytes (DL) combined with peritransplant cyclosporine (CsA) on W/F cardiac allograft survival in Lewis rats. Peritransplant recipient treatment consisted of CsA 20 mg/kg given i.m. on days 0, +1, and +2 relative to heart transplantation. Lewis recipients, 5-8 per group, were pretreated with 10(8) DL with or without peritransplant CsA. A single DL transfusion on day -3 or day -7 prior to transplantation significantly prolonged the mean survival time (MST) of W/F hearts from 7.0 +/- 0.9 days in controls to 12.2 +/- 4.5 days and 12.4 +/- 1.0 days (P less than 0.01), respectively. Two DL infusions on days -7 and -3 or on days -14 and -7 prolonged the MST to 10.6 +/- 1.3 days (P less than 0.02) and 16.4 +/- 2.8 days (P less than 0.001), respectively. The administration of peritransplant CsA alone significantly prolonged W/F heart allograft survival to 43.1 +/- 2.7 days. When pretransplant DL transfusion on day -3 was combined with CsA treatment, 4/8 animals maintained their grafts indefinitely (greater than 100 days). Similarly, DL infusion on day -7 with peritransplant CsA led to indefinite graft survival in 3/5 animals. Administration of DL on days -7 and -3 combined with CsA resulted in indefinite graft survival (greater than 100 days) in 4/6 animals. Transfusion of DL on day -3 alone or in combination with peritransplant CsA, had no effect on a third-party (ACI) heart allograft survival prolongation compared with appropriate controls. To define the underlying mechanisms responsible for donor-specific unresponsiveness in this model, pooled sera and unseparated spleen cells were passively transferred from recipients of long-term cardiac allografts to syngeneic rats receiving donor-type (W/F) or third-party (ACI) cardiac allografts. Transfer of serum (1 ml on days 0, and 1, 0.5 ml on days +2, +3, and +4) from ungrafted recipients of DL on days -14 and -7 led to significant donor graft survival of 9.8 +/- 0.4 days (P less than 0.02) in unmodified hosts. Similarly, passive transfer of serum obtained at 20 and 100 days after transplantation significantly prolonged the MST of donor-type hearts in syngeneic untreated hosts to 11.3 +/- 0.8 and 10.0 +/- 1.1 days, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

12.
In patients with delayed graft function (DGF), the use of cyclosporine (CsA) has been reported to prolong DGF, increase the number of required dialyses, increase the duration of hospitalization, and be associated with decreased graft survival. Routine postoperative antilymphocyte globulin (ALG) use has been advocated, but ALG is associated with increased viral infection. We studied outcome of individualization of immunosuppression. Between 11/84 and 8/86, first-cadaver transplant recipients whose serum creatinine (Cr) fell greater than or equal to 30% in the first 24 hr (immediate function) were started on CsA and prednisone (P) (group 1, n = 26). The remainder were randomized to P and azathioprine (group 2, n = 32) or P and ALG (group 3, n = 26), and switched to CsA when serum Cr fell greater than 30% (minimum 5 days ALG for the ALG group). P taper was the same in all groups. Patients with DGF (groups 2 and 3) had longer preservation time and higher peak PRA (P less than .05) than group 1. Groups were otherwise equivalent. One and 2-year patient survival was 96% (3 cardiovascular deaths; all with functioning grafts). One-year graft survival was 87% for group 1, 87% for group 2, and 82% for group 3(NS). In patients requiring dialysis, mean day off dialysis was 12 +/- 3 in both groups 2 and 3. Mean hospital stay was 12.5 +/- 1.3 days for group 1, 21.6 +/- 2.1 days for group 2 (P less than .05 vs. 1 & 3), and 14.5 +/- 1.2 days for group 3 (NS vs. 1). The increased hospital stay for group 2 patients was mainly due to increased in-hospital rejections: 75% for group 2, (P less than .05 vs. group 1 [35%], and group 3 [11.5%]). In addition, more group 2 in-hospital 1st rejections were steroid resistant as compared to group 1; 46% group 1 patients have remained rejection free as compared to 0% group 2 (P less than .05 vs. 1 and 3) and 35% of group 3 (P less than .05 vs. 1 and 2). Mean serum creatinine at 6-12 months remained higher in patients with DGF (group 1 P less than .05 vs. 2 and 3). Rejection was the major cause of graft loss in all groups.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
Previous studies from our laboratory showed that pretransplant conditioning with fresh donor-specific blood (DST) combined with cyclosporine (CsA) resulted in long-term prolongation of ACI heterotopic cardiac allografts in LEW recipients treated with subtherapeutic doses of CsA. The concomitant administration of CsA profoundly reduced but did not eliminate the DST-induced sensitization. The purpose of the present study was to investigate in the ACI-to-LEW cardiac allograft model whether heat-treatment of the blood would further reduce the sensitizing potential of DST while maintaining their benefits in our protocol. Fresh heparinized ACI blood was heated at 45 degrees C for 60 min. Then 1.5 ml was administered i.v. to LEW rats on day -8 with respect to grafting (day 0). Controls received heat-treated BUF blood. Donor heat-treated blood (HT-DST), unlike fresh blood, did not induce a humoral cytotoxic response and resulted in the prolongation of cardiac allograft survival (13.2 +/- 2.7 vs. 7.2 +/- 1.0; P less than 0.01). Treatment of HT-DST recipients with postoperative subtherapeutic doses of CsA (2.5 mg/kg/day x 30) extended graft survival (46.6 +/- 22.0 vs. 7.7 +/- 2.0 days; P less than 0.01). The combined pretransplant administration of HT-DST and CsA followed by posttransplant subtherapeutic doses of CsA led to long-term prolongation of cardiac grafts (122.0 +/- 73.0 vs. 31.7 +/- 22.0 days; P less than 0.01). These studies demonstrate that heat-treatment of allogeneic blood eliminates the humoral responses to DST and actually enhances their beneficial effects in terms of graft survival. Such effects can be dramatically increased by CsA. The possible mechanism of these phenomena are discussed.  相似文献   

14.
An attempt was made to reveal the role of Ia-positive cells in the beneficial effect of pretransplant donor-specific blood transfusion (DST) and induction of suppressor cells in the cardiac allotransplantation of rats. Mean graft survival time (MST) of F344 (RT1 1v1) hearts transplanted in WKA (RT1k) rats was 6.5 +/- 0.8 days. Pretreatment of recipients with 1 ml DST 10 days before grafting prolonged it to 56.5 +/- 38.1 days. Plasma or erythrocytes did not prolong MST at all, whereas pretreatment with 1 X 10(7) lymphocytes prolonged MST significantly. B enriched cells separated on a nylon-wool column prolonged MST, but T-enriched cells did not. Treatment of lymphocytes with interspecies crossreactive monoclonal anti-Ia antibody and complement eliminated the ability of lymphocytes to prolong MST, suggesting an important role of Ia-positive cells in the beneficial effect of DST. The role of Ia-positive cells in prolonging graft survival, was analyzed by a cell and serum transfer experiment. MST of F344 heart allografts transplanted in sublethally irradiated (500 rads) WKA rats was 17.4 +/- 4.0 days. MSTs of allografts in rats irradiated and treated with serum or spleen cells of blood-conditioned rats were 23.2 +/- 1.6 (P less than 0.05) and 5.2 +/- 0.7 (NS) days, respectively. On the other hand, MSTs of the grafts in rats irradiated and treated with serum or spleen cells harvested from rats that had accepted grafts for 30 days were 18.7 +/- 1.9 (NS) and 63.8 +/- 29.9 (P less than 0.01) days, respectively. The results indicate that the initial role of a serum factor in prolonging graft survival induced by DST containing Ia-positive cells was followed by activating suppressor cells by the presence of the allograft.  相似文献   

15.
A total of 127 haploidentical living-related transplants have been performed at our institution since March 1986. A donor-specific transfusion plus azathioprine protocol was used until July 1988 (n = 74) and a random transfusion (RT) protocol without AZA used thereafter (n = 53) in an effort to decrease risk of recipient sensitization and reduce the burden on the prospective donor. All patients were given cyclosporine 8 mg/kg/day orally beginning 1 week prior to transplantation. Immunosuppression was similar in both groups and consisted of triple induction therapy with prednisone, CsA, and AZA. A positive T cell crossmatch eliminated the potential donor. Seven individuals (9.6%) were sensitized in the DST group and 1 (1.9%) in the RT group, leaving 67 and 52 patients in the two groups of the study, respectively. Groups were similar with respect to age, sex, history of pregnancy in female patients, peak and baseline panel-reactive antibody (PRA), DR match, and prior transplants. The groups differed slightly with respect to AB antigens shared, with an advantage in the RT group. Actuarial graft survival was not statistically significantly different between the two groups, with 2-year graft survival of 95% in the DST and 91% in the RT group (log rank, P = 0.16). Patients in the RT group had significantly more rejection episodes and had them sooner than their counterparts in the DST group. At the end of 1 year, 50% of patients in the DST group had at least 1 rejection episode, compared with 75% of patients in the RT group (P = 0.0008). Multivariate (Poisson) analysis of 10 variables was performed, with an overall model P-value of 0.0001. Only DST (P = 0.0001) and pregnancy (P = 0.015) were significant predictors of rejection episodes, both protective. The difference in rejection episodes and the timing with which they occur has not yet translated into a significant difference in graft survival between DST and RT groups.  相似文献   

16.
BACKGROUND: Immunosuppressive drugs continue to pose significant risks such as infection, toxicity, or neoplasia when used in long-term therapy. The investigation of newer and safer combined treatment strategies that decrease the need for these drugs is becoming increasingly important. Immunonutrients are known to have significant modulating effects on the immune system. Feeding with Impact, a commercially available diet enriched with arginine, omega-3 fatty acids, and RNA, recently has been shown to extend rat cardiac allograft survival when combined with a donor-specific transfusion (DST) and cyclosporine A (CsA). Because mycophenolate mofetil (MMF) is now commonly used in the clinical setting, the current study was designed to examine the effect on rat cardiac allograft survival when MMF was added to this immunosuppressive regimen. METHODS: Intra-abdominal ACI to Lewis heterotopic cardiac allografts were performed. Study groups included untreated controls and recipients receiving varying combinations of a DST (1 mL) on the day prior to engraftment, MMF 45 mg/kg/day from the day of transplant through postoperative day six, and CsA 10 mg/kg on the day prior to operation and 2.5 mg/kg from the day of transplant through postoperative day 6. Animals were fed ad libitum with Impact diet or standard lab chow. Graft survival was determined by cessation of a palpable heartbeat. RESULTS: Treatment with MMF led to a prolonged allograft survival over historical untreated controls. The combination of MMF with a donor-specific transfusion, Impact, or CsA was associated with an increase in graft survival over MMF alone. The addition of Impact to the combination of MMF and CsA resulted in further improvement. The most pronounced graft survival advantage was seen when Impact was combined with a DST and both of the immunosuppressive agents. One quarter of the animals in this group had a palpable donor heart beat at greater than 150 days, indicating functional tolerance in those animals. CONCLUSIONS: The administration of Impact diet to treatment groups in this study was associated with graft survival advantages when compared to most of the other study groups receiving a similar drug regimen and standard chow. These findings support the importance of nutritional influences on allograft survival, and highlight the potential of diet therapy when used with short courses of clinically relevant immunosuppressive drugs.  相似文献   

17.
Donor specific blood transfusion (DST), given prior to living related kidney transplantation has resulted in significant improvement in graft survival. This improvement, however, has been accomplished with a high rate of adverse sensitization against the donor. In an attempt to reduce the incidence of sensitization, we have employed DST with intermittent coverage of cyclophosphamide. A comparative study was done between 2 methods of DST with or without the coverage of immunosuppressant for prospective kidney transplant recipients from living related donors. In addition, the beneficial effect of DST on graft survival was evaluated in our recent series of living related transplantation using cyclosporine A (CsA) as postoperative immunosuppression. Twenty-nine prospective kidney transplant patients received 200 ml of fresh whole blood 3 times at 2 week intervals from HLA one-haploidentical living related donors. The first 13 patients received DST alone, while the remaining 16 were given cyclophosphamide (CPM 1.5 mg/kg/day) for 3 days prior to each DST. In patients with CPM coverage, 6.3% (1 of 16) developed positive T-warm antibody against donor and 15% of patients (2 of 13) with DST alone developed it. Like-wise 19% (3 of 16) of the former and 38% (5 of 13) of the latter became positive B-warm crossmatch. The difference in sensitization rates between these 2 groups was not statistically significant. Nineteen patients receiving DST were compared to 21 non-DST patients in incidence of acute rejection, graft function and graft survival with the same immunosuppressive regimen, such as CsA, prednisolone, and mizoribine.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
We studied 46 living-related primary renal allograft recipients between June 1980 and Jan 1988 to determine if enhancement of allograft survival by donor specific transfusions requires a major histocompatibility complex mismatch between the blood/kidney donor and the recipient. Recipients were matched for a single HLA haplotype, but differed at various HLA loci on the unshared haplotype. DST (200 ml) was administered either 3 times at two-week intervals pretransplant (n = 17), or once 3-4 weeks pretransplant, together with oral azathioprine (1 mg/kg/day/28 days) (n = 29). Patients were followed for at least 1 year and all clinical rejection episodes were confirmed histologically. Enhanced graft survival by DST was defined as a rejection-free posttransplant course. Incompatibility for class II determinants on the unshared haplotype of donor had a beneficial effect. A significantly greater proportion of recipients had stable, rejection-free, allograft function if incompatible for the DR locus (80% vs. 44%, P = 0.012), for class II public determinants (100% vs. 58%, P = 0.013), or for at least one of the class II gene products (DR, DQ, class II public) (81% vs. 40%, P = 0.006). Graft loss occurred in 7 of 46 (15%); 6 of the 7 recipients were HLA class II-compatible with their blood/kidney donor. Mismatches for HLA class I private or public determinants and other factors known to affect graft outcome did not influence the results. We conclude that enhanced kidney allograft survival by DST may be predicated by factors within the MHC--specifically class II disparity. These observations also suggest that better HLA matching at the class II locus may account for the apparent "disappearance" of the transfusion effect in cadaver renal transplants in the cyclosporine era.  相似文献   

19.
Pre-transplant blood transfusions are given as a means of desensitization to reduce the required dose of cyclosporin A (CsA). In this study, the effect of pretransplant blood transfusion on host survival and T-cell function against alloantigen were investigated. Male Lewis rats (RT11) were used as the recipients in all experiments, and male DA rats (RT1a) were used as the blood and small bowel donors, and as a source of allogeneic stimulator cells. Male BUF rats (RT1b) were used as donors of third party blood, and of allo-stimulator cells in a delayed-type hypersensitivity (DTH) response. In our experimental design, Lewis rats were divided into the following groups according to the type of administration: (1) a donor-specific blood transfusion (DST) 8 days preoperatively and a concurrent 5-day course of CsA at 10 mg/kg per day; (2) a nonspecific third party blood transfusion (NST) and CsA at 10 mg/kg per day from day 8 to day 4 preoperatively; (3) CsA alone from day 8 to day 4 preoperatively; (4) DST alone 8 days preoperatively; or (5) no treatment, being the control group. Postoperative treatment consisted of CsA at 2.5 mg/kg per day for 30 days. Rats conditioned with NST plus CsA, CsA alone, DST alone, and the untreated control rats survived for 7.2 ±1.2, 9.0 ± 2.2, 6.8 ± 0.4, and 7.4 ± 1.6 days, respectively. In contrast, the five rats conditioned with DST plus CsA survived for 100 days or more. This study demonstrates that long-term survival of a small bowel allograft can be achieved by host-conditioning with a combined treatment of DST and low-dose CsA.This paper was presented at the 10th Congress of the Asian Association of Pediatric Surgeons held in Seoul, Korea from March 26–29, 1990, and at the 90th Annual Meeting of the Japanese Surgical Society held in Sapporo, Japan in 1990.  相似文献   

20.
Tumor necrosis factor (TNF) levels have been reported to be elevated during episodes of human renal, hepatic, and cardiac transplant rejection. In addition, we have shown polyclonal anti-TNF antibodies to have immunosuppressive effects. The present study was performed to evaluate the efficacy of a monoclonal anti-TNF-alpha antibody in rat cardiac transplantation as the sole immunosuppressant and in conjunction with low-dose cyclosporine (CsA). We also performed immunohistological studies to localize intragraft TNF and evaluate graft infiltrating cells (GICs), and we measured serum TNF levels by an ELISA. Untreated Buffalo to Lewis heterotopic rat cardiac transplants reject in 10.5 +/- 0.4 days. A 10-day induction course of CsA (2 mg/kg/day, po) prolonged survival to 16.7 +/- 2.7 days (P less than 0.05 vs control), and 10 days of anti-TNF (2000 U/day, ip) prolonged survival to 22.6 +/- 0.8 days (P less than 0.05 vs control). Combination of anti-TNF plus CsA synergistically prolonged graft survival to 40.7 +/- 1.8 days. Three-day courses of anti-TNF were moderately effective (13.7 +/- 0.5 days, P less than 0.05 vs control) and were also synergistic with CsA (27.8 +/- 2.2). Intragraft TNF localization using immunoperoxidase showed extensive perivascular and mononuclear cell staining in control hearts vs minimal staining in anti-TNF-treated groups. Likewise, serum TNF levels were significantly lowered for treated groups vs control (83.1 +/- 14.0 pg/ml for control; 39.5 +/- 13.8 for anti-TNF; and 13.4 +/- 5.4 for anti-TNF + CsA; P less than 0.05 vs control for all groups).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号