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1.
BACKGROUND: We designed an antisense phosphorothioate oligodeoxynucleotide (oligo) to specifically inhibit the expression of rat intercellular adhesion molecule-1 (ICAM-1) mRNA (IP-9125). METHODS: IP-9125 oligo was delivered intravenously by osmotic pump alone or in combination with cyclosporine (CsA) to recipients in order to prevent the rejection of kidney or heart allografts. In additional experiments, kidney allografts were perfused with IP-9125 before grafting. RESULTS: IP-9125 inhibited ICAM-1 mRNA and ICAM-1 protein expression in rat aortic endothelial cells; scrambled controls IP-12140 and IP-13944 were ineffective. Untreated ACI (RT1a) recipients rejected Lewis (RT1l) kidney allografts at a mean survival time of 8.5+/-1.1 days. A 14-day intravenous administration of 2.5 mg/kg/day IP-9125 prolonged the survival of kidney allografts to 39.2+/-16.4 days; 5.0 mg/kg/day, to 43.0+/-17.5 days; and 10.0 mg/kg/day, to 50.4+/-21.6 days. In contrast, a scrambled control IP-12140 was not effective. A combination of 10 mg/kg/day IP-9125 and 1.0 mg/kg/day CsA delivered for 14 days synergistically extended kidney allograft survival times 88.5+/-7.5 days. In contrast, the combination of 10.0 mg/kg/day control IP-12140 with CsA was ineffective (20.7+/-3.2 days) when compared with CsA alone (20.2+/-4.0 days). Similar results were obtained for heart transplants in recipients treated with IP-9125 alone or in combination with CsA. Furthermore, in situ immunostaining showed that IP-9125 significantly reduced the expression of ICAM-1 protein in kidney allografts. Finally, perfusion of kidney grafts alone with 20.0 mg per 2 ml of IP-9125 protected kidney allografts from rejection (37.5+/-7.5 days; P < 0.001), whereas perfusion with 20 mg per 2 ml of control IP-12140 was ineffective (12.6+/-5.0 days). CONCLUSIONS: Rat ICAM-1 IP-9125 oligo inhibits ICAM-1 protein expression in vitro and in vivo as well as blocks allograft rejection when used for pretreatment of donors, graft perfusion, or postoperative treatment of recipients.  相似文献   

2.
BACKGROUND: Mycophenolate mofetil (MMF; Cell-Cept) is a potent and selective inhibitor of B and T lymphocyte proliferation that has proven effective in reducing the incidence of acute rejection in cadaveric kidney transplant recipients in several randomized, blinded clinical studies. Because the frequency and characteristics of rejection episodes may be different and more severe after combined pancreas-kidney transplantation, we hypothesized that MMF would have a significant impact on pancreas-kidney rejection and graft outcome. Therefore, we compared the efficacy of MMF versus azathioprine (AZA) in cyclosporine-treated simultaneous pancreas-kidney transplantations. METHODS: A retrospective comparison of 358 consecutive primary SPK transplantations performed from 1990 to 1997 was conducted. Patients received either MMF (n=109, 3 g/day) or AZA (n=249, 2 mg/kg q.d.) in combination with cyclosporine-based immunosuppression. All patients received a quadruple-drug sequential induction protocol with either OKT3 or Atgam. Several outcome parameters, including patient and graft survival rates and frequency of rejection, were analyzed. RESULTS: MMF-treated patients demonstrated a markedly reduced rate of biopsy-proven kidney rejection (31 vs. 75% AZA, P=0.0001), clinically significant pancreas rejection (7 vs. 24% AZA; P=0.003), and steroid-refractory rejection (15 vs. 52% AZA; P=0.01). As a result, kidney and pancreas allograft survival was significantly better in MMF patients compared with AZA patients (2-year survival rates: kidney, 95 vs. 86%; and pancreas, 95 vs. 83%). Although surgical infections after transplantation were more frequent in MMF patients, MMF patients were more likely to have undergone enteric drainage. Importantly, we did not observe an increased incidence of any of the bacterial, fungal, or viral infections that typically plague immunosuppressed transplant recipients. CONCLUSIONS: This retrospective study demonstrates that MMF is a highly effective immunosuppressant in SPK transplantation. It is not associated with an increased risk of opportunistic infections when a balanced immunosuppressive management approach is used. MMF strikingly reduces the frequency of acute cellular and steroid-resistant rejection. As a result of this combined experience, it is not unexpected then that we observe significantly improved graft survival rates in MMF-treated SPK patients compared with patients receiving a more traditional immunosuppressive regimen.  相似文献   

3.
BACKGROUND: In renal transplantation the beneficial immunosuppressive effects of cyclosporin (CsA) may be curtailed by its nephrotoxicity, specially in patients receiving a cadaveric allograft from suboptimal donors or at risk of delayed graft function. Mycophenolate mofetil (MMF) and antithymocyte globulin (ATG) have each demonstrated to be potent immunosuppressants in renal transplantation. In a prospective analysis we have studied the results at 6 months of the combination of MMF, ATG and low-dose steroids in patients with low immunological risk receiving a first cadaveric renal allograft from a suboptimal donor or at risk of delayed graft function. METHODS: Patients with preformed reactive antibodies < 500% receiving a first graft from a suboptimal donor (age > or = 40 years, non-heart-beating, acute renal failure, arterial hypertension) or at risk of delayed graft function (cold ischaemia time > or = 24 h) were eligible for this open single-arm pilot trial. From September 1996 to March 1997 we recruited 17 patients. They were treated with MMF 2 g p.o. preoperatively, and after transplantation at 3 g/day; rabbit ATG i.v. at 2 mg/kg preoperatively, and 1.5 mg/kg/day the first day after transplantation, followed by four doses of 1 mg/kg on alternate days; prednisone was given at 0.25 mg/kg/day and reduced progressively to 0.1 mg/kg/day at 3 months. Primary outcomes were incidence of biopsy-proven acute rejection, delayed graft function, opportunistic infections, graft and patient survival, and the need for introduction of CsA treatment. RESULTS: delayed graft function occurred in two cases (12%). Four of 17 patients (24%) had a biopsy-proven acute rejection (2 grade I and 2 grade II) within the first 3 months after transplantation. CsA was added in two cases with grade II biopsy-proven acute rejection, and in one with grade I biopsy-proven acute rejection. In one patient MMF was replaced by CsA because of gastrointestinal intolerance. Mean serum creatinine 6 months after transplantation was 159+/-59 micromol/1. Cytomegalovirus tissue invasive disease occurred in one patient (6%). At 6 months follow-up all patients are alive with functioning allografts. CONCLUSIONS: These preliminary results suggest that in low-immunological-risk patients who receive a suboptimal renal allograft or at risk of delayed graft function, the combination of MMF, ATG, and steroids is an efficient immunosuppressive regime that may avoid the use of CsA in 70% of the recipients.  相似文献   

4.
BACKGROUND: In rodent transplant models, FTY720 exerts a synergistic affect with cyclosporine (CsA) to prolong allograft survival. The present experiments sought to test this combination in subhuman primates. METHODS: Cynomolgus monkeys were transplanted with kidney allografts that were incompatible in mixed lymphocyte culture reactions. The animals were treated with daily intramuscular injections of CsA using doses selected to maintain whole blood trough concentrations at therapeutic values between 40 and 200 ng/ml. The 4 experimental groups included CsA without or with 0.1, 0.3, or 1 mg/kg/day FTY720 delivered daily by intravenous bolus injection. Therapeutic effects were suggested both by the graft histology of biopsy within the first 10 posttransplant days and by the length of host survival. RESULTS: Whereas recipients treated with CsA alone rejected kidney allografts at a median survival time of 8.5 days (n=4), those treated with either 0.1 or 0.3 mg/kg/day FTY720 in addition to CsA showed significant prolongation of kidney allograft survival to 71 days (n=3; P<0.04) or 63 days (n=5; P<0.05), respectively. The hosts in the 1.0 mg/kg/day FTY720 group survived 48 days, with 2 of 5 recipients succumbing at 9 or 17 days postgraft, suggesting possible complications caused by overimmunosuppression. Biopsies of the 0.1 mg/kg/day FTY720 group on posttransplant day 7 documented mild to moderate rejection (grade I), indicated by multiple focal areas of tubular destruction. The histology results of transplants in the 0.3 or 1 mg/kg/day FTY720 group showed only minimal interstitial inflammatory infiltrates (borderline grade), with no evidence of tubular or arterial damage. Serum creatinine values among the animals in the 0.1 mg/kg/day FTY720 group showed increases in 2 of 3 recipients by day 20 and in the third by day 41 postgraft. Among the 0.3 mg/kg/day FTY720 group, 3 of 5 recipients maintained baseline creatinine values to 45 days postgraft; 1 recipient had stable kidney function for 120 days postgraft. CONCLUSIONS: Addition of FTY720 therapy to a subtherapeutic CsA immunosuppressive regimen delays the rejection of renal allografts in subhuman primates.  相似文献   

5.
OKT3 monoclonal antibody, a murine IgG2a monoclonal antibody targeting the T cell CD3 antigen, elicits a neutralizing humoral response in 20 to 50% of kidney transplant recipients when the concomitant immunosuppression consists of CsA-Sandimmun (SAND) and azathioprine (AZA). In the present study, we investigated the impact of the newer agents, CsA-Neoral (NEO) and mycophenolate mofetil (MMF) on OKT3 sensitization. Sixty-two consecutive kidney transplant recipients received prophylactic OKT3 (5 mg/d) from days 0 to 13, together with steroids. Concomitant immunosuppression consisted of either AZA + SAND (n=20), AZA + NEO (n=31), or MMF + NEO (n=11). The following doses were used: AZA, 2 mg/kg per d from days 0 to 13, then 1 mg/kg per d; MMF, 2 g/d starting on day 1; and CsA, either SAND or NEO, 6 mg/kg per d from day 6. At least two serum samples per month were available during the initial 3 mo for each patient. IgG anti-OKT3 antibodies were first evaluated by enzyme-linked immunosorbent assay. Patients were considered sensitized if their serum scored positive at a dilution > or = 1/1000. Peak titers of IgG anti-OKT3 antibodies and the incidence of patients harboring neutralizing anti-idiotypic antibodies were also determined. A first reduction in OKT3 sensitization was seen in patients receiving Neoral instead of Sandimmun (AZA + SAND: 10 of 20 [50%] patients sensitized versus 6 of 31 [19%] in the AZA + NEO group; P=0.03). This was probably related to the achievement of higher mean CsA trough blood levels in the NEO group during the first month (253+/-44 versus 186+/-49 ng/ml in SAND patients). Peak antibody titers and the proportion of patients with anti-idiotypic antibodies were similar in the AZA + SAND and AZA + NEO groups. A further reduction in the sensitization rate was observed with the replacement of AZA by MMF (MMF + NEO: 0% sensitized patients; P=0.0013). It is concluded that the combination of CsA-Neoral and MMF efficiently prevents sensitization against OKT3.  相似文献   

6.
BACKGROUND: Vesnarinone (VES) has been used for treatment of patients with congestive heart failure. In addition to inotropic effects, it seems to have immunosuppressive action. We tested the hypothesis that VES suppresses graft rejection, inotropic dysfunction caused by early rejection, and chronic coronary obstruction in a heterotopic rat cardiac transplantation model. METHODS: (1) To study acute rejection, hearts from Lewis-Brown Norway (LBN) rats were transplanted into Lewis rats, which were treated with or without VES (50 or 100 mg/kg/day orally). (2) In a functional study, LBN hearts with or without VES (100 mg/kg/ day) were isolated and perfused on day 3 after transplantation to assess inotropic response to isoproterenol (3 x 10(-8) M). (3) To study chronic rejection, Lewis hearts were transplanted into Fisher 344 rats, which were treated with or without VES (50 mg/kg/day) for 90 days. Coronary obstructive disease was assessed by morphometric analysis. There were five to six animals in each group. RESULTS: (1) VES (100 mg/kg/day) prolonged LBN heart survival (11.7 +/- 0.7 vs. 9.6 +/- 0.7 days in control; P < 0.05). (2) Left ventricular developed pressure was depressed in transplanted hearts regardless of VES treatment (84 +/- 12, 90 +/- 8 vs. 144 +/- 16 mmHg in untransplanted hearts; P < 0.01). The developed pressure after administration of isoproterenol in VES-treated hearts (184 +/- 20 mmHg) was higher than transplanted hearts without VES (118 +/- 16 mmHg; P < 0.05), and similar to untransplanted hearts (203 +/- 27 mmHg; P = NS). (3) Transplanted hearts treated with or without VES showed similar grades of rejection (2.0 +/- 0.3 vs. 2.6 +/- 0.2; P = NS), intimal area (6,996 +/- 3,186 vs. 13,441 +/- 5,165 microns2; NS), and coronary luminal obstruction (45 +/- 16% vs. 67 +/- 14%; NS). CONCLUSIONS: VES produces mild prolongation in survival of rat heart grafts, but has no significant effect on chronic graft atherosclerosis. VES preserves the positive inotropic effects of isoproterenol that are otherwise deteriorated by early acute rejection.  相似文献   

7.
BACKGROUND: Cyclosporine (CsA) nephrotoxicity can be identified by functional changes and chronic renal damage. CsA-associated renal fibrosis has been related to the overproduction of transforming growth factor (TGF)-beta1, a fibrogenic cytokine. Mycophenolate mofetil (MMF) may allow CsA dose reduction without increasing the risk of rejection. METHODS: We studied the impact of CsA dose reduction in association with MMF on renal function and TGF-beta1, production in 16 long-term renal allograft recipients with suspected CsA nephrotoxicity. Two grams/day of MMF were introduced, and CsA dose was reduced to reach whole-blood levels between 40 and 60 ng/ml within 1 month. CsA dose and levels, renal function parameters, and platelet-poor plasma TGF-beta1 levels were evaluated before and 6 months thereafter. RESULTS: MMF allowed a decrease in both the mean dose of CsA (3.8+/-1.35 vs. 2.2+/-0.73 mg/kg/day; P<0.01) and CsA levels (148+/-36 vs. 53+/-19 ng/ml; P<0.001). The reduction of CsA was associated with a decrement of serum creatinine levels (210+/-46 vs. 172+/-41 micromol/L; P<0.001) and an increase in both the glomerular filtration rate (32.9+/-12 vs. 39.1+/-14 ml/min/1.73 m2; P<0.02) and renal plasma flow (195+/-79 to 218.6+/-74.02 ml/min/1.73 m2; P<0.02). There was a reduction in plasma TGF-beta1 levels (4.6+/-4.2 vs. 2.0+/-1.4 ng/ml; P=0.003) and CsA levels correlated with TGF-beta1 (r=0.536, P=0.002). No rejection episodes occurred, and an improvement in both systolic (149+/-13 vs. 137+/-12 mmHg; P<0.01) and diastolic blood pressure (89+/-14 vs. 83+/-10 mmHg; P<0.04) were observed. CONCLUSIONS: These short-term results show that MMF introduction allows a CsA dose reduction, which improves renal function, reduces TGF-beta1 production, and improves the control of hypertension, without increasing the incidence of acute rejection.  相似文献   

8.
Cytokines and cytotoxic agents, including nitric oxide (NO) released by macrophages, play important roles during cardiac allograft rejection. In contrast to agents that suppress T-lymphocyte function, CNI-1493 is a multivalent guanylhydrazone compound that inhibits the synthesis and release of proinflammatory cytokines and NO from macrophages. This study investigated the effects of CNI-1493 on rejecting rat cardiac allografts by using Lewis to Wistar-Furth heterotopic cardiac transplants. CNI-1493 (2 mg/kg i.p., b.i.d.) or vehicle (water) was administered beginning the day before surgery. Rat cardiac allograft survival to cessation of heart beat, apoptosis of cardiac myocytes, degree of myocardial inflammation, and inducible nitric oxide synthase (iNOS) messenger RNA (mRNA), protein, and enzyme activity were studied at days 1, 3, 5, and 7 after transplantation. Allograft survival was increased significantly by 26% from 7.5 +/- 0.8 days in vehicle-treated rats (n = 6) to 9.5 +/- 1.2 days in CNI-1493-treated rats (n = 8, p < 0.05). Apoptotic cells per mm2 myocardium decreased from 2.25 +/- 1.25 to 0.84 +/- 0.49 at day 3 and 31.2 +/- 2.9 to 17.6 +/- 5.43 at day 5 after transplantation with CNI-1493 treatment (p < 0.05). The number of apoptotic myocytes and loss of cardiac muscle cells also decreased significantly at day 5 in the treated animals (p < 0.05). The reduction of myocyte loss at day 5 coincided with a significant decrease of the inflammatory response and reduced macrophage influx (p < 0.05). Myocardial iNOS mRNA, protein, and enzyme levels increased during the course of allograft rejection, and CNI-1493 did not significantly reduce iNOS expression in the rejecting rat allograft. CNI-1493 prolongs allograft survival and reduces myocyte loss, apoptosis, and inflammation during rat cardiac allograft rejection. These effects of CNI-1493 appear to be unrelated to altered NO synthesis but may be related to effects of the drug to inhibit macrophage synthesis of cytokines.  相似文献   

9.
The optimal dose of FK506 on rat limb allograft was investigated across the BN-to-F344 histocompatibility barrier. BN limb allografts were rejected in untreated F344 hosts within 11 +/- 1 days (mean +/- SD) after operation. A single injection of 0.5 mg/kg, 1.0 mg/kg, or 2.0 mg/kg of FK506 on the day of transplantation significantly prolonged graft survival, mean survival times (MST) based on gross sign of skin rejection were 16 +/- 1 days, 19 +/- 1 days, 21 +/- 1 days, respectively. Maintenance doses of 0, 0.25, 0.5, 1.0, or 2.0 mg/kg/week of FK506 after a single administration of 10 mg/kg of FK506 on the day of limb allograft prolonged the graft survival, 63 +/- 10, 68 +/- 20, 87 +/- 23, 98 +/- 30, 136 +/- 20 days, respectively, and showed no evidence of infection or toxic side effects. The regimen of lower maintenance dose of FK506, however, developed chronic GVHD. In the second set of experiments, development of peripheral blood chimeras was studied in PVG-to-ACl limb allograft model. A single injection of 50 mg/kg of the day of transplantation prolonged graft survival and MST was 154 days. The average rates of peripheral blood chimeras were 2 to 6% and there was no relationship between graft survival and peripheral blood chimeras. However, GVHD developed in one of the six recipients at 201 days after operation. In the similar experiments, grafts were irradiated before operation. Peripheral blood chimeras was not observed in there experiments and GVHD was not developed in 300 days after operation. These data suggest that FK506 is quite effective for rat limb allograft survival in dose-dependent manner and GVHD could be prevented by graft irradiation before operation.  相似文献   

10.
11.
BACKGROUND: 1,25-Dihydroxyvitamin D3, the hormonal form of vitamin D, is now believed to play a significant role in the immune responses, both in vitro and in vivo, preventing the development of several autoimmune diseases. These studies suggest that 1,25-dihydroxyvitamin D3 may be effective in prolonging allograph survival. METHODS: To test the hypothesis that 1,25-dihydroxyvitamin D3 would prolong allograft survival, neonatal heart grafts were transplanted to allogeneic recipients receiving either 19-nor-1,25-dihydroxyvitamin D2 (200 ng/day) or 1,25-dihydroxyvitamin D3 (50 ng/mouse/day) orally through the diet. The efficacy of 1,25-dihydroxyvitamin D3 in prolonging graft survival in a vascularized model was determined by heterotopic ACI to Lewis heart transplants. RESULTS: The provision of exogenous 1,25-dihydroxyvitamin D3 or an analog, 19-nor-1,25-dihydroxyvitamin D2, to mice markedly prolonged the survival of neonatal mouse heart allografts. Similar results were obtained with a vascularized heterotopic heart transplant model in rats. Cyclosporine at a maximum 25 mg/kg dose for mice proved less effective than 1,25-dihydroxyvitamin D3. Graft survival in mice differing at class I and class II loci (B10.A(4R) --> C57BL/10) increased from 13.0+/-1.1 days to 51.0+/-5.6 days and was significantly better than cyclosporine monotherapy (33.2+/-3.6). Rat heart survival in a high responder strain combination (ACI --> Lewis) increased from 6.2+/-0.3 to 25.2+/-2.8 days. The increased survival of the transplants brought about with 1,25-dihydroxyvitamin D3 was not accompanied by hypercalcemia in rats. CONCLUSION: These results suggest that 1,25-dihydroxyvitamin D3 can be used as an effective agent in preventing graft rejection.  相似文献   

12.
To compare regulatory effects of NOS2 in acute and chronic cardiac allograft rejection, we used NOS2 knockout mice as recipients in a cardiac transplant model. To study acute and chronic rejection separately but within the same genetic strain combination, we compared allografts placed into recipients without or with immunosuppression (anti-CD4/8 for 28 days). NOS2 mRNA and protein expression were compared using 32P-RT-PCR and immunohistochemistry. In our acute rejection model, NOS2 was predominately localized to graft-infiltrating immune cells. At day 7, grafts in NOS2-deficient recipients (n = 7) showed reduced inflammatory infiltrates and myocyte damage resulting in significantly lower rejection scores (1.6 +/- 0.4) compared to wild-type controls (n = 18; 2.8 +/- 0.2, P = 0.002). In contrast, in our chronic rejection model, additional NOS2 expression was localized to graft-parenchymal cells. At day 55, grafts in NOS2-deficient recipients (n = 12) showed more parenchymal infiltration and parenchymal destruction (rejection score 3.8 +/- 0.1) than wild-type controls (n = 15; 1.6 +/- 0.2, P < 0.0001). This was associated with a significant decrease in ventricular contractility (palpation score 0.3 +/- 0.1 compared to 2.3 +/- 0.3 in wild-type, P < 0.0001). Hence, NOS2 promotes acute but prevents chronic rejection. These opposing effects during acute and chronic cardiac allograft rejection are dependent on the temporal and spatial expression pattern of NOS2 during both forms of rejection.  相似文献   

13.
BACKGROUND: Mycophenolate mofetil (MMF), an inhibitor of lymphocyte proliferation, has been used to prevent allograft rejection. We investigated whether MMF also limits progressive renal injury in rats with 5/6 renal ablation, a model not primarily related to immunologic mechanisms. METHODS: Eighty-eight adult male Munich-Wistar rats underwent ablation and received either vehicle (N = 42) or oral MMF (N = 46), 10 mg/kg/day. Forty-seven sham-operated rats were also studied. RESULTS: Thirty days after surgery, remnant kidneys exhibited glomerular hypertension and hypertrophy. MMF treatment did not correct these abnormalities. Immunohistochemistry revealed interstitial lymphocyte infiltration 7 and 30 days after ablation. Proliferating cells abounded seven days after ablation, especially in tubules, declining in number along the following weeks. By contrast, the number of macrophages was moderately increased in the first weeks, attaining values eightfold as high as control 60 days after ablation. MMF attenuated these cellular events at all phases of the study. Sixty days after ablation, marked albuminuria, glomerulosclerosis and interstitial expansion were prominent in untreated rats. MMF treatment largely attenuated glomerular and interstitial injury without changing proteinuria. CONCLUSION: This is the first evidence that MMF may impact favorably on progressive renal diseases of "nonimmunologic" origin.  相似文献   

14.
FK-506 is a relatively new immunosuppressant similar in action to cyclosporine A, but is much more potent. Its primary action is against T lymphocytes, the major cellular component in corneal allograft rejection. The purpose of this study was the evaluation of the ability of topical and systemic FK-506 in preventing corneal xenograft rejection in an experimental animal model. Cross-species xenotransplants were used as the most vigorous stimulus to induce corneal rejection. Corneas derived from Hartley guinea pigs were transplanted into the left eyes of 32 male Lewis rats. Topical treatment was administered by using FK-506 0.3 mg/ml in a cyclodextrin suspension or vehicle (cyclodextrin suspension) four times per day. For systemic treatment, 0.5 mg/kg/day of FK-506 or vehicle (saline) was administered intraperitoneally. Treatments were started 60 minutes after surgery and continued for 21 days. The grafts underwent a double-masked examination, and a score was given for clarity, edema, and vascularization. The animals were sacrificed 21 days after transplantation. The control groups had allograft rejection after 6.75 +/- 0.31 (topical vehicle) and after 7.37 +/- 0.32 (systemic vehicle) days. The FK-506-treated groups showed allograft rejection after 14 +/- 0.88 (topical FK-506) or after 16.25 +/- 1.23 (systemic FK-506) days. In addition, FK-506-treated rats manifested less corneal neovascularization than control animals. We conclude that systemic or topical FK-506 is effective in prolonging xenograft survival in the rat keratoplasty model.  相似文献   

15.
Rapamycin (Rapa) monotherapy can promote renal allograft survival in dogs, but it is very toxic. To attempt to augment the effectiveness of Rapa and reduce its toxicity in a tolerance induction protocol, canine renal allograft recipients were treated briefly with antilymphocyte serum (ALS), donor bone marrow cells (BMC), and a limited course of cyclosporine (CsA). Rapa had little effect when CsA-treated recipients were given ALS on days -5 to -1 and BMC on day +1. When combined with CsA given days +13 to +42, ALS on days -5 to +7, and BMC on day +10, Rapa at 0.3 mg/kg on day +8 plus alternate days +15 to +39 significantly increased overall survival and was compatible with long-term survival after immunosuppression (6 grafts, 1 graft > 212 days, 1 graft > 470 days). Rapa appeared to prevent early rejections that can occur during treatment with these ALS/BMC/CsA protocols. Little toxicity of Rapa was observed with any treatment.  相似文献   

16.
BACKGROUND: Over the first 6 months after clinical transplantation, the incidence of rejection falls despite typically substantial decreases in maintenance immunosuppression. Despite this, chronic vascular rejection, manifested by an accelerated form of coronary artery disease is usually evident by the first annual angiogram and continues to progress over subsequent years. METHODS: To investigate this phenomenon further, peripheral blood mononuclear cells were prepared from blood samples obtained from 42 cardiac allograft recipients at 1 week, 3 months, and 6 months after transplantation and co-cultured with endothelial cells isolated and cultured from the aortas of their specific cardiac allograft donors. Donor-specific alloreactivity was assessed by (1) peripheral blood mononuclear cell proliferation (3H-thymidine incorporation) and (2) up-regulation of endothelial cell major histocompatibility complex class I and class II antigens and ICAM-1 expression (flow cytometry) at all three time points. RESULTS: Over this 6-month period, rejection incidence fell from 0.68 rejections/patient to 0.12 rejection/patient. Cyclosporine dose was reduced from 5.6 +/- 0.3 mg/kg (mean +/- standard error of the mean) to 4.5 +/- 0.2 mg/kg, prednisone dose was reduced from 0.58 +/- 0.08 mg/kg to 0.17 +/- 0.02 mg/kg, and azathioprine remained constant at approximately 2 mg/kg over the 6-month period. Despite this reduction in rejection and immunosuppression, no measure of in vitro donor-specific cell-mediated response to endothelial cells decreased over the 6-month time period. Peripheral blood mononuclear cell proliferation in response to donor-specific endothelial cells was unchanged between 1 week (916 +/- 139 counts/min [cpm]) and 3 months (896 +/- 135 cpm) and increased at 6 months (1738 +/- 243 cpm, p < 0.01). The increase in endothelial cell major histocompatibility complex class II expression in response to recipient peripheral blood mononuclear cells likewise was unchanged between 1 week (42.5 +/- 7.8 mean channel shift [mcs]) and 3 months (34.7 +/- 6.6 mcs) and increased substantially at 6 months (95.4 +/- 17.2 mcs, p < 0.02). The magnitude of the increase in endothelial cell major histocompatibility complex class I antigen and ICAM-1 expression in response to co-culture with recipient peripheral blood mononuclear cells did not change over the 6-month period. CONCLUSIONS: These data suggest an important dichotomy between cell-mediated responses to allograft parenchyma versus those to allograft vasculature and may provide an explanation for progressive vascular disease despite the absence of acute rejection.  相似文献   

17.
The purpose of this study was to evaluate the efficacy of local immunosuppression with intraportal administration of cyclosporine (CsA) in liver transplantation. Mongrel dogs weighing 12-18kg were used. Orthotopic liver transplantation was performed, and animals were divided to the following groups. Group I (n = 7): no treatment, group II (n = 7): CsA 5mg/kg/day intermittent iv, group III (n = 5): CsA 3mg/kg/day continuous iv and group IV (n = 8): CsA 3mg/kg/day continuous portal infusion. Immunosuppressive treatments were carried out for two weeks postransplant. Median survival time (MST) of group IV was significantly prolonged (MST = 18 days, range 10-85 days; p < 0.025) compared with group I (7 days, range 6-13), group II (10 days, range 7-16) and group III (7 days, range 6-10). Data of blood chemical analyses showed that hepatic dysfunction was significantly diminished in group IV compared with other groups (p < 0.05). Blood concentration of CsA on the 5th day (mean +/- SEM) was significantly lower in group IV (238 +/- 22ng/ml) than in group III (438 +/- 113ng/ml). Histologic findings showed that rejection reaction was effectively suppressed in group IV, although SG2M% (mean +/- SEM) of peripheral mononuclear cells of group IV (10.6 +/- 3.3%) was equal to that of group III (11.3 +/- 1.7%). In conclusion, local immunosuppression could achieve prominent effect in preventing hepatic graft rejection with limited systemic immunosuppression.  相似文献   

18.
BACKGROUND: Mycophenolate mofetil reduces episodes of biopsy-proven acute cellular rejection or treatment failure in the first year after kidney transplantation; however, limited data exist regarding the efficacy after lung transplantation. METHODS: In a 2-center, nonrandomized concurrent cohort study (level III evidence), we analyzed the incidence of biopsy-proven acute cellular rejection (International Society for Heart and Lung Transplantation grade > or=A2) and decrement in pulmonary function during the first 12 months after successful lung transplantation. All patients received induction immunosuppression with antithymocyte globulin (< or=5 days' duration), cyclosporine and prednisone, in addition to either mycophenolate mofetil (2.0 g/d) [n=11] or azathioprine (1 to 2 mg/kg per day) [n=11]. RESULTS: During the first 12 months after lung transplantation, the mycophenolate mofetil group experienced significantly fewer episodes of acute cellular rejection than the azathioprine group (0.26+/-0.34 vs 0.72+/-0.43 episodes/100 patient-days [mean+/-SD], p < 0.01; 95% CI for the difference=0.126 to 0.813). The change in forced expiratory volume -1 second [deltaFEV1] (liters) between the 3rd and 12th months after lung transplantation was analyzed for the two treatment groups. For this interval, deltaFEV1 for the mycophenolate mofetil group was +0.158+/-0.497 L vs -0.281+/-0.406 L for the azathioprine group (p < 0.05; 95% CI for difference=+0.0356 to 0.843). During the first year, there was 1 death in each group attributed to bronchiolitis obliterans syndrome with concurrent pneumonia. There were no differences in incidence of cytomegalovirus or bacterial infections between the treatment groups; however, a higher prevalence of aspergillus sp airway colonization in bronchoalveolar lavage fluid was observed for the mycophenolate mofetil group (p < .05). The prevalence of bronchiolitis obliterans syndrome at 12 months was 36% for the azathioprine group vs 18% for the mycophenolate mofetil group (p=NS). CONCLUSIONS: Our preliminary experience with mycophenolate mofetil after lung transplantation suggests a decreased incidence of biopsy-proven acute cellular rejection. Furthermore, less decline in FEV1 after 12 months may suggest a reduced incidence or delayed onset for development of bronchiolitis obliterans syndrome. Prospective randomized trials with low beta error (level I evidence) should be performed to assess the efficacy of mycophenolate mofetil vis-à-vis acute allograft rejection and bronchiolitis obliterans syndrome.  相似文献   

19.
BACKGROUND: It is commonly believed that abnormal blood glucose levels indicate irreversible rejection. We were interested in determining the stage at which rejection remains reversible. METHODS: A total of 54 Lewis rats were rendered diabetic with 55 mg/kg streptozocin and were then given a pancreas transplant from Brown Norway donors. Pancreatic juice was collected in a subcutaneous reservoir. All recipients received 15 mg/kg cyclosporine A (CsA) for 5 days. CsA was then discontinued for 2 days (n=7, group 1), 4 days (n=7, group 2), 6 days (n=9, group 3), 8 days (n=9, group 4), 9 days (n=11, group 5), and 10 days (n=11, group 6). Two animals of each group were euthanized at the end of the immunosuppressive-free interval, for histological assessment of the grade of rejection (G0, GI, GII, GIII). Rejection was treated with methylprednisolone (7 mg/kg body weight) and CsA (15 mg/kg body weight). The volume of pancreatic juice, together with juice cytology (C0, CI, CII) and blood glucose levels, was assessed daily. RESULTS: Blood glucose remained normal throughout the observation period in animals with GI and GII rejection. The numbers of animals that became diabetic were as follows: 5 of 9 (group 4), 7 of 11 (group 5), and 8 of 11 (group 6). Decreased amounts of pancreatic juice were observed in all animals, except those in group 1. The histology returned to normal after anti-rejection therapy in four animals (57%) of group 1, in two animals (28%) of group 2, and in one animal (11%) of groups 3 and 4, respectively. Although there was no animal in groups 5 and 6 with normal graft histology after treatment, there were still four (36%) and three (27%) animals, respectively, that were normoglycemic and that had pancreatic grafts with well-preserved islets. CONCLUSIONS: From these data, we conclude that even GIII rejection with severe endothelialitis and isleitis can be reversed. Therefore, we suggest that a trial of enhanced immunosuppression is justified in patients with advanced pancreas allograft rejection.  相似文献   

20.
BACKGROUND: Mycophenolate mofetil (MMF) has been previously shown to prevent functional deterioration in an experimental model of chronic renal allograft rejection. METHODS: In this retrospective case-control study, patients with chronic rejection who were receiving cyclosporine or tacrolimus and who had MMF added to their immunosuppressive regimen were compared with patients with chronic rejection who were not receiving MMF. Patients were matched for serum creatinine levels and transplant duration at the time MMF was begun. RESULTS: In the MMF group, the average dose of MMF was 1482 mg/day with an average duration of 19.3 months. Over 36 months, including 12 months before MMF and up to 24 months on MMF, there was no difference in serum creatinine levels between the two groups. Cyclosporine levels and dose were no different. CONCLUSIONS: In this small, retrospective, preliminary study, adding MMF to maintenance immunosuppression provided no clear benefit to renal allograft recipients with established chronic rejection. Larger prospective randomized studies are needed.  相似文献   

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