Recipient intramuscular gene transfer of active transforming growth factor-beta1 attenuates acute lung rejection

BACKGROUND: Gene transfer into the donor graft has been demonstrated to be feasible in reducing ischemia-reperfusion injury and rejection in lung transplantation. This study was undertaken to determine whether intramuscular gene transfer into the recipient can also reduce subsequent lung graft rejection. METHODS: Brown Norway rats served as donors and F344 rats as recipients. Recipient animals were injected with 10(10) plaque-forming units of adenovirus encoding active transforming growth factor beta1 (group I, n = 6), beta-galactosidase as adenoviral controls (group II, n = 6), or normal saline without adenovirus (group III, n = 6) into both gluteus muscles 2 days before transplantation. Gene expression was confirmed by enzyme-linked immunosorbent assay. Graft function was assessed on postoperative day 5. RESULTS: Successful gene transfection and expression were confirmed by the presence of active transforming growth factor beta1 protein in muscle and plasma. Oxygenation was significantly improved in group I (group I vs II and III, 353.6 +/- 63.0 mm Hg vs 165.7 +/- 39.9 and 119.1 +/- 41.5 mm Hg; p = 0.02 and 0.004). The muscle transfected with the transforming growth factor beta1 showed granulation tissue with fibroblast accumulation. CONCLUSIONS: Intramuscular adenovirus-mediated gene transfer of active transforming growth factor beta1 into the recipients attenuates acute lung rejection as manifested by significantly improved oxygenation in transplanted lung allografts. This intramuscular transfection approach as a cytokine therapy is feasible in transplantation and may be useful in reducing rejection as well as reperfusion injury.     

Transforming growth factor-beta (TGF-beta1) genotype and lung allograft fibrosis.

BACKGROUND: TGF-beta1 is a prosclerotic cytokine implicated in fibrotic processes. Fibrosis of the pulmonary parenchyma and airways is a frequent presentation in lung transplant recipients before and after transplantation. There are two genetic polymorphisms in the DNA sequence encoding the leader sequence of the TGF-beta1 protein, located at codon 10 (either leucine or proline) and at codon 25 (either arginine or proline). The codon 25 arginine allele is associated with higher TGF-beta1 production by cells activated in vitro. We tested the hypothesis that inheritance of alleles of the TGF-beta1 gene conferring higher production of TGF-beta1 may be responsible for over-expression of TGF-beta1 in transplant recipients resulting in lung allograft fibrosis. METHODS: We extracted DNA from leukocytes collected from 91 pulmonary transplants performed at our centre and 96 normal healthy volunteers between May 1990 and September 1995. Part of the first exon was amplified by PCR. Samples were genotyped by using sequence specific oligonucleotide probes. RESULT: The distribution of codon 10 alleles was similar in a normal healthy control group and in lung transplant recipients, regardless of their pretransplant lung pathology. By contrast, there was a significant difference in the frequency of codon 25 alleles between the control and transplant groups. In the normal control group 81% were codon 25 arginine/arginine (A/A) homozygotes, 19% were arginine/proline (A/P) heterozygotes and none were proline/proline (P/P) homozygotes. The distribution of codon 25 alleles was similar in lung transplant recipients who did not have a significant fibrosis in pretransplant pathology, but in transplant recipients who came to transplantation with lung fibrosis 98% (41 of 42 patients) were homozygous for the codon 25 A/A allele (p < .05). After lung transplantation 39 of 91 patients developed lung allograft fibrosis, and of these 92.3% (36 of 39 recipients) were of homozygous codon 25 A/A high TGF-beta1 producer genotype (p < .001). Lung transplant recipients who were homozygous for both codon 10 L/L and codon 25 A/A showed poor survival compared with all other TGF-beta1 genotypes (p < .03). CONCLUSION: Homozygosity for arginine at codon 25 of the leader sequence of TGF-beta1 that correlates with higher TGF-b production in vitro, is associated with fibrotic lung pathology before lung transplantation and with the development of fibrosis in the graft. In combination with the codon 10 leucine allele, homozygosity for the codon 25arginine allele is a marker for poor post-transplant prognosis and recipient survival.     

Chelerythrine ameliorates acute cardiac allograft rejection in mice

The improvement in graft survival over the past decade has been mainly due to calcineurin inhibitors, which interfere with the calcium-mediated pathway. Recently, other pathways such as those mediated by protein kinase C (PKC) are coming into view. The purpose of this study was to assess the immunosuppressive properties of chelerythrine, a specific PKC inhibitor, in preventing acute rejection in murine heterotopic heart transplantation. Mice were randomly divided into control and chelerythrine treated group. The control group received PBS while the chelerythrine treated group was given intraperitoneal injection doses (1, 5, 10 mg/kg) of chelerythrine from day 0 to day 14 after heart transplantation. Six days after transplantation, cardiac allografts were harvested for further tests. The mean survival time (MST) of the cardiac allograft in untreated animals was 8 days while graft MSTs observed in chelerythrine treated group was 13 and 23 days at 5 and 10 mg/kg treatment doses, respectively (P < 0.05). Histologic assessment of the allograft in chelerythrine group showed a significant decline in histologic rejection score, as well as CD4 + and CD8 + T cell infiltration and ICAM-1 + endothelial cell activation. Down-regulation of Th1/Th2 cytokine expression was observed in chelerythrine treatment group. Meanwhile, chelerythrine was also found to inhibit the dephosphorylation of phosphorylated nuclear factor of activated T cells (NFAT) protein 1 and 4.     

Fas ligand gene transfer combined with low dose cyclosporine A reduces acute lung allograft rejection

Abstract The interaction between Fas and its ligand (FasL) induces apoptosis in the Fas‐expressing cell. We hypothesized that liposome‐mediated FasL gene transduction to the lung allograft, in addition to low‐dose immunosuppression, might reduce acute rejection. Orthotopic left lung allotransplantation was performed in male rats (Brown Norway to Fischer F344). FasL gene transfer was performed by use of the plasmid pBCMGSNeo carrying the gene coding for murine FasL and the cationic liposome GL#67:DOPE. Six hundred and sixty micrograms of DNA in 250 μl H₂O and 0.5 μmol GL#67 in 250 μl H₂O were diluted to 5 ml with saline solution. This emulsion (20 °C) was instilled retro‐gradely through the left pulmonary vein after flushing with LPD solution (20 ml, at 4 °C). Subsequently, the graft was stored at 10 °C for 3 h. A single dose of cyclosporine A (CsA; 2.5 mg/kg i. m.) was given to all groups 48 h after the transplantation. In group 1 (n = 6), FasL/GL#67 was instilled as described. In group 2 (n = 5), GL#67 was given without DNA. Group 3 (n = 5) animals received CsA only. Five days after transplantation, gas exchange was assessed after exclusion of the contralateral native lung (FiO₂ = 1.0). Grafts were flushed with saline solution and fixed in formaldehyde for histological evaluation. No statistical difference in gas exchange (PaO₂) between the two control groups 2 (6.4 ± 0.4 kPa) and 3 (7.4 ± 0.4 kPa) could be detected 5 days postoperatively (P = 0.9). In contrast, grafts transduced with FasL (group 1) had significantly better gas exchange on postoperative day 5 (PaO₂: group 1 37.0 ± 10.6 kPa vs group 2 6.4 ± 0.41 kPa; P = 0.002). Two animals in group 1 revealed no or only minimal improvement in gas exchange. Histologically, all lung specimen of all groups showed signs of acute rejection (A2). Leukocyte infiltrates, rated by two independent observers, were less severe in all group 1 animals. Liposome‐mediated FasL gene transfer at the time of harvest in combination with low‐dose CsA reduces acute rejection in four out of six animals in this model of rat lung allotransplantation.     

Transforming growth factor-beta1 gene polymorphism in renal transplant recipients

BACKGROUND: Cytokine transforming growth factor (TGF) is involved in regulation of tissue repair after injury. More recently, TGF-beta1 codon 10 gene polymorphism has been shown to be associated with circulating TGF-beta levels. We tested whether TGF-beta1 genotype polymorphism was predictive of renal allograft function decline. PATIENTS AND METHODS: The study population consisted of 129 consecutive cadaveric or living related renal transplant recipients at our center between 1985 and 2001. The recipient TGF-beta1 genotype polymorphism was determined from peripheral blood leucocytes DNA. The primary endpoint was rate of glomerular filtration rate decline between the first year and the third year of transplant. RESULTS: Baseline glomerular filtration rate as estimated by MDRD study equation at 1 year measured 50+/-17 mL/min/1.73 m2. At the end of the 3-year follow-up period, 52 patients (40%) experienced biopsy-confirmed acute rejections. Frequency and severity of allograft rejection did not differ with TGF-beta genotypes. However, the decline in glomerular filtration rate was significantly greater in Leu/Leu (TT) than Leu/Pro (CT) recipients, 6.3+/-16.9 mL/min/1.73 m2 versus 0.1+/-10.2 mL/min/1.73 m2, p=0.04. CONCLUSION: Our results demonstrate that recipient TGF-beta1 codon 10 Leu/Leu homozygosity is a potential risk factor of kidney allograft function decline.     

In vivo adenovirus-mediated endothelial nitric oxide synthase gene transfer ameliorates lung allograft ischemia-reperfusion injury

OBJECTIVE: Nitric oxide regulates vascular tone, inhibits platelet aggregation, and inhibits leukocyte adhesion, all of which are important modulators of ischemia-reperfusion injury. This study aimed to determine the effects of endothelial constitutive nitric oxide synthase gene transfer on ischemia-reperfusion injury in a rat lung transplant model. METHODS: In group I, donor animals were injected intravenously with 5 x 10(9) pfu of adenovirus-encoding endothelial constitutive nitric oxide synthase. Groups II and III served as controls, whereby donor animals were injected with either 5 x 10(9) pfu of adenovirus encoding beta-galactosidase or saline solution, respectively. Twenty-four hours after injection, left lungs were harvested and preserved for 18 hours at 4 degrees C, then implanted into isogeneic recipients, which were put to death 24 hours later. Recombinant endothelial constitutive nitric oxide synthase gene expression was evaluated by Western blotting and immunohistochemistry. Lung grafts were assessed by measuring arterial oxygenation, myeloperoxidase activity, and wet/dry weight ratios. RESULTS: Western blotting confirmed the overexpression of endothelial constitutive nitric oxide synthase in lungs so transfected compared with controls. Twenty-four hours after reperfusion, mean arterial oxygenation was significantly improved in group I compared with group II and III controls (189.4 +/- 47.1 mm Hg vs 71.7 +/- 8.9 mm Hg and 67.8 +/- 12.2 mm Hg, P =.02, P =.01, respectively). Myeloperoxidase activity, a reflection of tissue neutrophil sequestration, was also significantly reduced in group I compared with groups II and III (0.136 +/- 0.038 DeltaOD/mg/min vs 0. 587 +/- 0.077 and 0.489 +/- 0.126 DeltaOD/mg/min, P =.001, P =.01, respectively). CONCLUSION: Adenovirus-mediated gene transfer with endothelial constitutive nitric oxide synthase ameliorates ischemia-reperfusion injury as manifested by significantly improved oxygenation and decreased neutrophil sequestration in transplanted lung isografts. Endothelial constitutive nitric oxide synthase gene transfer may reduce acute lung dysfunction after lung transplantation.     

Transforming growth factor-beta1 and prostate cancer

Transforming growth factor-beta1 (TGF-beta1) is an important regulator of the normal and malignant prostate. In the non-malignant prostate, TGF-beta1 stimulates cell differentiation, inhibits epithelial cell proliferation and induces epithelial cell death. TGF-beta1 is secreted into semen and here it is an important immunosuppressive factor. Prostate cancer cells express high levels of TGF-beta1 and it seems to enhance prostate cancer growth and metastasis by stimulating angiogenesis and by inhibiting immune responses directed against tumour cells. Prostate cancer cells frequently lose their TGF-beta receptors and acquire resistance to the anti-proliferative and pro-apoptotic effects of TGF-beta1. Accordingly, high expression of TGF-beta1 and loss of TGF-beta receptor expression have been associated with a particularly bad prognosis in human prostate cancer patients. TGF-beta1 also seems to be a mediator of castration-induced apoptosis in androgen dependent normal and malignant prostate epithelial cells. The ability of some prostate tumours to avoid castration-induced apoptosis is however not simply due to loss of TGF-beta receptor type I or II expression in the tumour cells, but may also be related to an inability of these cells to up-regulate TGF-beta receptor levels in response to castration or possibly due to defects downstream of the receptors. Short-term therapy-induced changes in the TGF-beta system in prostate tumours can probably be used to predict the long-term response to androgen ablation treatment. Further investigations into the TGF-beta system in the prostate are, however, needed to elucidate how alterations in this system affect the behaviour of prostate tumours, and if this system can be manipulated for therapeutical purposes.     

Recipient intramuscular cotransfection of transforming growth factor beta1 and interleukin 10 ameliorates acute lung graft rejection

OBJECTIVE: Multiple gene transfer might permit modulation of concurrent biochemical pathways involved in acute lung graft rejection. We investigated whether gene cotransfection into the recipient reduces acute lung graft rejection. METHODS: Brown Norway rats were used as donors, and F344 rats were used as recipients. Recipient animals were injected with saline (groups I/VI) or 1 x 10(10) pfu of adenovirus encoding beta-galactosidase (groups II/VII), transforming growth factor beta1 (groups III/VIII), interleukin 10 (groups IV/IX), or both transforming growth factor beta1 and interleukin 10 (groups V/X) into both leg muscles 2 days before transplantation (groups I-V) or at the time of harvest (groups VI-X). The Kruskal-Wallis test for rejection score and 1-way analysis of variance were used to compare groups. RESULTS: Oxygenation was significantly improved in the cotransfected groups treated 2 days before transplantation and at the time of harvest. Rejection scores were also reduced in the cotransfected groups. In group V cotransfection suppressed endogenous interleukin 2 but not interferon gamma and tumor necrosis factor alpha. CONCLUSION: Recipient intramuscular cotransfection of transforming growth factor beta1 and interleukin 10 suppressed interleukin 2 expression and provided a synergistic effect that reduced acute lung graft rejection. This approach might be applied to the clinical setting because transplant recipients could be treated at the time of implantation.     

Transforming growth factor-beta 1 gene polymorphisms and cardiovascular disease in hemodialysis patients

BACKGROUND: Atherosclerotic vascular disease is a leading cause of morbidity and mortality in patients with end-stage renal disease (ESRD) on maintenance hemodialysis (HD). Transforming growth factor-beta1 (TGF-beta1) is a multifunctional cytokine that inhibits the atheromatous process. We studied coding region polymorphisms of the TGF-beta1 gene (+869 T --> C at codon 10 and +915 G --> C at codon 25) as genetic susceptibility factors for prevalent vascular disease and cardiac outcomes in a cohort of HD patients enrolled in the HEMO Study. METHODS: Genotyping was carried out using polymerase chain reaction-sequence specific primer (PCR-SSP) methods with a cytokine genotyping tray. Prevalent vascular disease was coded from the Index of Disease Severity (IDS) scores for ischemic heart disease (IHD), peripheral vascular disease (PVD), cerebrovascular disease (CVD), and congestive heart failure (CHF), 0 indicating absence, and 1 to 3 increasing grades of severity. The presence of any vascular disease (VD) (i.e., any degree of IHD/PVD/CVD), and the number of coexistent vascular system diseases per patient were derived. Cardiac outcomes, one of the secondary outcomes of the HEMO Study, were expressed as a composite of the first hospitalization for, or death from, cardiac causes. RESULTS: The cohort consisted of 183 patients at enrollment, 56% male, 44% African American (AA), and 40% diabetic. The mean age was 62.4 +/- 12.2 years, and median dialysis vintage 2.02 years. The most frequent genotype at codon 10 was T/C (67%), and at codon 25 was G/G (72%). IHD was present in 52% of patients; 65% had at least one vascular system involvement, and 31% had 2 or more. On both univariate and multivariate analysis, the G/C genotype at codon 25 was significantly associated with the presence and extent of vascular disease at enrollment. The median time to cardiac outcome, defined as a composite of the first hospitalization for, or death from, cardiac causes, was 411 days in patients with the G/C genotype compared with 851 days in those with the G/G genotype (P= 0.03). Patients with the G/C genotype had a 1.6-fold increased hazard for cardiac outcomes after adjustment for baseline covariates (P= 0.04). CONCLUSION: The G/C substitution at codon 25 was associated with an increased risk for prevalent vascular disease, new onset cardiac morbidity, and cardiac mortality in HD patients, and may be a genetic susceptibility factor for the development of atherosclerosis. Further studies are required to evaluate the role of TGF-beta1 as a candidate gene.     

Pleural-changes in the lung allograft during acute rejection

Abstract To ascertain the cause of pleural fibrosis in lung allografts, pleural changes were investigated in rat syngeneic and allogeneic lung grafts. The pleura of lung syngeneic grafts showed no pathological changes except for mild edema on the first day after transplantation. In lung allografts, recipient cells migrated into the subpleural tissue early after transplantation (latent phase). In the vascuar phase, recipient lymphocytes in the subpleural tissue increased in number, while almost all alveolar structures were free from infiltration. Both CD4-positive and CD8-positive cells infiltrated in almost equal numbers with macrophages. The subsets of infiltrating cells were similar to those of the perivascular and peribronchial areas. In the late vascular or alveolar phase, fibro-blasts were observed among the infiltrating cells, and fibrotic changes started. In the destructive phase, collagen formation with marked pleural thickening was dominant. Pulmonary acute rejection should be treated at least up to the late vascular phase to prevent pleural fibrosis.     

结缔组织生长因子在大鼠移植肺急性排斥反应期的表达及意义

目的检测结缔组织生长因子（CTGF）在大鼠移植肺内的表达,并探讨其与移植肺纤维化关系。方法Wister大鼠15只为供体,SD大鼠15只为受体,进行原位左肺移植,1周后取其中10例移植肺标本作为实验组;10例健康Wister大鼠肺标本作为对照组,采用免疫组化方法检测CTGF在肺组织中的表达,同时采用HE及Van Gieson染色观察肺组织病理形态;并进行纤维化的半定量评分。结果移植肺组织内有大量炎性细胞浸润;肺间质纤维组织增生,部分肺泡组织破坏;CTGF在移植肺组织中有明显表达,而正常肺无表达。结论在肺移植术后的急性排斥反应期CTGF有明显表达,且可能参与移植肺纤维化的病理过程。     

冠状动脉灌注TGF-β1基因对异基因大鼠心脏移植物急性排斥反应的影响

目的 探讨经冠状动脉灌注重组腺病毒载体介导转化生长因子-β1(TGF-β1)基因转染对异基因大鼠心脏移植物急性排斥反应的影响.方法 建立大鼠颈部心脏移植模型,转基因组供心切取后经冠状动脉缓慢灌注含携带TGF-β1基因腺病毒载体(每克心肌组织5×1010PFU)的Stanford大学液,再植入受体颈部.空载体组灌注腺病毒空载体(每克心肌组织5 × 1010PFU)的Stanford大学液,对照组灌注无病毒的Stanford大学液.结果 转基因组的移植物内外源性TGF-β1基因和蛋白表达,移植物内CD68表达减少,心肌细胞凋亡减少,移植物急性排斥反应的始发时间明显推迟,程度较轻.结论 经冠状动脉灌注重组腺病毒载体介导TGF-β1基因转移可明显减轻异基因大鼠心脏移植物急性排斥反应.     

Vascular endothelial growth factor gene polymorphisms are associated with acute renal allograft rejection.

Acute rejection is a major cause of reduced survival of renal allografts. Vascular endothelial growth factor (VEGF) is a mitogen for endothelial cells and is expressed widely by renal tissue and T cells. VEGF influences adhesion and migration of leukocytes across the endothelium. This study investigates whether genetically determined variation in VEGF expression influences the development of renal allograft rejection. VEGF promoter polymorphisms were examined by using sequence-specific primer-PCR in 173 renal transplant recipients. Acute rejection occurred in 38.7%; median time to first rejection episode was 14 d. VEGF in vitro expression was investigated in stimulated leukocytes from 30 controls. The -1154*G and -2578*C alleles were associated with higher VEGF production. VEGF -1154 GG and GA genotypes were significantly associated with acute rejection risk at 3 mo (P = 0.004, odds ration [OR] = 6.8, 95% CI = 1.8 to 25 and P = 0.035, OR = 4.1, 95% CI = 1.1 to 15, respectively). Furthermore, VEGF -2578 CC and CA genotypes were associated with increased rejection risk (P = 0.005, OR = 4.1, 95% CI = 1.5 to 11.3 and P = 0.035, OR = 2.7, 95% CI = 1.1 to 7, respectively). These polymorphisms demonstrate linkage disequilibrium (P = 0.001). These data indicate that the -1154*G and -2578*C containing genotypes, encoding higher VEGF production, are strongly associated with acute rejection and may be useful markers of rejection risk.     

Lipid-mediated transbronchial human interleukin-10 gene transfer decreases acute inflammation associated with allograft rejection in a rat model of lung transplantation

BACKGROUND: Transferring genes with immunoregulatory capacity to transplanted organs has the potential to modify allograft rejection (AR). We examined the effect of ex vivo lipid-mediated transbronchial human interleukin-10 (hIL-10) gene transfer on acute AR in a rat model of lung transplantation. METHODS: Left single lung transplantations were performed between a highly histoincompatible rat combination: Brown Norway to Lewis. The extracted donor left lung was intrabronchially instilled with a plasmid encoding hIL-10 or Escherichia coli beta-galactosidase (control), mixed with a cationic lipid. On day 6 posttransplantation, the degree of AR was graded histologically (stages 1-4) based upon pathological categories of inflammation: perivascular, peribronchial, and peribronchiolar lymphocytic infiltrates, edema, intraalveolar hemorrhage, and necrosis. RESULTS: The stage of AR in the IL-10 group (3.1 +/- 0.4) was significantly lower than the control group (3.8 +/- 0.4). Pathological scores for edema, intraalveolar hemorrhage, and necrosis in the IL-10 group (2.3 +/- 0.8, 0.3 +/- 0.5, and 0.3 +/- 0.5, respectively) were also significantly decreased compared with those in the control group (3.2 +/- 0.4, 2.2 +/- 0.8, and 1.2 +/- 0.4, respectively). CONCLUSION: Ex vivo lipid-mediated transbronchial hIL-10 gene transfer attenuated acute inflammation associated with AR in a rat model of lung transplantation.     

The effect of FK778 on acute rat renal allograft rejection and expression of platelet-derived growth factor and transforming growth factor-beta

BACKGROUND: Acute rejection is the single most important risk factor for the development of subsequent chronic allograft nephropathy (CAN). Both platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) are major mitogens mediating mesenchymal cell proliferation and epithelial to mesenchymal cell transition. Early posttransplant induction of these growth factors may start molecular mechanisms leading to CAN. A new promising immunosuppressive drug, FK778, is an analogue of the active metabolite of leflunamide, which inhibits de novo pyrimidine biosynthesis. Herein we investigated the effect of FK778 on acute rejection and on the expression of PDGF and TGF-beta both alone and in combination with cyclosporine (CsA) or tacrolimus (Tac). METHODS: Kidney transplantations were performed from Dark Agouti (DA) to Wistar-Furth (WF) rats with syngeneic controls between DA rats. No immunosuppression was given to syngeneic grafts. Allografts were immunosuppressed with FK778 alone or in combination with CsA or Tac. Grafts were harvested on day 5 for histology and immunohistochemistry (PDGF-A, -B, PDGFR-alpha, -beta, TGF-beta1, and TGF-betaR1). RESULTS: FK778 ameliorated the inflammatory response and reduced PDGF and TGF-beta expression in a dose-dependent manner. It also showed synergy with calcineurin inhibitors, an effect that was stronger with Tac than with CsA. CONCLUSIONS: Our results indicated that FK778 decreased PDGF and TGF-beta expression early in acute rejection, suggesting it to be a promising therapy for CAN.