Striatal allografts in patients with Huntington's disease: impact of diminished astrocytes and vascularization on graft viability.

Neuronal transplantation has been proposed as a potential therapy to replace lost neurons in Huntington's disease. Transplant vascularization and trophic support are important for graft survival. However, very few studies have specifically addressed graft vascularization in patients with neurological disorders. In the present study, we analysed the vasculature of the host putamen and solid grafts of foetal striatal tissue transplanted into patients with Huntington's disease 9 and 12 years previously. Grafts were characterized by a significantly reduced number of large calibre blood vessels in comparison with the host brain. There were also significantly fewer astrocytes and gap junctions, suggesting a lack of functional blood-brain barrier components within the grafted tissue. Additionally, grafts demonstrated a nearly complete absence of pericytes (compared with the striatum) that are considered important for vascular stabilization and angiogenesis. Finally, the host striatum had a marked increase in atrophic astrocytes in comparison with controls and grafts. The extent to which the lower number of large calibre vessels and astrocytes within the transplants contributed to suboptimal graft survival is unknown. The marked increase in atrophic astrocytes in the host brain surrounding the grafts suggests that reduced host trophic support may also contribute to poor graft survival in Huntington's disease. A better understanding of the way in which these components support allografted tissue is critical to the future development of cell-based therapies for the treatment of Huntington's disease.

Roles of Toll-like receptors in allogeneic islet transplantation.

BACKGROUND: Toll-like receptors (TLRs) are involved in the rejection of solid organ allografts. However, the roles of TLRs in islets are still controversial. We investigated the roles of TLRs in donor islets together with those in recipients in allogeneic islet transplantation. METHODS: To assess the roles of TLRs in either donor islets or recipients, allogeneic islet transplantation was performed using myeloid differentiation factor 88 (MyD88)-knockout (KO), TLR4-KO, or Toll/interleukin-1 receptor domain-containing adaptor-inducing interferon-ß (TRIF)-KO mice. RESULTS: Both polyriboinosinic polyribocytidylic acid and lipopolysaccharide (LPS) stimulation induced the mRNA expression of regulated and normal T cell expressed and secreted, interferon-γ-inducible protein-10, monocyte chemotactic protein-1, interleukin-8, and inducible nitric oxide synthase in murine islets, whereas the induction was attenuated in TRIF-KO, interferon-ß promoter stimulator-1-KO, and TLR4-KO mice. When islets from MyD88-KO, TLR4-KO, or TRIF-KO C57BL/6 mice were transplanted to BALB/c recipients, graft survival was not better than that of wild-type (WT) islets. However, the survival of the MyD88-KO islet allograft was significantly prolonged when combined with anti-CD40L. In parallel, LPS stimulation in donor islets interfered with anti-CD40L blockade-mediated long-term survival of islet allografts in TLR4-KO recipients. LPS stimulation increased the perigraft infiltration of both T cells and macrophages. Then again, when islets from WT BALB/c mice were transplanted to MyD88-KO, TRIF-KO, or WT C57BL/6 mice, there was no difference in graft survival, although some of the MyD88-KO recipients obtained long-term graft survival. However, anti-CD40L prolonged graft survival significantly in MyD88-KO recipients. The absence of MyD88 in either donors or recipients decreased the perigraft infiltration of inflammatory cells when combined with anti-CD40L. CONCLUSIONS: TLRs in both donor islets and recipients are involved in islet allograft rejection.

Cellular senescence limits regenerative capacity and allograft survival.

Long-term graft survival after kidney transplantation remains unsatisfactory and unpredictable. Interstitial fibrosis and tubular atrophy are major contributors to late graft loss; features of tubular cell senescence, such as increased p16(INK4a) expression, associate with these tubulointerstitial changes, but it is unknown whether the relationship is causal. Here, loss of the INK4a locus in mice, which allows escape from p16(INK4a)-dependent senescence, significantly reduced interstitial fibrosis and tubular atrophy and associated with improved renal function, conservation of nephron mass, and transplant survival. Compared with wild-type controls, kidneys from INK4a(-/-) mice developed significantly less interstitial fibrosis and tubular atrophy after ischemia-reperfusion injury. Consistently, mice that received kidney transplants from INK4a/ARF(-/-) donors had significantly better survival 21 days after life-supporting kidney transplantation and developed less tubulointerstitial changes. This correlated with higher proliferative rates of tubular cells and significantly fewer senescent cells. Taken together, these data suggest a pathogenic role of renal cellular senescence in the development of interstitial fibrosis and tubular atrophy and kidney graft deterioration by preventing the recovery from injury. Inhibiting premature senescence could have therapeutic benefit in kidney transplantation but has to be balanced against the risks of suspending antitumor defenses.

[Vimentin and glial fibrillary acidic protein in the cells of ectopic neurotarnsplants of rat neocortex].

The purpose of this study was to investigate the expression of intermediate filament proteins (vimentin and glial fibrillary acidic protein--GFAP) in the cells of embryonic rat neocortex at different time points after its allotransplantation into injured sciatic nerve of adult animals. Using immunohistochemical methods, the differentiation of GFAP-positive astrocytes from vimentin-positive radial glial cells was observed in embryonic rat neocortex, grafted into sciatic nerve. It was shown that the differentiation of the embryonic neocortical astrocytes in the transplants took place a few days earlier than in the rat neocortex during normal ontogenesis. Reactive gliosis was demonstrated in the long-term transplants, as indicated by a large number of intensely stained GFAP-positive cells and vimentin-containing astrocytes. These findings suggest that ectopic neurotarnsplants could serve as a model for fundamental studies of the mechanisms of reactive gliosis development.

Fetuin-A pretransplant serum levels, kidney allograft function and rejection episodes: a 3-year posttransplantation follow-up.

BACKGROUND: Fetuin-A is a negative acute-phase protein, which acts as a potent calcification inhibitor and an antagonist of transforming growth factor-ß. Thus, fetuin-A levels are influenced by chronic inflammation and actively affect fibrosis and calcification processes, respectively. Graft rejection, interstitial fibrosis and tubular atrophy, chronic inflammation and calcification are common causes for kidney allograft loss. This study evaluated whether pretransplant fetuin-A levels predict long-term graft survival and rejection episodes in patients after kidney transplantation. METHODS: In 206 renal transplant recipients pretransplant fetuin-A levels were measured in serum by ELISA. During the 36 months' active follow-up (median 1,249 days) 13 patients died (94% patient survival) and renal allograft failure was reported in 18 patients (91% graft survival). RESULTS: Pretransplant fetuin-A levels did not differ among patients with incident graft failures as compared to patients with functional graft after long-term follow-up or rejection episodes (fetuin-A: 393.6 ± 46 vs. 384.4 ± 69 vs. 405 ± 27.4 µg/ml). In logistic regression analysis, pretransplant fetuin-A levels did not correlate with graft failure after 3 years' follow-up (p = 0.895). In COX regression analysis, fetuin-A levels were not associated with the time to graft loss. Moreover, fetuin-A levels correlated neither with renal and metabolic parameters nor with cellular or humoral rejection episodes. CONCLUSION: Pretransplant levels of fetuin-A are not a predictor for renal allograft loss or rejection episodes after 36 months' follow-up in transplant recipients.

Combined transplantation of pancreatic islets and adipose tissue-derived stem cells enhances the survival and insulin function of islet grafts in diabetic mice.

BACKGROUND: Overcoming significant loss of transplanted islet mass is important for successful islet transplantation. Adipose tissue-derived stem cells (ADSCs) seem to have angiogenic potential and antiinflammatory properties. We hypothesized that the inclusion of ADSCs with islet transplantation should enhance the survival and insulin function of the islet graft. METHODS: Syngeneic ADSCs and allogeneic islets were transplanted simultaneously under the kidney capsules of diabetic C57BL/6J mice. Rejection of the graft was examined by measurement of blood glucose level. Revascularization and inflammatory cell infiltration were examined by immunohistochemistry. RESULTS: Transplantation of 400 islets only achieved normoglycemia with graft survival of 13.6±1.67 days (mean±standard deviation), whereas that of 100 or 200 allogeneic islets never reversed diabetes. Transplantation of 200 islets with 2×10(5) ADSCs reversed diabetes and significantly prolonged graft survival (13.0±5.48 days). Results of glucose tolerance tests performed on day 7 were significantly better in islets-ADSCs than islets-alone recipients. Immunohistochemical analysis confirmed the presence of insulin-stained islet grafts with well-preserved structure in islets-ADSCs transplant group. Significant revascularization (larger number of von Willebrand factor-positive cells) and marked inhibition of inflammatory cell infiltration, including CD4+ and CD8+ T cells and macrophages, were noted in the islets-ADSCs transplant group than islets-alone transplant group. CONCLUSIONS: Our results indicated that cotransplantation of ADSCs with islet graft promoted survival and insulin function of the graft and reduced the islet mass required for reversal of diabetes. This innovative protocol may allow "one donor to one recipient" islet transplantation.

Clinical evidence of the association between serum perioperative changes in xanthine metabolizing enzymes activity and early post-transplant kidney allograft function.

BACKGROUND: Xanthine oxidoreductase (XOR) and its active forms, dehydrogenase (XD) and oxidase (XO), act as double-edged swords during ischemia-reperfusion injury. On the one hand, their action generates antioxidants, such as uric acid (UA); however, they may strongly enhance production of free radicals. In this study, we examined the association between post-transplant graft function and perioperative xanthine metabolizing enzymes (XME) activity in kidney transplant recipients divided into early (EGF), slow (SGF), and delayed graft function (DGF) groups. STUDY DESIGN: XME activity and UA levels were measured in blood samples collected directly before and during the first and fifth minutes of reperfusion. RESULTS: Results demonstrated an increase in XO and XOR activity in all groups; however, these parameters were lower in the EGF than in the DGF group (p < 0.005; p < 0.05). XD activity increased in SGF and DGF patients (p = 0.01); nevertheless, the XD/total XOR coefficient decreased only in DGF individuals (p = 0.0007). XME sensitivity, specificity, and positive and negative predictive values in discriminating SGF/DGF from EGF were 73.3% to 78%, 54% to 62.5%, 76% to 78.6%, and 56.5%, respectively. Moreover, mixed model analysis revealed that recipients classified according to results of XOR(5) and XO(5) significantly differ in 1-year post-transplant allograft function (p = 0.04 and p = 0.02, respectively), but not in the frequency of acute rejection episodes (p = 0.66 and p = 0.90, respectively). CONCLUSIONS: During renal transplantation, significant changes in XME occur that are associated with early post-transplant graft function and have potential value to discern between EGF and SGF/DGF.

Association between the heme oxygenase-1 promoter polymorphism and renal transplantation outcome in Greece.

BACKGROUND: Heme oxygenase-1 (HO-1) is the enzyme that catabolizes heme into carbon monoxide, biliverdin, and free iron. The induction of this enzyme is an important cytoprotective mechanism, which occurs as an adaptive and beneficial response to a wide variety of oxidant stimuli. HO-1 has recently been suggested to protect transplants from ischemia/reperfusion and immunologic injury. HO-1 inducibility is mainly modulated by a (GT)(n) repeat polymorphism in the promoter region, and has been shown that short repeats (S) are associated with greater upregulation of HO-1, compared with long repeats (L). In the present study we investigated the influence of this HO-1 gene polymorphism on clinical outcome after transplantation and on renal transplant function. METHODS: DNA from 175 donor/recipient pairs who underwent transplantation between October 2002 and June 2007 was genotyped. We divided the HO-1 alleles into 2 subclasses, the S ≤ 27 repeats and L > 27 repeats. RESULTS: There has been significant relevance between the genotype of the donor and the outcome of the graft, as far as recipients with normal graft function and recipients with deteriorated graft function are concerned (P = .021). In patients with normal graft function, grafts from L-homozygotes were found in 24%, whereas in patients with deteriorated function, grafts from L-homozygotes exhibited in higher rate (50%). Neither the donor's nor the recipient's polymorphism influenced the graft survival (log-rank test P = .228 for the donors and log-rank test P = 0.844 for the recipients). There was no evidence of a gene-dose effect on graft survival (P = .469). Recipients of allografts from S-carriers donors had significantly lower serum creatinine levels at 24 months compared with recipients of allografts from L-homozygotes donors (P = .016).

Effect of pyruvate and HEPES on rat lung allograft acidosis and cell death after long-term hypothermic storage.

BACKGROUND: We have previously demonstrated that adding pyruvate to Perfadex increased graft metabolism during 24-hour storage and improved reperfusion lung function. This increased metabolism was associated with progressively lower pH of the storage solution during the preservation interval. OBJECTIVE: To determine whether more effective pH regulation would result in further improvements in lung survival after hypothermic storage. MATERIALS AND METHODS: Rat lungs were stored for 24 hours in Perfadex, Perfadex with HEPES (N-2-hydroxyethylpiperazine-propanesulfonic acid) buffer, pyruvate-modified Perfadex, and pyruvate-modified Perfadex with HEPES. Change in pH in the storage solution was measured. Structural lung injury was evaluated using hematoxylin-eosin stained tissue sections. Cell death was quantified by measuring necrotic cells using trypan blue exclusion and apoptotic cells via the TUNEL (terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate nick-end labeling) assay. RESULTS: Lungs stored in Perfadex demonstrated the greatest degree of cell death. Lungs in the Pyruvate group exhibited decreased cell death despite greater acidosis. The addition of HEPES reduced cell death and preservation solution acidosis in both Perfadex and pyruvate-modified Perfadex (P < .05). Almost all cell death resulted from necrosis. Adding pyruvate to the preservation solution increases acid formation during storage, but decreases cell death. HEPES ameliorates this acidosis and decreases allograft cell destruction. CONCLUSION: Increasing the preservation solution buffering capacity may be a simple strategy for improving lung preservation for transplantation.

Effect of triple costimulation blockade on islet allograft survival in sensitized mice.

BACKGROUND: Islet allograft rejection in sensitized recipients is difficult to control by costimulation blockade using anti-CD154 and cytotoxic T-lymphocyte antigen-4 immunoglobulin (CTLA4Ig). Because leukocyte function antigen (LFA) 1 is highly expressed on memory T cells, adding an LFA-1 blockade may inhibit memory T-cell activities. We examined the effects on islet allograft survival of triple costimulation blockade in presensitized recipient mice. METHODS: C57BL/6 mice were sensitized by transplantation under the kidney capsule or intraperitoneal injection of Balb/c islets. Four weeks after transplantation, sensitization was confirmed by flow-cytometric detection of alloreactive antibodies. Diabetes was induced by a single intravenous injection of streptozotocin. Recipients were transplanted with 200 Balb/c islets under the right kidney capsule. Graft function was assessed by daily blood glucose and body weight records. Transplanted animals were divided into 3 treatment groups: group 1, control antibody; group 2, anti-CD154 and CTLA-4 Ig double therapy; group 3, anti-CD154, CTLA4Ig, and anti-LFA-1 triple therapy. Injections were administered every second day from day -2 to day 8. RESULTS: Naïve mice rejected islet allografts between days 7 and 29 (mean 16 +/- 6 d; n = 5), sensitized mice in group 1 between days 0 and 14 (mean 7 +/- 5 d; n = 8), in group 2 between days 4 and 16 (mean 8 +/- 4 d; n = 7), and in group 3 between days 4 and 26 (mean 11 +/- 7 d; n = 10). CONCLUSION: Triple costimulation blockade with anti-CD154, CTLA4Ig, and anti-LFA-1 was not sufficient to improve islet allograft survival in sensitized recipients.

In renal transplants with delayed graft function chemokines and chemokine receptor expression predict long-term allograft function.

BACKGROUND: Chronic loss of renal allograft function is associated with interstitial fibrosis and tubular atrophy (IF/TA). Independent of the underlying reason, one initial step in the development of fibrosis is chemokine-driven invasion of leukocytes from the blood vessels into the allograft. We studied the role of chemokines in kidney allografts with delayed graft function and the subsequent long-term outcome of renal function and fibrosis. METHODS: We examined repetitive biopsies of 30 patients without signs of acute rejection but with initially delayed graft function for IF/TA. In addition, we examined the expression of chemokine receptor (CCR)-1 and CCR2 on invaded leukocytes and macrophages and the corresponding ligands regulated upon activation, normal t-cell expressed, and secreted (RANTES) and monocyte chemotactic protein-1 on residential kidney cells. RESULTS: The initial expression of CCR1 positive invading cells and RANTES in glomerular cells correlated with the allograft function 12 months after transplantation and at last follow-up. The expression was independent of donor characteristics such as age, gender, infectious state, cause of death, or use of vasopressive agents. Furthermore, it did not correlate with the duration of cold ischemia time. Among the patients with the most progressive loss of allograft function follow-up biopsy specimen did not reveal any signs of rejection but showed increased CCR1 and RANTES expression in the interstitium suggesting ongoing inflammation and fibrosis. CONCLUSION: An early expression of RANTES in renal allografts with delayed graft function with consecutive invasion of CCR1 positive cells seems to promote ongoing IF/TA and to worse renal allograft outcome.

Outcomes of simultaneous liver/kidney transplants are equivalent to kidney transplant alone: a preliminary report.

BACKGROUND: With adoption of Model for End-Stage Liver Disease, the number of simultaneous liver-kidney transplants (SLK) has greatly increased. A recent registry study questioned the equity of allocating kidney transplants (KTx) simultaneously with liver transplantation due to poor outcomes (Locke et al., Transplantation 2008; 85: 935). METHODS: To investigate outcome of KTx in SLK, all SLK (n=36) performed at our center from January 2000 to December 2007 were reviewed and KTx outcomes compared with those of kidney transplant alone (KTA) performed during that period (n=1283). We also reviewed whether pretransplant panel reactive antibody and donor-specific antibody affected KTx outcome in SLK. RESULTS: One- and 3-year KTx and patient survival were not different between KTA and SLK regardless of sensitization level. There were 348 (27%) KTx failures in KTA vs. 6 (17%) in SLK (NS). Overall freedom from acute cellular rejection (ACR) and antibody-mediated rejection (AMR) in SLK was 93 and 96% at 3 years, compared with 72 and 78% in KTA (P=0.0105 and P=0.0744, respectively). Sensitized KTx recipients had more ACR and AMR (32 and 38%) at 3 years compared with nonsensitized recipients (28 and 20%) (P=0.23 and 0.0001, respectively). No differences in ACR and AMR were observed when SLK was divided and level of sensitization compared (P=0.17 and 0.65, respectively). CONCLUSION: SLK is a life-saving procedure with excellent patient and graft survival. AMR incidence in the KTx appears reduced in SLK compared with KTA regardless of level of preoperative panel reactive antibody. A high level of donor-specific antibody should not preclude simultaneous transplantation when clinically indicated.

Deceased donor management and demographic factors related to kidney allograft rejection and graft survival.

BACKGROUND: There is agreement that the number of organ donors and the number of organs recovered per donor are not maximized despite promotion of awareness and new guidelines for transplant teams. A single standard for donor management does not exist, in part because there is no consensus with respect to donor factors and management effect on transplant outcomes. METHODS: This retrospective study analyzed the long-term outcomes of 402 deceased donor kidney transplant recipients with respect to donor factors. This study differed from previous studies in that all recipients were treated with the same selection and immunosuppressive protocols. RESULTS: Factors associated with improved graft survival included cause of death, more organs donated, and lower peak sodium (P < .01). Delayed graft function (DGF) decreased if more organs were donated, but increased when the donor was given dopamine. Recipients of donor kidneys with higher final creatinine values were more likely to show DGF (P < .01). A decrease in acute rejection episodes was observed among patients whose donors had received dopamine, donated more organs, and had a shorter time between incision and cross clamp (P < .05). Kidneys from donors with a higher final creatinine displayed fewer rejection episodes; those with a higher peak creatinine experienced more rejection episodes (P < .05). CONCLUSION: The effect of donor variables on kidney transplant outcomes is important and may not be consistent with traditional expectations. Additional data collection and assessment of both short- and long-term transplant outcomes are critical to improve our understanding of the impact of deceased donor factors and management.

Cell apoptosis and Fas gene expression in liver and renal tissues after ischemia-reperfusion injury in liver transplantation.

Ischemia-reperfusion (I/R) injury is an important factor in a nonfunctioning liver graft and acute renal failure. Apoptosis is a cell death mechanism in early stages of I/R injury. In the present study, orthotopic liver transplantation (oLT) using a modified double-cuff method was performed in Wistar rats, with sham-operated rats serving as the control group. Rats in the treatment and control groups were sacrificed at 1, 3, 6, 12, and 24 hours after oLT to obtain liver and kidney tissues. Fas protein expression in apoptotic cells at various times was detected at immunohistochemical staining and flow cytometry, and Fas gene expression was detected using the reverse transcriptase polymerase chain reaction. Apoptosis began in liver and renal cells at 1 hour after oLT, peaking at 12 hours. The reverse transcriptase polymerase chain reaction demonstrated Fas gene expression in liver and renal tissues at 1 hour post-oLT, peaking at 12 hours. Changes in the treatment group were significantly greater than in the control group (P < .05). We conclude that renal cells, like liver cells, undergo apoptosis due to I/R injury after oLT.

Suppression of nuclear factor-kappaB activity in Kupffer cells protects rat liver graft from ischemia-reperfusion injury.

OBJECTIVE: The objective of this study was to investigate the protective effect and mechanisms of nuclear factor (NF)-kappaB decoy oligodeoxynucleotides (ODN) on rat liver grafts following ischemia-reperfusion injury (IRI). METHODS: Animals were randomly divided into 3 groups (n = 8): control ischemia-reperfusion (IR) and decoy ODN groups; in the last cohort donor grafts were transfected with 120 microg NF-kappaB decoy ODN before procurement. Following 2 hours of reperfusion, NF-kappaB binding activity was detected in isolated Kupffer cells (KCs) using electrophoretic mobility shift assays (EMSA). Tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 messenger RNA (mRNA) expressions were analyzed using reverse transcriptase polymerase chain reaction (RT-PCR) methods. Liver tissue and blood serum were collected for histopathologic examination and liver function test, respectively. RESULTS: The NF-kappaB binding activity, TNF-alpha and IL-6 mRNA expression as well as serum ALT and total bilirubin levels were significantly increased compared with the control group following reperfusion (P < .01). A large number of hepatocytes showed degeneration and necrosis. However, these indices were significantly ameliorated among the decoy ODN group (P < .01) with preserved hepatic lobule architecture. CONCLUSION: KCs NF-kappaB activation following reperfusion plays an important role in IRI after liver transplantation. The decoy strategy showed an apparent effect to suppress NF-kappaB activation and inhibit production of downstream cytokines, thereby protecting liver grafts from IRI.

Urinary connective tissue growth factor is a biomarker in a rat model of chronic nephropathy.

AIM: This study sought to determine whether urinary connective tissue growth factor (CTGF) was a molecular marker for chronic allograft nephropathy (CAN). METHODS: F344 rat renal grafts orthotopically transplanted into Lewis rats following the procedure of Kamada were harvested at 4,8,12, or 16 weeks. Morphological changes were studied using hematoxylin eosin (HE) and Masson trichrome stains. Serum creatinine (SCr) was measured. CAN grades were evaluated according to the Banff97 schema. Expressions of CTGF in the kidney and urine were determined using real-time polymerase chain reaction (PCR) Western blots, and competitive indirect enzyme-linked immunosorbent assay (ELISA). Spearman correlation analysis was used to compare urinary CTGF expression and CAN development. RESULTS: SCr levels and Banff scores increased in a time-dependent manner. The expression of CTGF in the graft was markedly elevated compared with the control group. Urine CTGF increased by week 4, and maintained high levels up to week 16. The urinary levels correlated positively with the histological presence of CAN. Thus, urine CTGF concentrations reflected the course of CAN, especially at an early stage. CONCLUSION: CTGF plays a significant role in the pathological changes of CAN after kidney transplantation. Urinary CTGF has the potential to be a biomarker for CAN.

The changes of aquaporin 2 in the graft of acute rejection rat renal transplantation model.

AIM: To investigate the significance and changes of Aquaporin 2 (AQP2) in the rat renal graft of acute rejection (AR). METHODS: Wistar recipients of Spraque-Dawley or Wistar renal grafts were treated with cyclosporine (CsA). Renal grafts were harvested at various times after transplantation for analysis of the levels of AQP2 mRNA and protein of by RT-PCR and immunohistochemistry. RESULTS: The expression of AQP2 mRNA and protein in the acutely rejecting were grafts significantly decreased (P < 0.05) compared with the control group. But the expression of AQP2 mRNA and protein in the syngeneic grafts (sTX) versus the immunosuppression group (aTX+CsA) showed no difference compared with a control group (P > 0.05). Furthermore, at day 5 and day 7 after transplantation the expressions of AQP2 expression in the allogeneic group (aTX) were decreased significantly compared with day 3 after transplantation (P < 0.05). In addition, there was no remarkable difference at day 5 or 7 after transplantation. CONCLUSION: AQP2 mRNA and protein expressions were down-regulated during renal transplant acute rejection, which had no relationship to the ischemia reperfusion injury and denervation damage. Furthermore, CsA administration after kidney transplantation blunted this down-regulation (P > 0.05).

All-trans retinoic acid attenuates cardiac allograft vasculopathy in rats.

OBJECTIVE: We sought to study the inhibitory effects of all-trans retinoic acid (ATRA) on cardiac allograft vasculopathy in rats. METHODS: Inbred Wistar and Sprague-Dawley rats were used as donors and recipients, respectively. After abdominal heterotopic heart transplantation, animals were randomized to a cyclosporine (CsA) group versus a CsA+ATRA group: 10 mg/kg/d CsA versus the same CsA dose plus 10 mg/kg/d ATRA. Transplanted hearts were analyzed at 60 days. Cardiac allograft sections were treated with Van Giesson stain to examine vascular luminal occlusion, with immunohistochemistry for CD68 and proliferating cell nuclear antigen (PCNA), and with reverse-transcription polymerase chain reaction (RT-PCR) for platelet-derived growth factor A (PDGF-A) mRNA. RESULTS: Luminal occlusion in the CsA+ATRA group was significantly less than that in the CsA group (40.10 +/- 8.20% vs 62.86 +/- 17.18%; P < .01). The CsA+ATRA group showed a marked reduction in PCNA- and CD68-positive cells: namely, 33.96 +/- 8.65% versus 60.17 +/- 17.74% (P < .01) and 17.63 +/- 4.24% versus 32.13 +/- 9.26 (P < .01), respectively. RT-PCR analysis showed that relative PDGF-A mRNA content in the CsA+ATRA group was significantly decreased compared with the CsA group (0.46 +/- 0.08 vs 0.94 +/- 0.11; P < .01). CONCLUSION: ATRA may attenuate rat cardiac allograft vasculopathy by inhibiting macrophage infiltration and cell proliferation.

Prolonged cardiac allograft survival using iodine 131 after human sodium iodide symporter gene transfer in a rat model.

BACKGROUND: Radioiodine is efficiently concentrated by tissues expressing the human sodium iodide symporter (hNIS). OBJECTIVE: To analyze the effects of iodine 131 on acute cardiac allograft rejection after ex vivo hNIS gene transfer in a rat model of cardiac allotransplantation. MATERIALS AND METHODS: Hearts from Brown Norway rats were perfused ex vivo either with UW (University of Wisconsin) solution (n = 9) or UW solution containing 1 x 10(9) pfu/mL of adenovirus 5 plus NIS (Ad-NIS) (n = 18). Donor hearts were transplanted heterotopically into the abdomen of Lewis rats, and recipients were treated on postoperative day 3 with either 15,000 microCi of (131)I or saline solution. The hearts were explanted when no longer beating, and were evaluated histologically for evidence of rejection and other changes. RESULTS: Grafts perfused with the Ad-NIS vector survived significantly longer in recipients injected with (131)I (mean [SD], 11.3 [1.9] days) compared with control animals not treated with (131)I (5.7 [0.65] days) (P < .001). Treatment with (131)I did not prolong graft survival in recipients of hearts that were not perfused with Ad-NIS (5.5 [1.0] vs 5.3 [0.8] days). In Ad-NIS (131)I-treated transplants, the level of myocardial damage on day 6 after surgery, when control hearts were rejected, was significantly lower (60.8 [28.0] vs 99.7 [0.8]; P < .05). CONCLUSION: Our findings indicate that (131)I, after NIS gene transfer, can effectively prolong cardiac allograft survival. To our knowledge, this is the first report of the use of NIS-targeted (131)I therapy in cardiac transplantation. Further studies are required to determine the mechanism of this effect and its potential for clinical application.