Intragraft FOXP3 mRNA expression reflects antidonor immune reactivity in cardiac allograft patients

BACKGROUND: Regulatory FOXP3+ T cells control immune responses of effector T cells. However, whether these cells regulate antidonor responses in the graft of cardiac allograft patients is unknown. Therefore, we analyzed the gene expression profiles of regulatory and effector T-cell markers during immunological quiescence and acute rejection. METHODS: Quantitative real-time polymerase chain reaction was used to analyze mRNA expression levels in time-zero specimens (n=24) and endomyocardial biopsies (EMB; n=72) of cardiac allograft patients who remained free from rejection (nonrejectors; n=12) and patients with at least one histologically proven acute rejection episode (rejectors; International Society for Heart and Lung Transplantation [ISHLT] rejection grade>2; n=12). RESULTS: For all analyzed regulatory and effector T-cell markers, mRNA expression levels were increased in biopsies taken after heart transplantation compared with those in time-zero specimens. Posttransplantation, the FOXP3 mRNA levels were higher in EMB assigned to a higher ISHLT rejection grade than the biopsies with grade 0: the highest mRNA levels were detected in the rejection biopsies (rejection grade>2; P=0.003). In addition, the mRNA levels of CD25, glucocorticoid-induced TNF receptor family-related gene, cytotoxic T lymphocyte-associated antigen 4, interleukin-2, and granzyme B were also significantly higher in rejecting EMB than in nonrejecting EMB (rejection grade相似文献   

FOXP3 mRNA expression analysis in the peripheral blood and allograft of heart transplant patients

Previously, we demonstrated in heart transplant patients that FOXP3, a gene required for the development and function of regulatory T cells, was highly expressed in the graft during an acute cellular rejection. In this study, we analyzed whether the FOXP3 gene expression in the peripheral blood also reflects anti-donor immune responses, and therefore may provide clues for non-invasive detection of non-responsiveness or acute rejection. We examined the FOXP3 expression patterns of peripheral blood mononuclear cells (PBMC; n=69) of 19 heart transplant patients during quiescence and rejection in comparison with those of endomyocardial biopsies (EMB; n=75) of 24 heart transplant patients. While the FOXP3 mRNA levels were abundantly expressed in rejecting EMB (ISHLT rejection grade>1R) compared with EMB without histological evidence of myocardial damage (ISHLT rejection grade 0R-1R; p=0.003), no association with rejection or non-responsiveness was found for the FOXP3 mRNA levels in the peripheral blood. Thus, in contrast to intragraft FOXP3 gene expression, the peripheral FOXP3 mRNA levels lack correlation with anti-donor immune responses in the graft, and, consequently, FOXP3 does not appear to be a potential candidate gene for non-invasive diagnosis of non-responsiveness or rejection.     

Th‐17 Alloimmune Responses in Renal Allograft Biopsies From Recipients of Kidney Transplants Using Extended Criteria Donors During Acute T Cell–Mediated Rejection

Although renal transplantation using expanded criteria donors has become a common practice, immune responses related to immunosenescence in those kidney allografts have not been studied yet in humans. We performed a retrospective molecular analysis of the T cell immune response in 43 kidney biopsies from patients with acute T cell–mediated rejection including 25 from recipients engrafted with a kidney from expanded criteria donor and 18 from recipients grafted with optimal kidney allograft. The clinical, transplant and acute T cell–mediated rejection characteristics of both groups were similar at baseline. The expression of RORγt, Il‐17 and T‐bet mRNA was significantly higher in the elderly than in the optimal group (p = 0.02, p = 0.036, and p = 0.01, respectively). Foxp3 mRNA levels were significantly higher in elderly patients experiencing successful acute T cell–mediated rejection reversal (p = 0.03). The presence of IL‐17 mRNA was strongly associated with nonsuccessful reversal in elderly patients (p = 0.008). Patients with mRNA IL17 expression detection and low mRNA Foxp3 expression experienced significantly more treatment failure (87.5%) than patients with no mRNA IL17 expression and/or high mRNA Foxp3 expression (26.7%; p = 0.017). Our study suggests that the Th17 pathway is involved in pathogenesis and prognosis of acute T cell–mediated rejection in recipients of expanded criteria allograft.     

Acute vascular rejection is associated with systemic complement activation in a pig-to-primate kidney xenograft model

The introduction of h-DAF transgenic porcine organs into pre-clinical pig-to-primate discordant xenotransplantation has led to complete and reliable abrogation of hyperacute xenograft rejection (HAR). Despite additional heavy immunosuppression however, most xenografts are still lost due to acute vascular rejection (AVR), with current treatment protocols being of only limited value. In a life-supporting model of pig-to-primate kidney transplantation, unmodified (n=8) or h-DAF-transgenic (n=9) porcine kidneys were transplanted into cynomolgus monkeys under cyclophosphamide (CyP), cyclosporine and low-dose steroid immunosuppression. Longest recipient survival was 11 days in the control group and 68 days in the h-DAF transgenic group. Stable initial graft function with recipient survival >4 days was generated in eight animals (two controls and six transgenics). In these animals, plasma complement levels were analyzed during ongoing AVR. Compared with baseline levels, a two-fold increase in C3a levels and a four-fold increase in sC5b-9 levels were measured. In parallel to systemic complement activation, increased deposition of C3 and C5b-9 along with massive staining for recipient IgM immunoglobulins was detected in the xenografts on immunohistochemistry. We conclude that acute vascular xenograft rejection of porcine kidneys in cynomolgus monkeys is associated with classical pathway complement activation following binding of induced recipient anti-porcine antibodies. This complement activation can be observed despite membrane bound expression of human complement regulators in the porcine xenografts. Therefore, additional short-term fluid phase complement inhibition seems necessary for the future development of protocols designed for treatment of AVR in the pig-to-primate combination.     

Acute vascular rejection is associated with up-regulation of vitronectin receptor (alphavbeta3), increased expression of tissue factor, and activation of the extracellular matrix metalloproteinase induction system.

BACKGROUND: A cascade of inflammatory reactions characterize acute vascular rejection after heart transplantation. This study was undertaken to test the hypothesis that acute vascular rejection is associated with up-regulation of vitronectin receptor (alphavbeta3), increased expression of tissue factor, and activation of the extracellular matrix metalloproteinase induction system. METHODS: Acute vascular rejection developed in 14 heart transplant recipients within 2 weeks of transplantation, confirmed by immunofluorescence (AVR group). We compared these patients with 10 transplant recipients who had no evidence of acute vascular rejection or peritransplant ischemic injury (control group). We evaluated endomyocardial biopsy specimens for alphavbeta3, tissue factor, and extracellular matrix metalloproteinase inducer (EMMPRIN). RESULTS: Compared with the control group, the AVR group demonstrated evidence of significantly increased expression of alphavbeta3 (1.9-fold, p < 0.001), tissue factor (1.8-fold, p < 0.001), and EMMPRIN (1.5-fold, p < 0.001). All patients in the AVR group received plasmapheresis; 11 of 14 patients had evidence of ischemic necrosis on biopsy specimens, and 3 of 14 patients experienced hemodynamic compromise and graft dysfunction and died within 3 weeks of transplant. Another patient died at 10 months after transplant. CONCLUSIONS: Acute vascular rejection is associated with up-regulation of alphavbeta3, tissue factor, and activation of the matrix metalloproteinase induction system, which may contribute to the lethal morbidity associated with this disease.     

Isolated v‐lesion represents a benign phenotype of vascular rejection of the kidney allograft – a retrospective study

While the detrimental impact of the humoral acute vascular rejection (AVR) phenotype is recognized, the prognostic significance of isolated v‐lesion (IV) remains unclear. In this retrospective single‐centre study, AVR was found in 98 of 1015 patients (9.7%) who had undergone kidney transplantation in 2010–2014, with donor‐specific antibodies (DSA) evaluated in all of them. The outcome of four AVR phenotypes was evaluated during median follow‐up of 59 months; in 25 patients with IV, 18 with T‐cell‐mediated vascular rejection (TCMVR), 19 with antibody‐mediated vascular rejection (AMVR) and 36 with suspected antibody‐mediated rejection (sAMVR). AVR was diagnosed mainly by for‐cause biopsy (81%) early after transplantation (median 19 POD) and appeared as mild‐grade intimal arteritis. IV occurred in low‐sensitized patients after the first transplantation (96%) in the absence of DSA. IV responded satisfactorily to treatment (88%), showed no persistence of rejection in surveillance biopsy, and had stable graft function, minimal proteinuria and excellent DCGS (96%). Contrary to that, Kaplan–Meier estimate of 3‐year DCGS of AMVR was 66% (log‐rank = 0.0004). Early IV represents a benign phenotype of AVR with a favourable outcome. This study prompts further research to evaluate the nature of IV before considering any change in the classification and management.     

Evaluation of posttransplantation soluble CD30 for diagnosis of acute renal allograft rejection

BACKGROUND: Posttransplantation measurement of soluble CD30 (sCD30) may be useful for identifying kidney graft recipients at risk of impending graft rejection in the early posttransplantation period. METHODS: We measured plasma sCD30 levels and evaluated the levels in relation to the diagnosis of rejection. RESULTS: Receiver operating characteristic curves demonstrated that on posttransplantation days 3 to 5, sCD30 allowed a differentiation of recipients who subsequently developed acute allograft rejection (n=25) from recipients with an uncomplicated course (n=20, P<0.0001) (area under the receiver operating characteristic curve 0.96, specificity 100%, sensitivity 88%) and recipients with acute tubular necrosis in the absence of rejection (n=11, P=0.001) (area under the receiver operating characteristic curve 0.85, specificity 91%, sensitivity 72%). CONCLUSIONS: sCD30 measured on posttransplantation days 3 to 5 offers a noninvasive means for differentiating patients with impending acute allograft rejection from patients with an uncomplicated course or with acute tubular necrosis.     

FoxP3+ T cells can be expanded from rejecting cardiac allografts

A specific subset of T cells, the FoxP3+ regulatory T cells, control effector T-cell responses to self and foreign antigens. In transplant patients, we and others have shown that high intragraft FOXP3 mRNA levels are associated with acute rejection, suggesting that immune regulation is dependent on immune activation. To study whether transplanted grafts harbor FoxP3+ T cells and to functionally analyze them, graft infiltrating lymphocytes (GILs) must be propagated from the transplanted tissue. In the present study, we analyzed whether FoxP3+ T cells can be grown from endomyocardial biopsies (EMBs; n = 5) from patients after heart transplantation during acute cellular rejection. After 18 to 21 days of culture, 0.5 to 1.0 x 10(6) GILs were cultured from the EMBs. Of these GILs, 10.6% (median; range, 1.6%-17.1%) stained positive for FoxP3. Thus Foxp3+ T cells can be grown from EMBs, providing the tools to functionally characterize these cells in depth in forthcoming studies.     

Clinical and pathological assessment of acute vascular rejection in the transplant kidney

Koike J, Yamaguchi Y, Horita S, Tanabe K, Fuchinoue S, Toma H, Nihei H. Clinical and pathological assessment of acute vascular rejection in the transplant kidney. Clin Transplantation 2001: 15 (Supplement 5): 41–44. ©Munksgaard, 2001
Acute vascular rejection (AVR) in kidney transplan- tation is the most important factor influencing graft prognosis. We focus on patients whose grafts were lost because of AVR, and assessed their clinical characteristics and histological findings of biopsied renal grafts. Biopsied specimens exhibited AVR in 43 patients who underwent kidney transplantation in the Kidney Center of Tokyo Women's Medical University from 1995 to 1999. In the follow-up from 1 to 5 yr (median: 2.5 yr) we classified these patients into three groups: favourable prog- nosis group (FPG), relatively poor prognosis group (RPPG) and poor prognosis group (PPG). Light microscopic study for histological grading of acute rejection according to the Banff scheme and detection of the C4d complement deposition on peritubular capillaries by the immunofluorescence method were performed. Based on the results, the donors of RPPG and PPG were significantly older than those of FPG, and all factors of acute rejection according to the Banff scheme were not statistically significantly different among the three groups. However, an acute tubular injury mimicking acute tubular necrosis (ATN) was observed in the biopsy specimens from PPG. In conclusion, an older donor is a risk factor of poor prognosis of the graft with AVR, and acute tubular injury mimicking ATN is one of the important features that enables the prediction of graft failure originating from AVR in kidney transplantation.     

Banff criteria as predictors of outcome following acute renal allograft rejection.

BACKGROUND: The Banff classification of renal allograft rejection grades acute tubulointerstitial rejection (AIR) by severity of tubulitis and acute vascular rejection (AVR) by severity of arteritis. The intensity of tubulitis has not, however, been demonstrated to be of prognostic value and other features such as glomerulitis and eosinophil infiltration are of uncertain significance. This study was performed in order to determine the clinical value of this pathological classification. METHODS: Banff criteria were correlated with outcome in 134 consecutive graft recipients transplanted in our unit over a 3-year period (1994 1996) who experienced at least one biopsy-confirmed acute rejection episode. Of 197 biopsies performed for the diagnosis of rejection, 177 contained at least one artery and were suitable for Banff grading. Tissue eosinophil counts were available for 101 biopsies. Clinical severity of rejection was classified as mild (fully responsive to pulse steroid therapy), moderate (partially steroid responsive) and severe (steroid unresponsive/requiring ATG therapy). RESULTS: Graft failure ensued in 18 of 58 patients with AVR compared with 10 of 65 patients with AIR (P= < 0.05). Clinical severity of rejection correlated with the presence of arteritis, but not severity of tubulitis; rejections graded I, IIA and IIB according to the Banff' 93 classification were clinically severe in 3/68 (4%), 2/28 (7%) and 15/67 (22%) respectively (P= <0.05). The presence of glomerulitis showed no correlation with clinical severity or graft loss. Tissue eosinophilia (>10 eosinophils/mm2) was present in 18 of 33 patients who had at least one episode of AVR (v1/2), compared with 11 of 45 patients who suffered only AIR (P= <0.02). CONCLUSIONS: We conclude that: arteritis, but not severe tubulitis or glomerulitis, is an adverse prognostic factor in acute rejection and that tissue eosinophilia is associated with vascular rejection. Our findings support the 1997 revision of the Banff classification, replacing grades with types of acute rejection.     

The regulatory/cytotoxic graft-infiltrating T cells differentiate renal allograft borderline change from acute rejection

The interpretation of cellular infiltrate from renal transplant recipients with borderline (BL) changes is still a challenging problem. To analyze the immune phenotype of such infiltrate, we quantified the mRNA expression of Foxp3 and interleukinL-10 and granzyme B (GB) in 15 kidney biopsies with BL changes. Controls were patients presenting type IA acute rejection and nonrejecting patients. Only levels of GB mRNA correlated significantly with response to antirejection therapy. Levels of Foxp3 mRNA in BL changes were intermediate between type IA acute rejection and nonrejecting controls. To determine the balance of alloagressive to graft-protecting T cells, we quantified the Foxp3/GB ratio. BL changes T cells infiltrate expressed a significantly higher Foxp3/GB ratio than that in IA acute rejection. These results suggest that T cell infiltrate from BL change exhibit a tolerogenic rather than a cytotoxic phenotype.     

Expression of the chemokine receptor CXCR3 in human renal allografts--a prospective study.

BACKGROUND: Mechanisms involved in the recruitment and activation of inflammatory cells during renal allograft injury are still incompletely understood. Since chemokines play pivotal roles in this process, our prospective study was performed to evaluate further the role of the chemokine receptor CXCR3. METHODS: A total of 138 biopsies were included from patients without rejection and unaltered morphology (according to Banff 97 classification grade 1, n = 49), with acute interstitial rejection (Banff grade 4 type I, n = 8), with acute vascular rejection (Banff grade 4 type II, n = 23), with chronic allograft nephropathy (Banff grade 5, n = 16), without rejection but with various other lesions (Banff grade 6, n = 36) and from pre-transplant kidneys (n = 6). The expression of CXCR3-, CD4- and CD8-positive cells was localized by immunohistochemistry and quantified by image analysis. RESULTS: CXCR3 was expressed by infiltrating inflammatory cells, but not by intrinsic renal structures. CXCR3-positive cells were found to be involved in tubulitis and vascular rejection. The area of CXCR3-positive staining was significantly larger in biopsies with acute interstitial rejection (P<0.001) and acute vascular rejection (P<0.001) as compared with normal renal graft biopsies. There was a strong morphological and numerical correlation between CXCR3 and both CD4- and CD8-positive T cells, respectively. CONCLUSIONS: A significant part of both CD4- and CD8-positive T cells express the chemokine receptor CXCR3. During renal allograft rejection, the number of these cells increases significantly at the site of injury and might be targeted by CXCR3 blocking agents.     

Urinary Cell mRNA Profiles and Differential Diagnosis of Acute Kidney Graft Dysfunction

Noninvasive tests to differentiate the basis for acute dysfunction of the kidney allograft are preferable to invasive allograft biopsies. We measured absolute levels of 26 prespecified mRNAs in urine samples collected from kidney graft recipients at the time of for-cause biopsy for acute allograft dysfunction and investigated whether differential diagnosis of acute graft dysfunction is feasible using urinary cell mRNA profiles. We profiled 52 urine samples from 52 patients with biopsy specimens indicating acute rejection (26 acute T cell–mediated rejection and 26 acute antibody-mediated rejection) and 32 urine samples from 32 patients with acute tubular injury without acute rejection. A stepwise quadratic discriminant analysis of mRNA measures identified a linear combination of mRNAs for CD3ε, CD105, TLR4, CD14, complement factor B, and vimentin that distinguishes acute rejection from acute tubular injury; 10-fold cross-validation of the six-gene signature yielded an estimate of the area under the curve of 0.92 (95% confidence interval, 0.86 to 0.98). In a decision analysis, the six-gene signature yielded the highest net benefit across a range of reasonable threshold probabilities for biopsy. Next, among patients diagnosed with acute rejection, a similar statistical approach identified a linear combination of mRNAs for CD3ε, CD105, CD14, CD46, and 18S rRNA that distinguishes T cell–mediated rejection from antibody-mediated rejection, with a cross-validated estimate of the area under the curve of 0.81 (95% confidence interval, 0.68 to 0.93). Incorporation of these urinary cell mRNA signatures in clinical decisions may reduce the number of biopsies in patients with acute dysfunction of the kidney allograft.     

Expression of Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 in Acute Rejection of Human Renal Allografts

Background

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is expressed on various cell types and mediates homophilic cell adhesion. CEACAM1 plays an important role in cell morphogenesis and angiogenesis. Furthermore, CEACAM1 regulates adhesive activity of immune-competent cells, suggesting an additional role in inflammatory processes.

Methods

Therefore, in the present study the expression of CEACAM1 was analysed retrospectively in renal biopsies from kidney transplant recipients (stable graft [Ctr; n = 18], acute vascular rejection [AVR; n = 14], acute tubulointerstitial rejection [AIR; n = 9], and combined vascular and interstitial rejection [AVIR; n = 7]). Expression patterns of CEACAM1 were determined using immunohistochemistry and quantitative morphometry.

Results

All biopsy specimens from patients with stable grafts showed low CEACAM1 levels, suggesting a constitutive expression in renal transplants. In patients with acute rejection, CEACAM1 was markedly up-regulated. AVR revealed the highest tubular CEACAM1 levels (4.9 ± 0.5% [AVR] vs 2.2 ± 0.3% [Ctr] of tubular area; P < .05), whereas interstitial rejections showed the highest glomerular expressions (4.5 ± 0.5% [AIR] vs 0.9 ± 0.1% [Ctr] of glomerular area; P < .05).

Conclusions

An up-regulated expression of CEACAM1 in tubular and/or glomerular cells is an indicator of acute inflammatory processes in biopsy specimens from patients with acute renal allograft rejections and, therefore, might be used as a new clinical marker.     

Prediction of acute renal allograft rejection in early post-transplantation period by soluble CD30

To evaluate the feasibility of serum sCD30 for prediction of acute graft rejection, we analyzed clinical data of 231 patients, whose serum levels of sCD30 were detected by ELISA before and after transplantation. They were divided into three groups: acute rejection group (AR, n = 49), uncomplicated course group (UC, n = 171) and delayed graft function group (DGF, n = 11). Preoperative sCD30 levels of three groups were 183 +/- 74, 177 +/- 82 and 168 +/- 53 U/ml, respectively (P = 0.82). Significant decrease of sCD30 was detected in three groups on day 5 and 10 post-transplantation respectively (52 +/- 30 and 9 +/- 5 U/ml respectively, P < 0.001). Compared with Group UC and DGF, patients of Group AR had higher sCD30 values on day 5 post-transplantation (92 +/- 27 U/ml vs. 41 +/- 20 U/ml and 48 +/- 18 U/ml, P < 0.001). However, sCD30 levels on day 10 post-transplantation were virtually similar in patients of three groups (P = 0.43). Receiver operating characteristic (ROC) curve demonstrated that sCD30 level on day 5 post-transplantation could differentiate patients who subsequently suffered acute allograft rejection from others (area under ROC curve 0.95). According to ROC curve, 65 U/ml may be the optimal operational cut-off level to predict impending graft rejection (specificity 91.8%, sensitivity 87.1%). Measurement of soluble CD30 on day 5 post-transplantation might offer a noninvasive means to recognize patients at risk of impending acute graft rejection during early post-transplantation period.     

Serine proteinase inhibitor-9, an endogenous blocker of granzyme B/perforin lytic pathway,is hyperexpressed during acute rejection of renal allografts

BACKGROUND: Serine proteinase inhibitor (PI)-9 with a reactive center P1 (Glu)-P1' is a natural antagonist of granzyme B and is expressed in high levels in cytotoxic T lymphocytes (CTL). In view of the role of CTL in acute rejection, we explored the hypothesis that PI-9 would be hyperexpressed during acute rejection. Because PI-9 can protect CTL from its own fatal arsenal and potentially enhance the vitality of CTL, we examined whether PI-9 levels correlate with the severity of rejection as well as predict subsequent graft function. METHODS: We obtained 95 urine specimens from 87 renal allograft recipients. RNA was isolated from the urinary cells and mRNA encoding PI-9, granzyme B, or perforin and a constitutively expressed 18S rRNA was measured with the use of real-time quantitative polymerase chain reaction assay, and the level of expression was correlated with allograft status. RESULTS: The levels of PI-9 (P=0.001), granzyme B (P<0.0001), and perforin mRNAs (P<0.0001), but not the levels of 18S rRNA (P=0.54), were higher in the urinary cells from the 29 patients with a biopsy-confirmed acute rejection than in the 58 recipients without acute rejection. PI-9 levels were significantly higher in patients with type II or higher acute rejection changes compared with those with less than type II changes (P=0.01). Furthermore, PI-9 levels predicted subsequent graft function (r=0.43, P=0.01). CONCLUSIONS: PI-9 mRNA levels in urinary cells are diagnostic of acute rejection, predict renal allograft histology grade, and predict functional outcome following an acute rejection episode.     

CD4+CD25+调节性T细胞、Foxp3 mRNA及可溶性白细胞介素2受体检测在肾移植中的意义

目的 观察肾移植患者外周血中CD4+CD25+调节性T细胞水平及其表面特异性标志物Foxp3和可溶性白细胞介素2受体（sIL-2R）的变化，探讨其在诊断移植肾急性排斥反应中的作用和价值。 方法 选取42例维持性血液透析接受同种异体肾移植治疗的患者及30例健康体检对照者。在患者移植前、移植后1、2、4、8周或发生排斥反应时，以流式细胞仪检测外周血中CD4+CD25+调节性T细胞水平；荧光定量PCR检测Foxp3 mRNA表达；双抗体夹心酶联免疫吸附法（ELISB）检测血浆中sIL-2R水平。 结果 (1)移植后第1、2、4、8周急性排斥反应组CD4+CD25+调节性T细胞、Foxp3 mRNA水平明显低于同期未发生排斥的肾功能稳定组，而sIL-2R水平却显著高于肾功能稳定组。(2)血液透析患者外周血CD4+CD25+调节性T细胞[(9.22±3.53)%]、Foxp3 mRNA[（0.82±0.36）×10-3]及sIL-2R[（856.30±108.24） U/ml]水平与健康对照组[分别为(6.09±1.99)%、(0.50±0.28)×10-3、(247.35±11.24) U/ml]比较，差异均有统计学意义(P < 0.01)。(3)肾移植后随着肾功能的恢复，外周血CD4+CD25+调节性T细胞[(16.53±4.14)%]、Foxp3 mRNA[(4.97±1.94)×10-3]显著升高(P < 0.01)，而sIL-2R[（463.72±31.23）U/ml]水平明显降低(P < 0.01)。(4)当发生急性排斥反应时，CD4+CD25+调节性T细胞[(12.18±2.86)%]、Foxp3 mRNA[(3.15±1.22)×10-3]显著降低(P < 0.01)，而sIL-2R[(748.36±115.41) U/ml]水平明显升高(P < 0.01)，并且这些变化早于Scr的变化。(5)患者移植前后外周血CD4+CD25+调节性T细胞百分率与Foxp3 mRNA水平均呈正相关（分别为r ＝ 0.904、0.932，P < 0.01），但与sIL-2R水平无相关。 结论 外周血CD4+CD25+调节性T细胞、Foxp3 mRNA及sIL-2R水平的测定均可以作为肾移植患者移植后发生急性排斥反应的早期预测指标，并可判断预后。     

Risk Factors for Graft Loss Due to Acute Vascular Complications in Adult Renal Transplantation Using Grafts Without Vascular Anomalies

BackgroundVascular complications are the main cause of early graft loss in renal transplant (RT). A graft with multiple vessels represents the most validated risk factor. The aim of the present study was to identify potential predictive factors for acute vascular complications causing graft loss when graft vascular anomalies are excluded.MethodsThis is a retrospective case-control (1:3 ratio) study extrapolated from the RT series of the Renal Transplant Unit - Udine University Hospital, during the period 1993-2017. Grafts with multiple vessels and retransplant cases were excluded.ResultsThe overall prevalence of graft loss due to acute vascular complications was 2.6% (25/961). Seventeen complicated recipients had grafts without vascular anomalies (case group). The median time between RT and complication was 6 days (interquartile range, 4-23 days). The following types of vascular complications were recorded: 5 isolated renal artery thromboses (0.5%), 4 isolated renal vein thromboses (0.4%), 4 combined renal artery and vein thromboses (0.3%), 3 renal artery ruptures due to mycotic arteritis (0.3%), and 1 renal artery nonmycotic pseudoaneurysm (0.1%). No differences were recorded between the groups in terms of donors and grafts characteristics. Complicated recipients showed a statistically higher prevalence of thromboembolism history (P = .046) and vascular atherosclerosis (P = .048). During the postoperative course, blood stream infections (P = .02), acute rejection (P = .03), bleeding from a nonmacrovascular source (P = .04), and multiple reintervention because of nonvascular complications (P = .03) were identified as significant risk factors.ConclusionsRecipient characteristics and post-RT complications rather than donor and graft characteristics are relevant risk factors for graft loss due to acute vascular complications when graft vascular anomalies are excluded.     

Effect of histological damage on long-term kidney transplant outcome

BACKGROUND: Chronic renal allograft failure remains a major challenge to overcome. Factors such as donor quality, delayed graft function (DGF), acute rejection, and immunosuppression are known to affect long-term outcome, but their relationship to histological damage to graft outcome is unclear. METHODS: Protocol kidney biopsies (n=112) obtained at 3 months after transplantation yielded 102 with adequate tissue. Histology was scored by the Banff schema, and compared with implantation biopsies (n=91), repeat 12-month histology (n=39), decline in serum creatinine and serial isotopic glomerular filtration rate, onset of chronic allograft nephropathy (CAN), and actuarial graft survival censored for death with a functioning graft. RESULTS: At a median follow-up of 9.3 years, 20 patients had graft failure and 26 died with a functioning graft. Banff chronic nephropathy was present in 24% of 3-month biopsies, and was predicted by microvascular disease in the donor, cold ischemia, DGF, and acute vascular rejection (P<0.001). Acute glomerulitis at 3 months correlated with segmental glomerulosclerosis at 12 months, subsequent recurrent glomerulonephritis, and graft failure (P<0.01). Subclinical rejection at 3 months occurred in 29% of biopsies, correlated with prior acute rejection and HLA mismatch, and led to chronic histological damage by 12 months (r=0.25-0.67, P<0.05-0.001). Subclinical rejection, arteriolar hyalinosis, and tubulitis present at 3 months had resolved by 12 months. The 10-year survival rates for Banff chronic nephropathy were 90.4% for grade 0, 81.0% grade 1, and 57.9% for grades 2 or greater (P<0.01). Early tubulointerstitial damage at 3 months profoundly influenced graft survival beyond 10 years. CAN was predicted by kidney ischemia, 3-month chronic intimal vascular thickening, tubular injury, proteinuria, and late rejection. Chronic fibrointimal thickening of the small arteries and chronic interstitial fibrosis at 3 months independently predicted graft loss and decline in renal function (P<0.05-0.001). CONCLUSIONS: Early transplant damage occurs in the tubulointerstitial compartment from preexisting donor kidney injury and discrete events such as vascular rejection and DGF. Subsequent chronic damage and graft failure reflect accumulated previous injury and chronic interstitial fibrosis, vascular impairment, subclinical rejection, and injury from late rejection. CAN may be conceptualized as the sequelae of incremental and cumulative damage to the transplanted kidney. The duration of graft survival is dependent and predicted by the quality of the transplanted donor kidney combined with the intensity, frequency, and irreversibility of these damaging insults.     

C4d as a significant predictor for humoral rejection in renal allografts

OBJECTIVE: To determine the diagnostic and clinical significance of C4d accumulation in renal allografts followed by acute rejection. METHODS: A total of 158 graft biopsies performed from December 1997 to December 2002 were classified, according to the Banff-97 criteria, into hyperacute rejection (HAR, three cases), acute vascular rejection (AVR, 27), acute cellular rejection (ACR, 24), borderline rejection (BR, 38), acute tubular necrosis (ATN, five), stable graft function (SGF, 30) and baseline kidney (31). Immunohistochemical technique was used to determine the C4d deposition level. RESULTS: The percentages of C4d positive in HAR, AVR, ACR, BR, ATN, SGF and baseline kidney groups were 100% (3/3), 77.8% (21/27), 37.5% (9/24), 23.7% (9/38), 0% (0/5), 3.3% (1/30), 0% (0/31), respectively. In acute rejection patients, the peak serum creatinine (sCr) level in C4d(ptc)-positive group (41 cases) was 334.82 +/- 238.37 micromol/L, with that of C4d(ptc)-negative group (47 cases) being 220.20 +/- 176.94 micromol/L (p < 0.01). After treatment, the trough sCr level in C4d(ptc)-positive group and C4d(ptc)-negative group were 176.87 +/- 111.80 and 121.75 +/- 34.59 micromol/L (p < 0.01), respectively. In each AVR, ACR and BR subgroups, the peak sCr level, the trough sCr level, after 3 or 6 months of AR, the sCr level in C4d(ptc)-positive subgroup was higher than that of C4d(ptc)-negative subgroup. There were more resistance against steroid therapy [65.9% (27/41) vs. 36.2% (17/47), p = 0.005] and a higher rate of graft loss [29.3% (12/41) vs. 6.4% (3/47), p = 0.001] in C4d(ptc)-positive group than those of C4d(ptc)-negative group. In each C4d(ptc)-positive subgroup of AVR, ACR and BR the complete reversion was 57.1, 56 and 66.7%, respectively, it is almost same. CONCLUSION: The C4d deposition level is of great value in diagnosis of acute rejection caused by humoral immune components. It is a significant predictor of graft survival and will be of great help when treating acute rejection.