Differential expression of RANTES chemokine, TGF-beta, and leukocyte phenotype in acute cellular rejection and quilty B lesions.

BACKGROUND: Because of the complexity of the trabeculated endocardial surface and tangential histologic sectioning, the differentiation of acute cellular rejection (ACR) from Quilty B lesions (QB) in endomyocardial biopsies (EMBs) is problematic. We hypothesized that the phenotype chemokine RANTES (regulated upon activation, normal T cell expressed and secreted) expression of infiltrating cells and the pattern of expression of transforming growth factor-beta (TGF-beta) may distinguish ACR from QB. In previous studies, the number of RANTES-positive cells and the expression of TGF-beta correlated with the severity of rejection. METHODS: We used immunohistochemical techniques to stain sections of human EMBs with only QB (n = 14) or with only ACR (International Society for Heart and Lung Transplantation Grades 1A and 1B, n = 7; Grades 3A and 3B, n = 7) for B (CD20) and T-lymphocytes (CD3), macrophages (CD68), RANTES, and TGF-beta expression. We graded the percentage of positive cells from 0 to 4 (1 = 1% to 25%; 2 = 26% to 50%; 3 = 51% to 75%, and 4 = 76% to 100%). RESULTS: When ACR was compared with QB, we found no difference in the proportion of myocardial B cells (0.9 +/- 0.3 vs 1.1 +/- 0.3, p = 0.17); however, we found a lesser proportion of T cells (1.8 +/- 0.5 vs. 2.8 +/- 0.9, p <0.01) but more macrophages (2.9 +/- 0.5 vs. 1.1 +/- 0.6, p < 0.0001) in ACR than in QB. We also found more RANTES-positive leukocytes in ACR vs. QB (2.8 +/- 1.3 vs. 1.9 +/- 0.9, p = 0.03). In QB, many endocardial vessels stained for TGF-beta (2.9 +/- 1.6). Myocardial vessels and injured myocytes in both ACR and QB expressed TGF-beta. CONCLUSIONS: In ACR, although T-lymphocytes are numerous, more than 50% of infiltrating cells are macrophages and more than 50% express RANTES. In QB lesions, more than 50% of infiltrating cells are T-lymphocytes and less that 50% of leukocytes will express RANTES. B cells are present in both ACR and QB, but on average comprise only 25% of the cells present. Thus, a relatively simple immunohistochemical analysis of endomyocardial biopsies may be useful in distinguishing ACR from QB.     

Presence of CD163+ macrophages in DCD kidneys with high DGF reduces the risk for acute cellular rejection in 6 months after kidney transplantation

Acute cellular rejection (ACR) occurs in 10% of renal allograft recipients and is characterized by leukocyte infiltration as observed in needle biopsies. ACR onset is subject to several risk factors, including delayed graft function (DGF). As the impact of DGF on the etiology of ACR remains unclear, this study analyzed the association between presence of leukocyte subsets and ACR onset, in DCD kidney biopsies with extensive DGF following transplantation. Immunohistochemical analysis of protocol biopsies taken 10 days after kidney transplantation revealed that patients with high levels of renal CD163⁺ macrophages have a decreased risk (OR = 0.021, P = 0.008) for ACR in the first 6 months after transplantation. In pre-transplant biopsies of a comparable DCD cohort, with >80% DGF, presence of donor CD163+ macrophages showed no effect on ACR risk. Therefore, leukocyte infiltrate present during the inflammatory response at the time of DGF may contain anti-inflammatory macrophages that exert a protective effect against ACR development.     

CD20+ lymphocytes in renal allografts are associated with poor graft survival in pediatric patients

BACKGROUND: The presence of CD20+ lymphocyte renal allograft infiltrates has been associated with steroid-resistant rejection and poor graft survival. We quantified the number of CD20+ lymphocytes in renal allograft biopsies and correlated the results with graft survival. We also determined the relationships between CD20+ lymphocytes and acute cellular rejection versus antibody-mediated rejection. METHODS: We examined 45 biopsy samples from 31 pediatric patients biopsied for suspicion of rejection from November 2001 to November 2004. Immunohistochemical staining for CD20 and C4d was performed on all biopsies; CD20+ cell density per high-power field (hpf) was determined for each core. Patient graft status was followed postbiopsy and documented for graft survival or failure using the cutoff date of December 31, 2005. RESULTS: Patients with 2-10 and 11-100 CD20+ cells/hpf had worse graft survival in Kaplan-Meier analysis with a hazard ratio 4.56 (CI 1.07-19.35) two years postbiopsy compared to those with 0-1 cells/hpf (P = 0.02). The presence of CD20+ lymphocytes was significantly associated with acute cellular rejection (P = 0.0001) and not associated with antibody-mediated rejection (P = 0.16). Receiver-operating curve analysis confirmed > or =3 cells/hpf correlating with acute cellular rejection, yielding sensitivity 90% and specificity 76%. CONCLUSIONS: This study shows a significant 4.5-fold risk of graft failure at two years postbiopsy with presence of > or =2 CD20+ cells/hpf. Moreover, > or =3 CD20+ lymphocytes were highly associated with acute cellular rejection. They may be functioning as professional antigen-presenting cells in the graft. In steroid-refractory cellular rejections, therapies that target B cells may prolong graft survival.     

CD20-Positive Infiltrates in Renal Allograft Biopsies with Acute Cellular Rejection Are Not Associated with Worse Graft Survival

We examined rejection outcome and graft survival in 58 adult patients with acute cellular rejection Banff type I (ARI) or II (ARII), within 1 year after transplantation, with or without CD20-positive infiltrates. Antibody-mediated rejection was not examined. Of the 74 allograft biopsies, performed from 1999 to 2001, 40 biopsies showed ARI and 34 biopsies showed ARII; 30% of all the biopsies showed CD20-positive clusters with more than 100 cells, 9% with more than 200 cells and 5% with more than 275 cells. Patients with B cell-rich (>100 or >200/HPF CD20-positive cells) and B cell-poor biopsies (<50 CD20-positive cells/HPF) were compared. Serum creatinine and eGFR of B cell-rich (CD20 > 100/HPF) and B cell-poor were not significantly different at rejection, or at 1, 3, 6 and 12 months, and during additional 3 years follow-up after rejection, although higher creatinine at 1 year was noted in the >200/HPF group. Graft survival was also not different between B cell-rich and B cell-poor groups (p = 0.8 for >100/HPF, p = 0.9 for >200/HPF CD20-positive cells). Our data do not support association of B cell-rich infiltrates in allograft biopsies and worse outcome in acute rejection type I or II, but do not exclude the possible contribution of B cells to allograft rejection.     

Kidney Allograft Survival After Acute Rejection,the Value of Follow‐Up Biopsies

Kidney allografts are frequently lost due to alloimmunity. Still, the impact of early acute rejection (AR) on long‐term graft survival is debated. We examined this relationship focusing on graft histology post‐AR and assessing specific causes of graft loss. Included are 797 recipients without anti‐donor antibodies (DSA) at transplant who had 1 year protocol biopsies. 15.2% of recipients had AR diagnosed by protocol or clinical biopsies. Compared to no‐AR, all histologic types of AR led to abnormal histology in 1 and 2 years protocol biopsies, including more fibrosis + inflammation (6.3% vs. 21.9%), moderate/severe fibrosis (7.7% vs. 13.5%) and transplant glomerulopathy (1.4% vs. 8.3%, all p < 0.0001). AR were associated with reduced graft survival (HR = 3.07 (1.92–4.94), p < 0.0001). However, only those AR episodes followed by abnormal histology led to reduced graft survival. Early AR related to more late alloimmune‐mediated graft losses, particularly transplant glomerulopathy (31% of losses). Related to this outcome, recipients with AR were more likely to have new DSA class II 1 year posttransplant (no‐AR, 11.1%; AR, 21.2%, p = 0.039). In DSA negative recipients, early AR often leads to persistent graft inflammation and increases the risk of new DSA II production. Both of these post‐AR events are associated with increased risk of graft loss.     

Correlation between acute rejection severity and CD8-positive T cells in living related liver transplantation

The Banff schema is the most widely used standard grading system for liver allograft rejection. To investigate the relationship between the Banff rejection activity index (RAI) and the presence of lymphocyte subpopulations in allograft liver tissue, assuming these cells to probably play an important role in the mechanism of acute cellular rejection (ACR), we performed immunohistological examinations using liver tissues with various ACR severities after living related liver transplantation (LRLT). In total, 37 needle liver biopsy specimens with ACR in LRLT were examined using antibodies to CD4, CD8, and CD20. Formalin-fixed and paraffin-embedded liver tissues were used to maintain morphology. Immunohistological findings and RAI score according to the Banff schema were compared. In the results, mainly CD8-positive (CD8+), rather than CD4-positive (CD4+), cells were detected in the portal tract and were also found in bile duct epithelium and subendothelial areas of portal veins. The number of CD8+ cells increased according to ACR grade, whereas CD4+ cells tended to decrease. There were significant correlations between the presence of CD8+ cells (p = 0.0006) and CD4+ cells (p = 0.0003) and ACR severity. On the other hand, CD20-positive cells did not correlate with ACR severity (p = 0.472). The results indicate that CD8+ cells play important roles in ACR severity of LRLT, suggesting the number of CD8+ cells in liver tissue to be useful as a supplementary tool, in addition to RAI of the Banff schema, for objective evaluation of ACR severity.     

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.     

Immunophenotyping of interstitial infiltrate does not distinguish between BK virus nephropathy and acute cellular rejection

Introduction:   BK virus nephropathy (BKVN) is a significant cause of late renal allograft loss. It is characterized histologically by an interstitial nephritis that can be difficult to distinguish from acute cellular rejection (ACR). We investigated whether immunophenotyping of the infiltrate would aid this distinction.
Methods:   Ten cases of biopsy-proven BKVN, following renal transplantation, were identified from a single transplant centre. The infection was confirmed by renal biopsy and staining for SV-40 T-antigen. Biopsies from 20 consecutive patients with ACR were identified and used as controls. There was no evidence of BK infection serologically or histologically in these patients. Immunohistochemical staining with anti-CD20, perforin and granzyme B was performed on remaining tissue samples.
Results:   Clustered B cells were demonstrated in both BKVN and ACR. Hence, the CD20-stained component within the interstitial infiltrate was not useful in distinguishing these biopsies. Perforin-stained slides demonstrated fewer cytotoxic T cells in the biopsies with BK virus (average 2.4 ± 1.4 cells per 100 lymphocytes per field) compared with those samples with acute rejection (8.6 ± 5.7 cells per 100 lymphocytes, P  < 0.0001). No significant difference in granzyme B staining was detected between ACR and BKVN.
Conclusion:   Clustered B cells and granzyme B staining did not differentiate between ACR and BKVN. However, ACR cellular infiltrate was rich in perforin positive cells suggesting that perforin staining may be a useful marker to discriminate between these conditions.     

Measurement of CD4+ T‐cell function in predicting allograft rejection and recurrent hepatitis C after liver transplantation

Hashimoto K, Miller C, Hirose K, Diago T, Aucejo F, Quintini C, Eghtesad B, Corey R, Yerian L, Lopez R, Zein N, Fung J. Measurement of CD4+ T‐cell function in predicting allograft rejection and recurrent hepatitis C after liver transplantation.
Clin Transplant 2009 DOI: 10.1111/j.1399‐0012.2009.01169.x
© 2009 John Wiley & Sons A/S. Abstract: Recurrence of hepatitis C virus (HCV) can be difficult to distinguish from acute cellular rejection (ACR) following liver transplantation. The Cylex Immune Function Assay (ImmuKnow) provides objective measure of recipient’s immune function. The goal is to assess the ability of this assay to distinguish these similar conditions. A retrospective review was performed in 54 recipients with HCV. ImmuKnow assays were measured with allograft biopsies. Levels of adenosine triphosphate (ATP) release from CD4+ T cells (ng/mL) were compared with the following biopsy result classifications: 365 ± 130 with ACR (n = 11), 152 ± 100 with recurrent HCV (n = 26), 240 ± 71 with normal biopsies (n = 12), and 157 ± 130 with overlapping features of ACR and recurrent HCV (n = 5). Recipients with recurrent HCV had lower immune response than those with ACR (p < 0.0001).Using a cutoff level of 220, the sensitivity and specificity for distinguishing two conditions were 88.5% and 90.9%, respectively. When recipients with overlapping features had low immune response, three of four recipients’ subsequent biopsies showed recurrent HCV. In conclusion, the ImmuKnow assay can be a sensitive and specific additional test for distinguishing recurrent HCV from ACR and may be useful for predicting which recipients may be most vulnerable to recurrent HCV.     

Sudden, unexpected death in cardiac transplant recipients: an autopsy study.

BACKGROUND: Clinical studies indicate that sudden death (SD) is common after heart transplantation. Autopsy reports of such patients are sparse. METHODS: We performed a retrospective study of clinical and pathologic findings on all autopsied patients who underwent heart transplantation at our institution from January 1984 to July 2002. RESULTS: There were 74 patients who survived >2 months. Of these, 28 (37.8%) died suddenly. The major causes of sudden death (SD) included acute cellular rejection (ACR) (n = 11, 39.3%) and graft coronary artery disease (GCAD) (n = 11, 39.3%). In 9 patients (32.1%), there was no anatomic cause of death. These deaths, assumed to be primary arrhythmic death (PAD), occurred 5 to 36 months post-transplantation. Pre-transplant diagnosis of idiopathic dilated cardiomyopathy (IDCM) was more common in SD (13 of 28, 46.4% vs 9 of 46, 19.6%; p = 0.014). Hypertrophy was not statistically different in SD vs non-SD (79.4% vs 88.4%; p = 0.38). Coronary thrombosis was also not statistically different in sudden GCAD deaths vs non-sudden GCAD deaths (3 of 11, 27.3% vs 8 of 13, 61.5%; p = 0.09). ACR SD patients had fewer episodes of ACR in biopsies than ACR non-SD patients (93 of 190, 48.9% vs 99 of 159, 63.3%; p = 0.01). Biopsies with Quilty lesions (QL) were more frequent in patients with SD (206 of 461, 44.7% vs 243 of 710, 34.2%; p < 0.001). QL were more common in patients with GCAD (44.4%) and ACR (39.6%) than in patients who died of infection (25.7%; P < 0.001 and p < 0.01, respectively). CONCLUSIONS: SD after cardiac transplantation is common (37.8% of all deaths). ACR, in the first year, and GCAD, afterwards, are associated with SD. PAD occurred in 32.1% of SD cases, 5 to 36 months after transplantation. Pre-transplant diagnoses of IDCM and QL are more common in SD. Surprisingly, cardiac hypertrophy is not increased and coronary thrombosis is not more frequent in patients who died suddenly.     

The incidence and significance of late acute cellular rejection (>1000 days) after liver transplantation

Acute cellular rejection (ACR) after liver transplantation occurs in as much as 70% of patients within the first year. There is very little known about ACR that occurs more than 1 yr after transplant, and it is generally believed that late occurring ACR may be more resistant to medical treatment and is associated with a higher rate of chronic ductopenic rejection and graft loss. A total of 532 recipients with more than 1000 d follow-up and who did not have hepatitis C were identified. Forty-three (8.1%) had biopsy proven late ACR at a mean of 1545 +/- 441 d post-transplant. Additionally, 38 of the 43 (88.4%) patients with late ACR had earlier episodes of ACR before 1000 d post-transplant vs. only 295 of the 488 patients (60.5%) that did not have late ACR (p < 0.01). The incidence of primary sclerosing cholangitis (PSC) was 32.6% among patients with late ACR and 11.1% among patients without late ACR (p < 0.01). The overall patient survival for patients who had late ACR (n = 43) is 81.4% while for patients without late ACR (n = 488) it is 82.0% (p = ns). Patients remain at risk for ACR even after 1000 d post-transplant, particularly those with PSC.     

A Randomized,Prospective Trial of Rituximab for Acute Rejection in Pediatric Renal Transplantation

We report 1‐year outcomes of a randomized study of Rituximab versus standard‐of‐care immunosuppression (Thymoglobulin and/or pulse steroids) for treatment of biopsy confirmed, acute transplant rejection with B‐cell infiltrates, in 20 consecutive recipients (2–23 years). Graft biopsies, with Banff and CADI scores, CD20 and C4d stains, were performed at rejection and 1 and 6 months later. Peripheral blood CMV, EBV and BK viral loads, graft function, DSA, immunoglobulins, serum humanized antichimeric antibody (HACA) and Rituximab, and lymphocyte counts were monitored until 1 year posttreatment. Rituximab infusions were given with a high index of safety without HACA development and increased infections complications. Rituximab therapy resulted in complete tissue B‐cell depletion and rapid peripheral B‐cell depletion. Peripheral CD19 cells recovered at a mean time of ～12 months. There were some benefits for the recovery of graft function (p = 0.026) and improvement of biopsy rejection scores at both the 1‐ (p = 0.0003) and 6‐month (p < 0.0001) follow‐up biopsies. Reappearance of C4d deposition was not seen on follow‐up biopsies after Rituximab therapy, but was seen in 30% of control patients. There was no change in DSA in either group, independent of rejection resolution. This study reports safety and suggests further investigation of Rituximab as an adjunctive treatment for B‐cell‐mediated graft rejection.     

CD19+CD24hiCD38hi B细胞比例预测肝移植术后急性细胞性排斥反应发生的临床研究

目的分析肝移植术后受者外周血CD19⁺CD24^hiCD38^hi B细胞占单个核细胞比例变化情况及其与急性细胞性排斥反应(ACR)之间的关系。 方法回顾性分析2013年12月至2015年12月在浙江大学医学院附属第一医院接受心脏死亡器官捐献肝移植的80例成人受者临床资料，根据术后是否发生ACR，将受者分为ACR组(25例)和非ACR组(55例)。术前、术后各个时间点抽取参加研究者静脉血并分离外周血单个核细胞，加入异硫氰酸荧光素-单克隆鼠抗人CD19抗体、藻红蛋白-单克隆鼠抗人CD24抗体和别藻蓝蛋白-单克隆鼠抗人CD38抗体，流式细胞仪检测各组CD19⁺CD24^hiCD38^hi B细胞百分比。采用t检验和单因素方差分析比较正态分布计量资料，采用χ²检验比较计数资料，采用Kaplan-Meier法绘制受试者工作特征曲线(ROC曲线)。P<0.05为差异有统计学意义。 结果ACR组、非ACR组受者术前外周血平均CD19⁺CD24^hiCD38^hi B细胞比例分别为(3.13±0.91)%、(3.49±0.83)%，差异无统计学意义(t＝1.636，P>0.05)。ACR组术后发生ACR前外周血平均CD19⁺CD24^hiCD38^hi B细胞比例为(1.87±0.70)%。非ACR组受者术后3个月、6个月和1年外周血平均CD19⁺CD24^hiCD38^hi B细胞比例分别为(1.64±0.52)%、(1.63±0.56)%和(2.04±1.24)%，术后3、6个月平均值均低于术前和术后1年，差异均有统计学意义(P均<0.05)。ACR组受者发生ACR时外周血平均CD19⁺CD24^hiCD38^hi B细胞比例为(0.8±0.5)%，低于发生ACR前的平均水平(t＝5.752，P<0.05)，且低于非ACR组术后3个月、6个月和1年的平均水平(P<0.05)。ACR组受者接受抗排斥反应治疗后，CD19⁺CD24^hiCD38^hi B细胞比例也逐渐增加，ACR发生后7 d为(0.84±0.08)%，与ACR发生时相比差异无统计学意义(P>0.05)；而发生30 d后达(1.65±0.18)%，与ACR发生时相比差异有统计学意义(P<0.05)。当截断值为1.015%时，CD19⁺CD24^hiCD38^hi B细胞比例预测ACR发生的敏感度和特异度分别为0.786和0.702，ROC曲线下面积为0.775(95%CI: 0.671~0.879，P<0.05)。 结论CD19⁺CD24^hiCD38^hi B细胞比例下降与肝移植术后ACR反应发生有关，并可作为预测ACR发生的细胞标志物。     

Immunephenotype of Glomerular and Interstitial Infiltrating Cells in Protocol Renal Allograft Biopsies and Histological Diagnosis

Patients with a protocol renal allograft biopsy simultaneously displaying interstitial fibrosis/tubular atrophy (IF/TA) and subclinical rejection (SCR) have a shortened graft survival than patients with a normal biopsy, or with a biopsy only displaying IF/TA or SCR. The poor outcome of these patients could be related with a more severe inflammation. We evaluate the immunophenotype of infiltrating cells in these diagnostic categories. Nonexhausted paraffin blocks from protocol biopsies done during the first year were stained with anti-CD45, CD3, CD20, CD68 and CD15 monoclonal antibodies. Glomerular and interstitial positive cells were counted. C4d deposition in peritubular capillaries was evaluated. Histological diagnoses were: normal (n = 80), SCR (n = 17), IF/TA (n = 42) and IF/TA + SCR (n = 17). Only interstitial CD20 positive cells were significantly increased in patients displaying IF/TA + SCR; normal (137 +/- 117), SCR (202 +/- 145), IF/TA (208 +/- 151) and IF/TA + SCR (307 +/- 180 cells/mm(2)), p < 0.01. The proportion of biopsies displaying C4d deposition was not different among groups. The upper tertile of CD20 positive interstitial cells was associated with a decreased death-censored graft survival (relative risk: 3.01, 95% confidence interval: 1.23-7.35; p = 0.015). These data suggest that B-cell interstitial infiltrates are associated with histological damage and outcome, but do not distinguish whether these infiltrates were the cause or the consequence of chronic tubulo-interstitial damage.     

The terminal ileum is affected in patients with lymphocytic or collagenous colitis

Lymphocytic colitis (LC) and collagenous colitis (CC) are diseases characterized by the presence of marked intraepithelial lymphocytosis. Both of these disorders affect primarily the colon. However, involvement of the distal small intestine has not been systematically studied. The purpose of this study was to evaluate the type and degree of intraepithelial lymphocytosis in the terminal ileum of patients with LC or CC. Terminal ileal mucosal biopsies from 22 patients with LC (male/female ratio 0.22, mean age 47 years) and 23 with CC (male/female ratio 0.43, mean age 54 years) were evaluated for the number of intraepithelial lymphocytes (IEL) per 100 epithelial cells (EC) both in the villi and crypts. The results were compared with 30 patients with inflammatory bowel disease (16 with Crohn's disease [CD], 14 with ulcerative colitis [UC]) and 24 patients (male/female ratio 0.33, mean age 44 years) without colonic pathology as normal controls. None of the patients had celiac sprue. Paired terminal ileum and colonic mucosal biopsies from 6 patients with LC, 4 with CC, 5 with CD, 5 with UC, and 10 normal controls were also immunohistochemically stained with monoclonal antibodies to CD3, CD8, CD20, and a class II MHC antigen (LN3-HLA-DR). In the villi the IEL count/100 EC was 11.8 +/- 1.8 in LC and 10.3 +/- 1.9 in CC (p = 0.3). These values were both significantly higher than in CD (2.8 +/- 0.4, p <0.001), UC (3.1 +/- 0.4, p <0.001), or normal controls (2.2 +/- 0.2, p <0.001). In the crypts the IEL count was 3.8 +/- 0.5 in LC and 3.2 +/- 0.5 in CC (p = 0.3). These values were also significantly higher than in CD (2.3 +/- 0.4, p = 0.02), UC (2.1 +/- 0.3, p = 0.02), or normal controls (1.5 +/- 0.2, p <0.001). The presence of >5 IELs/100 EC in terminal ileum biopsies was highly specific for LC and CC (specificity 98%, sensitivity 73% and 56% for LC and CC, respectively). The IEL phenotype was similar in all groups of patients and in the ileum and colon of individual patients. Intraepithelial lymphocytes were CD3+, CD8+, CD20-, and LN3-HLA-DR-, indicative of a suppressor T-cell phenotype. Intraepithelial lymphocytosis occurs in the terminal ileum in patients with LC or CC and may be helpful in diagnosing these conditions and distinguishing LC or CC from CD or UC in diagnostically difficult cases. The results suggest that the terminal ileum may be involved by a similar pathogenic process as the colon in LC and CC.     

Renal allograft biopsies in the era of C4d staining: the need for change in the Banff classification system.

C4d immunostaining in the peritubular capillaries (PTC) is a marker of antibody-mediated rejection (AMR). We evaluated the histopathologic diagnoses of 388 renal transplant biopsies since the implementation of routine C4d immunostaining at our center. Of these, 155 (40%) biopsies had evidence of acute cellular rejection (ACR), out of which 119 (77%) had pure ACR, 31 (20%) had ACR with concomitant features of AMR, and five (3%) had ACR with focal C4d staining. Sixty-four (16%) biopsies exhibited features of AMR [33 (52%) pure AMR, and 31(48%) concomitant AMR and ACR]. One hundred and fifty-five (40%) biopsies had features of interstitial fibrosis and tubular atrophy (IFTA). Of these, 20 (13%) had concomitant AMR [13 (8.5%) had pure AMR and seven (4.5%) had concomitant ACR and AMR]. Creatinine at the time of biopsy was higher in patients with mixed ACR and AMR and the clinical behavior of mixed lesions is more aggressive over time. Despite having a lower serum creatinine at the time of biopsy, patients with IFTA experienced gradual decline in graft function over time. The pathologic findings in renal allograft biopsies are often mixed and mixed lesions appear to have more aggressive clinical behavior. These findings suggest the need for change in the Banff classification system to better capture the complexity of renal allograft pathologies.     

The presence of B-cell nodules does not necessarily portend a less favorable outcome to therapy in patients with acute cellular rejection of a renal allograft

The presence of B-cell nodules in kidney biopsies of patients undergoing acute renal allograft rejection has been reported to be associated with glucocorticoid resistance and a high risk of graft failure. In an attempt to corroborate this observation, biopsies of renal transplants that evidenced Banff grade I A acute rejection were examined for the presence of B- or T-cell nodules, the detection of which was correlated with the therapeutic response. Biopsies from 14 consecutive renal transplant recipients with a diagnosis of acute cellular rejection were examined for the presence of T (CD3-positive) or B (CD20-positive) cells by immunohistochemistry. All patients were biopsied because of a rise in serum creatinine. No biopsy showed evidence of acute humoral rejection. Immunofluorescence microscopy was negative for C4d deposition in peritubular capillaries. There were no neutrophils in the peritubular or glomerular capillaries. Five patients had T-cell nodules; four had B-cell nodules; three had both T- and B-cell nodules; two had no nodules. All biopsies contained CD3-positive cells in the tubules and in the interstitium. In all but one of the patients, episodes of acute rejection were treated with steroids (one received thymoglobulin). Furthermore two patients received mycophenolate mofetil and one, sirolimus. There were no significant differences among the groups in either the initial creatinine or the creatinine after therapy. The presence of B-cell nodules in renal allograft biopsies of patients experiencing acute cellular rejection did not portend a less favorable outcome.     

小肠移植术后内镜引导下移植肠黏膜活检的时机及诊断价值

目的 总结小肠移植术后内镜引导下移植肠黏膜活检的时机及该技术对急性排斥反应和感染的诊断价值.方法 根据免疫抑制方案的不同,将15例小肠移植受者分为3个阶段.1994-1995年为第1阶段(3例),2003-2006年为第2阶段(7例),2007年以后为第3阶段(5例).第3阶段进行计划性内镜引导下移植肠黏膜活检的监测,既术后第3天进行首次内镜引导下移植肠黏膜活检,此后活检的频次在术后第1个月为2次/周,术后第2～3个月为1次/周,术后第4～6个月为1次/2周,术后7个月以后为1次/月,在受者出现排斥反应的临床症状和抗排斥反应治疗期间,也进行内镜引导下移植肠黏膜活检.结果 15例共进行内镜引导下移植肠黏膜活检255次,移植肠腹壁造口肉眼直视下取材活检21次.以上276份样本中,诊断排斥反应共51份(18.5%),其中诊断不确定急性排斥反应至轻度排斥反应32份(11.6%)、中度排斥反应9份(3.3%)、重度排斥反应10份(3.6%),巨细胞病毒(CMV)感染2份(0.7%),细菌感染2份(0.7%).15例共发生病理证实并需l临床治疗的排斥反应20次,其中不确定急性排斥反应至轻度排斥反应11次、中度5次、重度4次,发生细菌性和CMV肠炎各1次.结论 内镜引导下移植肠黏膜活检及其病理学检查是小肠移植术后诊断排斥反应和感染的重要手段,有计划的进行该检查对排斥反应有术后监测、早期诊断、鉴别诊断和指导治疗的价值.     

Pancreas Transplantation With Enteroanastomosis to Native Duodenum Poses Technical Challenges—But Offers Improved Endoscopic Access for Scheduled Biopsies and Therapeutic Interventions

To facilitate endoscopic access for rejection surveillance and stenting of the pancreas, we have abandoned the duodenojejunostomy (DJ) in favor of duodenoduodenostomy (DD) in pancreas transplantation (PTx). From September 2012 to September 2013 we performed 40 PTx with DD; 20 solitary‐PTx (S‐PTx) and 20 simultaneous pancreas and kidney transplantation (SPK). We compared the outcomes with results from 40 PTx‐DJ (10 S‐PTx and 30 SPK) from the preceding era. The DD‐enteroanastomoses were performed successfully. Endoscopic pancreas biopsies (endoscopic ultrasound examination [EUS]) yielded representative material in half of the cases. One exocrine fistula was treated by endoscopic stenting. PTxs‐DD were associated with a higher rate of thrombosis compared to PTx‐DJ (23% vs. 5%) and reoperations (48% vs. 30%), as well as inferior graft survival (80% vs. 88%). Time on waiting list, HLA A + B mismatches and reoperations were associated with graft loss. Only recipient age remained an independent predictor of patient death in multivariate analysis. PTx‐DD showed a higher rate of thrombosis and inferior results, but facilitated a protocol biopsy program by EUS that was feasible and safe. Given that technical difficulties can be solved, the improved endoscopic access might confer long‐term benefits, yet this remains to be proven.