IL-10 Signaling in the Tumor Microenvironment of Ovarian Cancer

Unlike other malignancies, ovarian cancer (OC) creates a complex tumor microenvironment with distinctive peritoneal ascites consisting of a mixture of several immunosuppressive cells which impair the ability of the patient's immune system to fight the disease. The poor survival rates observed in advanced stage OC patients and the lack of effective conventional therapeutic options have been attributed in large part to the immature dendritic cells (DCs), IL-10 secreting regulatory T cells, tumor-associated macrophages, myeloid-derived suppressor cells, and cancer stem cells that secrete inhibitory cytokines. This review highlights the critical role played by the intraperitoneal presence of IL-10 in the generation of an immunosuppressive tumor microenvironment. Further, the effect of antibody neutralization of IL-10 on the efficacy of DC and chimeric antigen receptor T-cell vaccines will be discussed. Moreover, we will review the influence of IL-10 in the promotion of cancer stemness in concert with the NF-κB signaling pathway with regard to OC progression. Finally, understanding the role of IL-10 and its crosstalk with various cells in the ascitic fluid may contribute to the development of novel immunotherapeutic approaches with the potential to kill drug-resistant OC cells while minimizing toxic side effects.

Outcomes of cholecystectomy in US veterans with cirrhosis: Predicting outcomes using nomogram

BACKGROUND

This study examines the outcomes of open and laparoscopic cholecystectomy (OC/LC) in veterans with cirrhosis and develops a nomogram to predict outcomes.

METHODS

We analyzed the Veterans Affairs Surgical Quality Improvement Program to identify all patients with cirrhosis and ascites who underwent cholecystectomy from 2008 to 2015. Univariate and multivariate regression were used to identify predictors of morbidity and mortality. A predictive nomogram was constructed and internally validated.

RESULTS

A total of 349 patients were identified. Overall, complications occurred in 18.7% of patients, and mortality was 3.8%. LC was performed in 58.9%, and 19.2% were preformed emergently. Overall, Model for End-Stage Liver Disease score was an independent factor of morbidity and mortality, while laparoscopic approach had a protective effect on morbidity.

CONCLUSIONS

Although cholecystectomy is a high-risk operation in cirrhotic veterans, LC may have favorable outcomes than OC in selected patients. An easy-to-use nomogram to predict morbidity and mortality for cirrhotic patients undergoing cholecystectomy is proposed.

Postoperative outcomes of ventral hernia repair in veterans

BACKGROUND

Ventral hernia repair is a common procedure with reported 15% to 37% morbidity and 0.3% to 1.4% mortality rates. This study examines the 30-day morbidity and mortality of open and laparoscopic ventral hernia repair in veterans, along with the impact of body mass index on these outcomes.

METHODS

The Veterans Affairs Surgical Quality Improvement Program was queried for all ventral hernia repairs during the period 2008 to 2015. In this retrospective analysis, we compared outcomes of open ventral hernia repair versus laparoscopic ventral hernia repair and among different body mass index classes.

RESULTS

A total of 19,883 patients were identified (92.6% male, mean age 59.7, 53.1% obese, and 71.6% with American Society of Anesthesiologists class ≥III). There were 95 (0.5%) mortalities, and complications occurred in 1,289 (6.5%) patients. Open ventral hernia repair was performed in 60.2%; 14.5% were recurrent, and 3.3% were performed as an emergency operation. When compared with open ventral hernia repair, the laparoscopic ventral hernia repair group had higher mean body mass index, less patients with American Society of Anesthesiologists class ≥III, fewer emergency operations, longer operative time, less complications, decreased mortality, and shorter duration of stay. Body mass index 35.00 to 49.99 was predictive of overall complications in the open ventral hernia repair group.

CONCLUSION

Ventral hernia repair can be performed in the veteran population with outcomes comparable to those in the private sector. Morbid obesity has a negative impact on ventral hernia repair outcomes that is most prominent following open surgery. Laparoscopic ventral hernia repair may offer superior outcomes when compared to open ventral hernia repair and may be considered.

Recent trends in cholecystectomy in US veterans

INTRODUCTION

We hypothesize that the recent trend in performing cholecystectomy in US Veterans shows wide adoption of the laparoscopic technique and improvement in the outcome following both laparoscopic (LC) and open cholecystectomy (OC). This study utilizes the Veterans Affairs Surgical Quality Improvement Program database to examine the status and outcome of cholecystectomy.

METHODS

A retrospective review of veterans who underwent cholecystectomy between 2008 and 2015 was performed. Data analysis included patient demographics, operations, and postoperative outcomes. Cochran-Armitage trend analysis was used to assess significant changes in outcome over the study period. p ≤ 0.05 was considered significant.

RESULTS

A total of 40,722 patients (average age of 61 years) were included in the study (males 85.6%). LC was performed in the majority of patients (86.4%). Patients in the OC group (13.6%) were more likely to have advanced age (≥ 65 years) (47.6% vs 32.0%, p < 0.001) and higher ASA class (III-V) (81.9% vs 65.4%, p < 0.001) than those in the LC group. Compared with LC, OC had higher mortality rates at 30 days (1.3% vs 0.3%; OR = 1.6, p = 0.03), 3 months (2.6% vs 0.7%; OR = 1.7, p < 0.001), 6 months (3.9% vs 1.1%; OR = 1.5, p < 0.001) and 1 year (5.7% vs 2.0%; OR = 1.5, p < 0.001); higher rates of morbidity, including pneumonia (OR = 1.9, p < 0.001), deep venous thrombosis (OR = 2.4, p = 0.02), reoperation (OR = 1.8, p < 0.001), and superficial (OR = 4.9, p < 0.001) and deep (OR = 1.5, p = 0.01) surgical site infections; and a longer length of stay (6.5 days vs 2.6 days, p < 0.001). Trend analysis showed a significant decrease in both mortality (p = 0.02) and morbidity (p < 0.001) for LC over the study period, but no improvement in mortality (p = 0.35) and a only a minimal improvement in morbidity (p = 0.04) for OC.

CONCLUSION

In the recent era, LC has been widely performed in the VA with significant improvement in outcome. Efforts are needed to adopt alternative approaches to planned OC and to improve postoperative outcomes.

Engraftment of mesothelin chimeric antigen receptor using a hybrid Sleeping Beauty/minicircle vector into NK-92MI cells for treatment of pancreatic cancer

BACKGROUND

We have previously demonstrated in vitro cytotoxicity of mesothelin-chimeric antigen receptor autologous T cells against pancreatic cancer cells using lentiviral vectors, but these vectors pose safety concerns. Here, we incorporated Sleeping Beauty and minicircle design enhancements into interleukin-2-secreting natural NK-92MI cells to eliminate both bacterial and viral components and address inhibition by the tumor microenvironment.

METHODS

Parental (conventional deoxyribonucleic acid)-mesothelin-chimeric antigen receptor and minicircle-mesothelin-chimeric antigen receptor vectors were electroporated into NK-92MI cells and engraftment was visualized by immunofluorescence analysis with protein-L staining. Interferon-γ and granzyme B secretion were measured by enzyme-linked immunosorbent assay from cocultures of parental-mesothelin-chimeric antigen receptors and minicircle-mesothelin-chimeric antigen receptors with human pancreatic cancer cells, and cytotoxicity of chimeric antigen receptor NK-92MI cells was tested against three pancreatic cancer cell lines.

RESULTS

Cloning of mesothelin-chimeric antigen receptor Sleeping Beauty into a minicircle vector removed its bacterial backbone and reduced its size with improved electroporation efficiency. Chimeric antigen receptor engraftment, Interferon-γ and granzyme B secretion, and specific lysis against all three pancreatic cancer lines were significantly increased with minicircle-mesothelin-chimeric antigen receptor versus parental-mesothelin-chimeric antigen receptor NK-92MI cells.

CONCLUSION

We provide proof of concept that allogeneic mesothelin-chimeric antigen receptor NK-92MI cells with hybrid Sleeping Beauty and minicircle technologies provide increased engraftment and cytotoxicity in vitro with potential safety benefits when translated to the clinical arena.

Inhibition of Interleukin-10 in the tumor microenvironment can restore mesothelin chimeric antigen receptor T cell activity in pancreatic cancer in vitro

BACKGROUND

Pancreatic cancer cells are known to shield themselves from immunosurveillance by secreting immune inhibitory cytokines such as Interleukin-10. Using mesothelin, a differentiating antigen that is overexpressed in pancreatic cancer, we assessed the negative effect of the tumor microenvironment on chimeric antigen receptor T cell-based immunotherapy and its reversal via depletion of Interleukin-10.

METHODS

T cells cultured in pancreatic cancer-cell-conditioned medium were transduced with lentiviruses encoding mesothelin-chimeric antigen receptor in the presence or absence of anti-Interleukin-10-blocking antibody.

RESULTS

Coculture supernatants of conditioned medium displayed significant inhibition of interferon γ and granzyme B secretion, both of which are crucial for induction of target cell cytotoxicity. In contrast, this inhibition was restored toward baseline when conditioned medium was Interleukin-10- depleted (p < .05 for both interferon γ and granzyme B). In addition, we observed a significant decrease in mesothelin-chimeric antigen receptor T cell-induced cytotoxicity of BxPC-3 target cells in the presence of conditioned medium. Furthermore, we observed a partial blunting of this inhibition when Interleukin-10 was depleted from the conditioned medium.

CONCLUSION

Substantial reversal of tumor-derived immunosuppression may be achieved by blocking Interleukin-10 in the local microenvironment, allowing for more effective cytotoxicity of mesothelin-engrafted chimeric antigen receptor T cells and enhancing the potential for clinical application.

The impact of initiation: Early onset marijuana smokers demonstrate altered Stroop performance and brain activation

Marijuana (MJ) use is on the rise, particularly among teens and emerging adults. This poses serious public health concern, given the potential deleterious effects of MJ on the developing brain. We examined 50 chronic MJ smokers divided into early onset (regular MJ use prior to age 16; n=24) and late onset (age 16 or later; n=26), and 34 healthy control participants (HCs). All completed a modified Stroop Color Word Test during fMRI. Results demonstrated that MJ smokers exhibited significantly poorer performance on the Interference subtest of the Stroop, as well as altered patterns of activation in the cingulate cortex relative to HCs. Further, early onset MJ smokers exhibited significantly poorer performance relative to both HCs and late onset smokers. Additionally, earlier age of MJ onset as well as increased frequency and magnitude (grams/week) of MJ use were predictive of poorer Stroop performance. fMRI results revealed that while late onset smokers demonstrated a more similar pattern of activation to the control group, a different pattern was evident in the early onset group. These findings underscore the importance of assessing age of onset and patterns of MJ use and support the need for widespread education and intervention efforts among youth.

Enhanced phosphorylation of p53 by microRNA-26a leading to growth inhibition of pancreatic cancer

PURPOSE

MicroRNA (miR)-26a has been identified as a tumor suppressor in pancreatic cancer cells. Although wild-type p53 controls cell-cycle progression, its mutant form normally present in pancreatic cancer loses this capability. Phosphorylation is known to restore wild-type activity to mutant p53. We, therefore, examined whether miR-26a treatment can restore wild-type functions of mutant p53 via phosphorylation, resulting in inhibition of cell growth.

METHODS

The human pancreatic cancer cell line BxPc-3 harboring mutant p53 was used for colony formation, cell-cycle, and Western blotting assays. Gene profile analysis was conducted after transfection with pre-miR-26a.

RESULTS

miR-26a expression significantly decreased cell proliferation by 80% along with marked inhibition of colony formation and cell migration. Cell-cycle inhibition at the G0/G1 interface was observed along with enhanced drug retention and increased chemosensitivity to gemcitabine. Mutant p53 was phosphorylated rapidly at its Ser9 and Ser392 residues, but not at Ser15 or Ser20. Gene profile analysis of pre-miR-26a-transfected cells showed a significant increase in gene transcripts promoting apoptosis and p53 activation, with decreased levels of genes involved in cell-cycle progression.

CONCLUSION

Delivery of miR-26a may represent a novel strategy for inhibiting pancreatic cancer growth, at least in part by enhancing phosphorylation of mutant p53 to restore its wild-type functions.

MAGE-A3 with cell-penetrating domain as an efficient therapeutic cancer vaccine

IMPORTANCE

In conjunction with chemotherapy, immunotherapy with dendritic cells (DCs) may eliminate minimal disease burden by generating cytotoxic T lymphocytes. Enhanced cytosolic bioavailability of tumor-specific antigens improves access to human leukocyte antigen (HLA) class I molecules for more efficient cytotoxic T lymphocyte generation. Various cell-penetrating domains (CPDs) are known to ferry covalently linked heterologous antigens to the intracellular compartment by traversing the plasma membrane.

OBJECTIVE

To determine whether generating melanoma antigen family A, 3 (MAGE-A3), a tumor-specific cancer-testis antigen, as a fusion protein with CPD will enhance the cytosolic bioavailability of MAGE-A3.

DESIGN

MAGE-A3 was amplified by polymerase chain reaction using complementary DNA from renal tissue and cloned in frame with a CPD (YARKARRQARR) at the amino-terminal end and hexahistidine at the carboxy-terminal end to generate CPD-MAGE-A3 in a pQE-70 expression vector. Cultures were grown in Escherichia coli BL21 Star (DE3-pLysS) cells followed by nickel-nitrilotriacetic acid affinity purification of recombinant proteins.

MAIN OUTCOMES AND MEASURES

Measurement of DC membrane penetration of CPD-MAGE-A3 vs MAGE-A3 and determination of the effect of CPD-MAGE-A3 pulsing on DC phenotypic expression of cell-surface antigens.

RESULTS

Media composition and isopropyl-d-thiogalactosidase induction were optimized to achieve high levels of protein expression followed by purification. Western blot analysis with MAGE-A3 antibodies recognized both MAGE-A3 and CPD-MAGE-A3 proteins, while CPD antibodies recognized only CPD-MAGE-A3. Purified CPD-MAGE-A3 exhibited more efficient DC membrane penetration than did MAGE-A3 alone as confirmed by immunofluorescence analysis. High-level expression of several unique DC markers (CD80, CD83, CD86, and HLA-DR) by flow cytometry was consistent with a mature DC phenotype, indicating that pulsing with CPD-MAGE-A3 did not alter specific cell-surface antigens required for T-cell activation.

CONCLUSIONS AND RELEVANCE

We have demonstrated for the first time, to our knowledge, that cloning and purification of MAGE-A3 with CPD enhances its cytosolic bioavailability in DCs without altering cell-surface antigens, potentially making it a more potent therapeutic cancer vaccine compared with existing MAGE-A3 protein and peptide vaccines.

EZH2-shRNA-mediated upregulation of p21waf1/cip1 and its transcriptional enhancers with concomitant downmodulation of mutant p53 in pancreatic ductal adenocarcinoma

PURPOSE

Enhancer of zeste homologue 2 (EZH2), a component of the chromatin modification protein complex, is upregulated in pancreatic ductal adenocarcinoma (PDAC), whereas loss of p53 and its downstream target, p21(waf1/cip1), is also observed frequently. We sought to investigate the role of the p53-p21(waf1/cip1) pathway in relation to EZH2-mediated inhibition of PDAC.

METHODS

The PANC-1 cell line was utilized in chromatin immunoprecipitation, gene profiling, Western blot, cell invasion, cell proliferation, and tumor xenograft assays.

RESULTS

Western blot analysis with antibodies that recognize both wild-type and mutant p53 did not show any alterations in band intensity; however, antibody that detects only mutant p53 showed a band of significantly lesser intensity with EZH2 knockdown. Western blot analysis further revealed a significant upregulation of p21(waf1/cip1). Gene expression profile analysis indicated significantly enhanced transcripts of transcriptional inducers of p21(waf1/cip1), with downregulation of mutant p53 transcript, corroborating the Western blot analysis. PANC-1 cells expressing EZH2-short hairpin RNA displayed markedly attenuated growth in SCID mice.

CONCLUSION

Downregulation of mutant p53 with concomitant enhanced expression of p21(waf1/cip1) and its transcriptional trans-activators may contribute toward EZH2-mediated suppression of PDAC.

EZH2 blockade by RNA interference inhibits growth of ovarian cancer by facilitating re-expression of p21(waf1/cip1) and by inhibiting mutant p53

The enhancer of zeste homolog 2 (EZH2) methyltransferase is a transcriptional repressor. EZH2 is abnormally elevated in epithelial ovarian cancer (EOC). We demonstrated that EZH2 knockdown inhibited cell growth, activated apoptosis, and enhanced chemosensitivity. Further, silencing of EZH2 resulted in re-expression of p21(waf1/cip1) and down-regulation of mutant p53. Finally, EZH2 knockdown contributed to attenuated EOC growth in SCID mice.

Restoration of E-cadherin expression in pancreatic ductal adenocarcinoma treated with microRNA-101

PURPOSE

To investigate the possibility of inhibiting the progression of pancreatic ductal adenocarcinoma (PDAC) by facilitating the expression of E-cadherin through the enforced expression of microRNA-101 (miR-101).

METHODS

In situ hybridization was conducted with archival tissue using a double digoxigenin-labeled probe. Chromatin immunoprecipitation (ChIP) assay was conducted with EZ-Magna ChIPTM A. Gene profile analysis, Western blot, and immunoprecipitation assays were performed using standard protocols.

RESULTS

We found that decreased miR-101 expression observed in archival patient tissues was significantly associated with poor prognosis indicated by low-intensity staining in high-grade tumors. ChIP assays using anti-enhancer of zeste homolog 2 (EZH2) antibodies indicated not only the interaction of EZH2 to the CDH1 (E-cadherin) promoter, but also that this interaction was significantly diminished in cells transfected with pre-miR-101. We observed a global downregulation of trimethylated lysine 27 of H3 histone (H3K27me3) along with upregulation of the enzymes histone deacetylase -1 and -2 with the re-expression of miR-101. Further, we observed lesser levels of transcriptional factors that inhibit the CDH1 promoter with pre-miR-101 treatment. Western blot analysis confirmed the enhanced E-cadherin expression. PANC-1 cells transduced with pre-miR-101 displayed markedly attenuated growth in SCID mice.

CONCLUSION

These results suggest the potential therapeutic use of miR-101-enforced expression for inhibition of PDAC.

MicroRNA-101 inhibits growth of epithelial ovarian cancer by relieving chromatin-mediated transcriptional repression of p21(waf¹/cip¹)

PURPOSE

MicroRNA-101 (miR-101) expression is negatively associated with tumor growth and proliferation in several solid epithelial cancers. Enhancer of zeste homolog 2 (EzH2) appears to be a functional target of miR-101. We explore the role of miR-101 and its interaction with EzH2 in epithelial ovarian carcinoma (EOC).

METHODS

In situ hybridization (ISH) for miR-101 was performed on EOC patient tissues and normal controls. EOC cell lines were transfected with miR-101 and subjected to growth analysis and clonogenic assays. Cell motility was assessed by Boyden chamber and wound-healing assays. P21(waf1/cip1) and EzH2 interaction was assessed by Chromatin Immunoprecipitation (ChIP) assay in MDAH-2774 cells. SCID mice were assessed for tumor burden after injection with miR-101 or control vector-treated MDAH-2774 cells.

RESULTS

ISH analysis revealed a decrease in miR-101 expression in EOC compared with normal tissue. MiR-101 re-expression in EOC cell lines resulted in increased apoptosis, decreased cellular proliferation, invasiveness, and reduced growth of tumor xenografts. CHIP assays revealed that re-expression of miR-101 inhibited the interaction of EzH2 with p21(waf1/cip1) promoter.

CONCLUSIONS

MiR-101 re-expression appears to have antitumor effects, providing a better understanding of the role of miR-101 in EOC.

Different patterns of cancer incidence among African American and Caucasian renal allograft recipients

BACKGROUND

Little data are available regarding cancer incidence in separately analyzed African American renal allograft recipients, with no study examining in detail the incidence and relative distribution of individual post-transplant malignancies versus those occurring in Caucasians.

METHODS

We compared the incidence of nonskin cancer occurring in 495 African Americans transplanted at our center from 1984 to 2007 and followed through June 2009 with that occurring in 11,155 patients in the Canadian Organ Replacement Registry transplanted from 1981 to 1998 and followed through December 1999, of which 97% were Caucasian.

RESULTS

Despite a shorter follow-up, the overall incidence of nonskin cancer, as well as that of prostate, renal cell, pancreatic, and esophageal cancer, was significantly higher in the African American group. Cancers of the prostate and pancreas comprised a significantly higher fraction of neoplasms occurring in the African American group, whereas lip cancer did so in the Canadian Organ Replacement Registry group.

CONCLUSION

In our pilot study, the overall incidence of nonskin cancers was higher in African American versus Caucasian renal allograft recipients, reflecting a significantly different relative distribution of cancer types that follows cancer incidence trends by race in the general population in several but not all cases. If verified in subsequent studies, these findings have important implications with regard to the need for transplant programs to tailor cancer education and pretransplant and post-transplant surveillance appropriately to the African American patient.

Does donor race still make a difference in deceased-donor African-American renal allograft recipients?

BACKGROUND

Prior studies have demonstrated that African-American (AA) donor kidneys are independently associated with an increased risk for graft loss.

METHODS

We examined outcomes in comparable groups of AA deceased-donor (DD) kidney transplant patients receiving an AA donor (n=35) versus a Caucasian donor (C group; n=150) organ.

RESULTS

There were no differences between AA and C groups in patient survival, new-onset diabetes, or BK nephropathy. The AA group demonstrated a significantly higher 6-month and overall incidence of acute rejection (AR), increased cytomegalovirus (CMV) infection, and decreased graft survival. Recurrent or de novo focal segmental glomerulosclerosis (FSGS) accounted for a significantly higher fraction of graft losses in the AA versus C group.

CONCLUSIONS

AA DD renal allograft recipients have equivalent patient but decreased graft survival when transplanted with an AA versus C kidney using current immunosuppression. This may be the result of increased AR, CMV infection, and recurrence/development of FSGS.

Differentiation of alloreactive versus CD3/CD28 stimulated T-lymphocytes using Raman spectroscopy: a greater specificity for noninvasive acute renal allograft rejection detection

Acute rejection (AR) remains problematic in renal transplantation. As a marker, serum creatinine is limited, warranting a more effective screening tool. Raman spectroscopy (RS) can detect T-cell activation with high sensitivity. In this study we explore its specificity. Seventy-five inactivated, 40 alloantigen-activated, and 75 CD3/CD28-activated T cells were analyzed using RS. CD3/CD28-activated peak magnitudes (PM) were 4.3% to 23.9% lower than inactivated PM at positions: 903, 1031, 1069, 1093, 1155, 1326, and 1449 cm(-1), with a difference in peak ratio (PR) observed at the 1182:1195 cm(-1) position (0.91 +/- 0.06 vs. 1.2 +/- 0.01, respectively: P = 0.006). Differences in CD3/CD28- and alloantigen-activated PM were observed at: 903, 1031, 1093, 1155, 1326, and 1449 cm(-1), with no PR differences at the 1182:1195 cm(-1) position (0.91 +/- 0.06 vs. 0.86 +/- 0.09: P = 0.8). Spectral signature separation of CD3/CD28-and alloantigen-activated groups was 100% specific and sensitive. We conclude that RS can differentiate T cells activated by different stimuli with high sensitivity and specificity.

Equivalent outcomes with primary and retransplantation in African-American deceased-donor renal allograft recipients

BACKGROUND

Graft survival following renal retransplantation has been inferior to that following primary allografting, particularly in African Americans (AAs) receiving deceased-donor (DD) kidneys.

METHODS

Among 166 AA DD renal allograft recipients transplanted from July 2001 through July 2007, we compared the outcomes of 26 (16%) receiving a second graft with those of 140 primary cases. All patients received either thymoglobulin (ATG) or an IL-2 receptor antagonist for induction, and were maintained on either tacrolimus or sirolimus + mycophenolate mofetil +/- prednisone.

RESULTS

When compared with primary transplants, regrafts received kidneys from older donors, were younger, more sensitized, more likely to receive ATG and to be maintained on prednisone, received more doses of ATG, and were less likely diabetic. There was no difference between primary and retransplant groups in overall patient or graft survival; incidence of acute rejection, CMV infection, BK nephropathy, or new-onset diabetes mellitus; and serum creatinine at 1 year.

CONCLUSION

AA renal allograft recipients can undergo a second DD transplant with intermediate-term outcomes comparable to that of a primary graft, despite the presence of multiple immunologic and non-immunologic high-risk factors, by extending the course of ATG induction and continuing prednisone therapy in the vast majority of cases.

Two-dose daclizumab induction in pediatric renal transplantation

DCZ, an IL-2 receptor antagonist, has been widely used for induction therapy in pediatric and adult solid organ transplantation. Originally, it was recommended as a five-dose regimen; however, fewer doses may be efficacious and less costly for prevention of rejection. There is limited experience with the use of fewer doses in pediatric renal transplantation. We retrospectively reviewed the outcomes of 26 primary pediatric renal transplants performed at a single center between June 2004 and May 2007 receiving induction therapy with two-dose DCZ (1.5 mg/kg preoperatively and day seven post-transplant). Maintenance immunosuppression included tacrolimus, MMF, and prednisone in all patients. Forty-six percent were African American and 92% were deceased-donor transplants. After a mean follow-up of 17.8 +/- 7.5 months, acute rejection was noted in 11.5% and graft survival was 92.3%. CMV infection occurred in 11.5%, but no case of BK nephropathy or post-transplant lymphoproliferative disorder was observed. Our preliminary results suggest that induction therapy with two-dose DCZ was convenient, economical, and effective in preventing rejection episodes without an increase in adverse events or hospital stay. Larger randomized clinical trials with longer duration of follow-up are needed to more fully validate the use of this regimen in pediatric renal transplantation.

Ogilvie syndrome and herpes zoster: case report and review of the literature

BACKGROUND

The very unusual association between herpes zoster and Ogilvie syndrome has received scant attention in the published literature.

OBJECTIVES

This review discusses the published experience since 1950 and attempts to increase clinical awareness about the co-existence of both conditions.

CASE REPORT

An 84-year-old male patient affected by herpes zoster presented with advanced acute colonic pseudo-obstruction and was successfully treated with colonic diversion.

DISCUSSION

Twenty published studies (1950-2008) of 28 patients in whom the two conditions co-existed are reviewed. The review included 22 male and 7 female patients (24%) aged 32-87 years (mean, 61 years). Significant co-morbidities were present in 45% of the patients. The majority of patients were observed and treated conservatively (83%). Two patients died (7%), both suffering from respiratory complications and malignancy.

CONCLUSION

Recognition of the combined syndrome may help to avoid unnecessary surgery. Laparotomy should be reserved as a last resort for when the obstruction cannot be successfully managed by endoscopy. A diverting colostomy can be used to monitor the blood supply and thus provide early warning for an impending abdominal catastrophe.

Raman spectroscopic differentiation of activated versus non-activated T lymphocytes: an in vitro study of an acute allograft rejection model

Acute rejection (AR) remains a significant complication in renal transplant patients. Using serum creatinine for AR screening has proven problematic, and thus a noninvasive, highly sensitive and specific test is needed. T cells from human peripheral blood were analyzed using Raman spectroscopy. Fifty-one Mixed Lymphocyte Culture (MLC) activated T cells (ATC), 28 Mitomycin C inactivated T cells (ITC), and 35 resting T cells (RTC), were studied utilizing 785 and 514.5 nm wavelengths. Statistical analysis following subtraction of fluorescence used Student's t test to quantify peak ratio differences and discriminant function analysis (DFA), with three distinct sectors assigned for grouping purposes: Sector I, ITC; Sector II, ATC; Sector III, RTC. Differences between ATC and non-activated T cells (ITC and RTC) were found at 1182 and 1195 cm-1 peak positions for both wavelengths. Significant differences in peak ratios for 785 and 514.5 nm wavelengths existed between ATC and RTC (p=0.001 and p=0.006, respectively) and ATC and ITC (p=0.001 and p=0.001, respectively), with a trend in differences observed between ITC and RTC (p=0.07 and p=0.08, respectively). Analysis of the DFA-derived sector distribution for the 785 and 514.5 nm wavelengths revealed a sensitivity of 95.7% and 89.3%, respectively, and a specificity of 100% and 93.8%, respectively. This data suggests that Raman spectroscopy can detect significant differences between activated and nonactivated T cells based upon cell-surface receptor expression, thereby establishing unique signatures that can aid in the development of a noninvasive AR screening tool with high sensitivity and specificity.

Single wire versus double wire loops for median sternotomy closure: experimental biomechanical study using a human cadaveric model

BACKGROUND

Healing of median sternotomy requires reliable sternal fixation. Although both single and double wire kits are commercially available, no experimental study has compared the two closures in a human cadaveric model. We used a recently described human experimental cadaveric model to compare the stability of the closures.

METHODS

Sixteen fresh adult human cadaveric sternal plates with adjacent ribs were fixed with custom designed spiked stainless steel clamps and attached to a biomechanical testing device. Single No. 5 peristernal and double peristernal closures were tested. The stability of the unions was tested using perpendicular, repetitive force loads increasing from 0 to 800 Newtons at a rate of 0.5 mm/second.

RESULTS

The two study groups did not differ in age or sex. No clamp failures or damage to the specimens occurred. The double peristernal closure exhibited a significantly lower permanent displacement than the single wire group, suggesting a superior strength and stability of that closure.

CONCLUSIONS

To the extent to which this human cadaveric model resembles in vivo median sternotomy, these data suggest that the biomechanical stability of the peristernal double wire closure may exceed that of single wires.

Intermediate-term outcomes with early steroid withdrawal in African-American renal transplant recipients undergoing surveillance biopsy

BACKGROUND

There is a paucity of data regarding the use of early corticosteroid withdrawal (ESW) in African-American renal allograft recipients, and very few reports with >or=1 year follow-up in all patients.

METHODS

We examined the outcomes of 57 African-American renal allograft recipients with minimum follow-up 12 months who did not receive maintenance steroids after day 4 posttransplant. All patients received thymoglobulin induction, mycophenolate mofetil, and initial tacrolimus (n = 48) or sirolimus (n = 9).

RESULTS

Patient and graft survival were 98% and 96% at 1 year, and 95% and 89% over the entire follow-up period (mean, 23 +/- 8 months). Incidence of acute rejection and cytomegalovirus infection were 18% and 7%, respectively, with mean serum creatinine 1.6 +/- 0.5 and 1.7 +/- 0.9 mg/dL at 6 and 12 months. Of patients with functioning grafts, 84% remained steroid free at 1 year, of which 11 (24%) were also calcineurin inhibitor free. Twenty-seven patients underwent surveillance biopsy at 1 month and 28 at 12 months, with 15 surveyed at both time points. There were significant increases in only 2 of the 6 1997 Banff chronic allograft nephropathy (CAN) category scores in this subgroup, with all mean values remaining <1 (mild in severity) at 1 year. Overall, from 82% to 96% of the 12-month scores were <or=1 in all categories for 28 patients; only 3 patients (11%) had interstitial fibrosis and tubular atrophy scores at least moderate in severity. We did not observe any cases of subclinical acute rejection.

CONCLUSIONS

Our findings suggest that ESW in African-American renal allograft recipients with multiple high-risk factors can produce excellent intermediate-term antirejection and graft functional outcomes with minimal development of CAN at 12 months. Our results will need to be verified in larger numbers of patients with longer follow-up.

Subxiphoid incisional hernias after median sternotomy

BACKGROUND

Subxiphoid incisional hernias are notoriously difficult to repair and are prone to recurrence. The few reports on subxiphoid hernia published over the last two decades have not fully addressed the etiology, pathology, treatment, and outcome of this problem. This review was performed to analyze the published experience and increase the understanding of these difficult hernias.

METHODS

We reviewed the extensive literature, including the Medline and Current Contents computerized database searches, and searched the available bibliographies.

RESULTS

Seven retrospective studies of a total of 113 patients who had clinical subxiphoid hernias after median sternotomy were found. An additional surgical technique describing a modified median sternotomy preventing the hernia, and a single review article on selected technical considerations of subxiphoid ventral repair were also found.

CONCLUSIONS

The incidence of subxiphoid hernia after median sternotomy can be possibly reduced by paraxiphoid extension of the sternotomy, reinforcement near the xiphoid end of the incision, or by optimizing closure of the distal sternotomy and the linea alba. Abdominal wall reinforcement by open-mesh closure or laparoscopic transperitoneal prosthetic repair can effectively deal with the defect. Long-term outcome analyses are not yet available.

Sirolimus exposure during the early post-transplant period reduces the risk of CMV infection relative to tacrolimus in renal allograft recipients

INTRODUCTION

There are limited data regarding the role of individual maintenance immunosuppressive agents in the development of cytomegalovirus (CMV) infection. We examined the association between exposure to sirolimus (SRL) and risk of CMV infection after kidney transplantation when compared with tacrolimus (TCL).

METHODS

This is a retrospective observational study of adult renal allograft recipients transplanted between 2001 and 2005 at our center. Patients received anti-lymphocyte antibody induction, and mycophenolate mofetil with either SRL or TCL +/- prednisone. D+/R- patients received valganciclovir 900 mg/d and CMV + patients 450 mg/d for three months. CMV infection was diagnosed with pp65 antigenemia testing prompted by clinical suspicion.

RESULTS

A total of 14 Cases with CMV infection and 129 Controls were identified for primary analysis, and 11 D+/R- Cases and 19 D+/R- Controls for secondary analysis. The groups were comparable in both analyses, except for D+/R- serostatus in the primary analysis. All 14 Cases were on TCL for at least three months prior to diagnosis of CMV infection. In the primary analysis, zero Cases, but 30.2% and 34.9% of Controls (p = 0.009 and 0.004), and in secondary analysis, zero Cases, but 31.6% and 42.1% of Controls (p = 0.046 and 0.013), were on SRL at one and three months, respectively. In the primary analysis, zero Cases vs. 45 Controls (p = 0.004), and in secondary analysis, zero Cases vs. eight Controls (p = 0.013), were on SRL for at least three months early post-transplantation.

CONCLUSION

These findings suggest that SRL as a component of a multidrug immunosuppressive regimen decreases the risk of CMV infection after kidney transplantation when compared with TCL.

Depletion of the catalytic subunit of protein phosphatase-2A (PP2Ac) markedly attenuates glucose-stimulated insulin secretion in pancreatic beta-cells

Among various phosphatases, the protein phosphatase 2A (PP2A) is relatively well studied in the islet. Previously, we have demonstrated that the catalytic subunit of PP2A (PP2Ac) undergoes okadaic acid (OKA)-sensitive, reversible carboxylmethylation (CML), which appears to be requisite for glucose-stimulated insulin secretion (GSIS). Using the siRNA approach, we examined, herein, the contributory roles of PP2Ac in GSIS from insulin-secreting pancreatic beta-(INS-1 832/13) cells. Immunologically, PP2Ac was detectable in all the subcellular fractions studied in rank order of: cytosol > microsomes > secretory granules = nucleus > mitochondria. Transfection of PP2Ac-specific, but not scrambled-siRNA, markedly attenuated PP2A activity and GSIS in these cells. Together, our findings provide a direct evidence for a positive modulatory role for PP2Ac in signaling steps leading to GSIS.

Preliminary experience with cinacalcet use in persistent secondary hyperparathyroidism after kidney transplantation

BACKGROUND

There is limited experience with the use of cinacalcet in the treatment of persistent secondary hyperparathyroidism after kidney transplantation.

METHODS

We retrospectively analyzed our experience in 18 renal allograft recipients who initiated cinacalcet therapy from 1 month to 23 years (median 3 years) posttransplantation and were maintained on the drug for 6 months. The daily dose was titrated from 30 mg up to a maximum of 180 mg to achieve a reduction in serum intact parathyroid hormone (PTH) levels.

RESULTS

Sustainable, significant decreases in mean calcium and alkaline phosphatase were noted at 1 month and intact PTH by 3 months, with 50% of patients achieving at least a 30% drop in PTH levels at 6 months. Serum phosphorous increased at 6 months, whereas urine N-telopeptides decreased. There were no significant changes in serum osteocalcin, albumin, and hemoglobin levels. We did not observe a tachyphylaxis phenomenon. Two patients reported occasional nausea, but did not require medication discontinuation. Estimated glomerular filtration rate did decrease progressively over the 6-month period.

CONCLUSION

Cinacalcet appears to be an effective drug for the treatment of posttransplant hypercalcemia due to persistent secondary hyperparathyroidism. Further studies with more patients and longer follow-up will be needed to better elucidate the efficacy/safety profile for this agent, particularly with regard to long-term bone histology and renal outcomes.

Intravenous immunoglobulin, HLA allele typing and HLAMatchmaker facilitate successful transplantation in highly sensitized pediatric renal allograft recipients

The use of intravenous immunoglobulin (IVIG) in sensitized transplant candidates has resulted in reduced HLA antibody levels and shorter transplant wait times. In addition, the HLAMatchmaker program has been used to identify acceptable mismatches to permit transplantation in highly sensitized patients. We used IVIG desensitization in conjunction with high resolution HLA allele typing and HLAMatchmaker grading of donor offers to facilitate successful transplantation in two highly sensitized children who were awaiting second renal transplants. Both patients lost their initial transplant in <10 days to accelerated acute rejection, and were on dialysis for an average of 50 months with high panel reactive antibody (PRA) levels. They were started on monthly IVIG infusions (2 g/kg/dose). Within one wk following their third and fifth IVIG doses, both patients received a crossmatch compatible, deceased donor renal transplant selected by HLAMatchmaker as a suitable donor offer. Both patients remain rejection free with excellent renal function 19 and 15 months post-transplant, respectively. In conclusion, combining IVIG therapy and donor selection by HLA humoral epitope matching permitted successful transplantation of two highly sensitized children. Further studies in larger numbers of patients with longer follow-up are needed to determine the individual role played by, and relative importance of each component of this combined strategy.

Infectious complications after kidney transplantation: current epidemiology and associated risk factors

BACKGROUND

The impact of newer immunosuppressive and antimicrobial prophylactic agents on the pattern of infectious complications following kidney transplantation has not been well studied.

METHODS

This is an observational study in 127 adult recipients transplanted from 2001 to 2004. Patients received thymoglobulin (ATG) (50%) or basiliximab (50%) for induction and were maintained on mycophenolate mofetil, either tacrolimus (73%) or sirolimus (SRL) (27%), and prednisone (79%). Antimicrobial prophylaxis included perioperative cefazolin, trimethoprim/sulfamethaxazole for six months, valganciclovir for three months and nystatin for two months. Regression models were used to examine the association of various factors with infections.

RESULTS

We observed 127 infections in 65 patients, consisting of urinary tract infection (UTI) (47%), viral infections (17%), pneumonia (8%) and surgical wound infections (7%). UTI was the most common infection in all post-transplant periods. Enterococcus spp. (33%) and Escherichia coli (21%) were the most prevalent uropathogens. Of six patients with cytomegalovirus infection, none had tissue-invasive disease. There were no cases of pneumocystis pneumonia or BK nephropathy. Six patients developed fungal infections. Two deaths due to disseminated Rhizopus and Candida albicans accounted for a 1.5% infection-related mortality. Retransplantation and ureteral stents were independently associated with UTI (OR=4.5 and 2.9, p=0.06 and 0.03, respectively), as were ATG and SRL with bacterial infections (OR=3.3 and 2.5, p=0.009 and 0.047, respectively).

CONCLUSION

This study suggests that the use of newer immunosuppressive agents in recent years is associated with some changes in the epidemiology of post-transplant infections. Enterococci have become the predominant uropathogen. Invasive fungal infections, although rare, are often fatal.

Short-term experience with early steroid withdrawal in African-American renal transplant recipients

There are limited data on the results of early steroid withdrawal (ESW) in African-American (AA) renal allograft recipients. We examined short-term transplant outcomes in a retrospective, non-concurrent cohort study of 40 AAs who did not (ESW group), and 33 who did [steroid maintenance (SM) group] receive maintenance steroids after day 4 post-transplant. Patients received thymoglobulin (ATG) induction, mycophenolate mofetil, and tacrolimus or sirolimus. Data were analyzed using survival analysis methods and regression models. Patients in the ESW group were older, had lower current panel reactive antibody and fewer re-transplants, and received fewer doses of ATG. One-year graft survival and acute rejection (AR) rates were 100% and 13% in the ESW group and 97% and 15% in the SM group. After controlling for confounders, at 1 year, ESW was not associated with higher risk of graft loss, AR, or worse graft function, but was associated with less weight gain. The SM group had higher cholesterol levels at 3 months and higher risk of post-transplant diabetes mellitus. We did not observe any cases of subclinical rejection. This study suggests that ESW under modern immunosuppression is safe over the short term in at least a subset of AA recipients with risk profiles similar to those studied herein, and could be associated with improved outcomes.

Early pancreas transplant outcomes with histidine-tryptophan-ketoglutarate preservation: a multicenter study

Little is known about the use of histidine-tryptophan-ketoglutarate (HTK) preservation solution for pancreas preservation. We compared early pancreas graft outcomes at four pancreas transplant programs within the state of Michigan in 2002 and 2003 (University of Wisconsin [UW] era) with those in 2004 (HTK era). The primary endpoint was early graft loss. The UW group (n=41) and the HTK group (n=36) had similar outcomes with respect to: technical graft loss (9.8% vs. 8.3%, P=NS), 90-day graft function (90.2% vs. 86.1%, P=NS), and rate of pancreatic leak/abscess (12.2% vs. 11.1%, P=NS). There were also no significant differences in postoperative amylase and lipase levels between the two groups. The HTK group did have significantly more acute rejection within the first 180 days (25.0% vs. 9.8%, P<0.05). HTK is a suitable substitute for UW in the preservation of pancreas allografts.