Wound healing adverse events in kidney transplant recipients receiving everolimus with reduced calcineurin inhibitor exposure or current standard-of-care: insights from the 24-month TRANSFORM study

OBJECTIVES

In TRANSFORM, de novo kidney transplant recipients received either everolimus in combination with reduced-exposure calcineurin inhibitor (EVR+rCNI) at standard EVR pre-dose concentrations of 3-8 ng/mL or mycophenolic acid plus standard-exposure CNI (MPA+sCNI). The authors analyzed the incidence of wound healing adverse events (WHAEs) over the 2-year study period 15.

METHODS

Patients were randomized to either EVR+rCNI or MPA+sCNI, both combined with induction therapy and steroids 19.

RESULTS

The safety population consisted of 2,026 patients (EVR+rCNI: 1,014, MPA+sCNI: 1,012). The proportion of patients with at least 1 WHAE was comparable between EVR+rCNI and MPA+sCNI treatment groups [20.6% vs. 17.3%; risk ratio (RR): 1.19; 95% confidence interval (CI): 0.99, 1.43] at month 24. The numerical difference between EVR+rCNI and MPA+sCNI was mainly caused by an increased proportion of EVR patients with lymphocele and wound dehiscence [7.5% vs. 5.1% (RR: 1.46; 95% CI: 1.04, 2.05) and 3.9% vs. 1.8% (RR: 2.22; 95%CI: 1.28, 3.84), respectively] 20.

CONCLUSION

The immediate introduction of EVR+rCNI after kidney transplantation was associated with an overall comparable incidence of WHAEs versus current standard-of-care over the 24-month study period. There was an increased relative risk of experiencing lymphocele and wound dehiscence but the absolute risks were rather low in both groups 21.

CT.GOV IDENTIFIER

NCT01950819.

Novel colchicine derivatives enhance graft survival after transplantation via suppression of T-cell differentiation and activity

Immunosuppressants are crucial in organ transplantation but their side effects are a trade-off for long-term use. Colchicine has been shown to be effective in various diseases, albeit with many side effects. To enhance the immunosuppressive effects of colchicine, in addition to minimizing its side effects, we attempted to synthesize new colchicine derivatives (KR compounds). In rat cardiac and pancreatic islet allograft, long-term graft survival was identified in KR compound-treated groups. The use of cyclosporine A (CsA) or colchicine inhibited the CD3⁺ and CD4⁺ T-cell proliferation, whereas KR compounds inhibited the CD8⁺ T cells as well as CD4⁺ T cells. KR compounds reduced the apoptosis, interleukin-2 receptor expression, and signal transducer and activator of transcription 3 phosphorylation more than CsA. These results indicate that KR compounds have a potential therapeutic value as novel agents for prevention of graft deterioration by allograft of rejection.

Real Renal Function After Renal Autotransplantation Through the Analysis of Solitary Kidney Autotransplantation Cases

INTRODUCTION

Previous studies of the safety of renal autotransplantation (RAT) have been limited by a lack of evidence. Because of the influence of the opposite kidney, it is difficult to evaluate actual renal function. This study evaluated the actual results of RAT by collecting only cases involving a solitary kidney.

METHODS

Between September 1, 1999, and November 30, 2015, 9 RAT procedures were performed in 9 patients with a solitary kidney. We retrospectively evaluated medical data collected prospectively. Renal function was evaluated using the creatinine level and the estimated glomerular filtration rate (eGFR).

RESULTS

The indications for RAT differed among the nin9e study patients. Five patients had complex renovascular problems, 2 were treated for partial nephrectomy, 1 was had a radically resected ureter due to ureteral cancer, 1 patient underwent RAT for the preservation of renal function during suprarenal-type abdominal aortic aneurysm repair. The mean cold ischemic time was 116.66 minutes (range, 21-256), and the mean follow-up duration was 54.2 months (range, 1 to 184). There were no significant decreases in eGFR until 12 months except 1 patient who underwent RAT with partial nephrectomy due to renal cell cancer.

CONCLUSIONS

We report stable renal function after RAT in patients with solitary kidney. Postoperative complications were rare. This is evidence for the safety of RAT.

Clinical applications of interferon-γ releasing assays for cytomegalovirus to differentiate cytomegalovirus disease from bystander activation: a pilot proof-of-concept study

BACKGROUND/AIMS

We evaluated the proposed clinical application of the combined interpretation of host factors and viral factors in two different cytomegalovirus (CMV) co-infection models.

METHODS

We prospectively enrolled all human immunodeficiency virus non-infected patients with confirmed Pneumocystitis jirovecii pneumonia (PCP) and those with suspected gastrointestinal CMV disease in a tertiary hospital. All patients underwent CMV interferon-γ releasing assay (IGRA) for CMV (T-track CMV, Lophius Biosciences). We created the 2-axis model with the CMV IGRA results as the x-axis and the results for CMV virus replication as the y-axis, and hypothesized that cases falling in the left upper quadrant (high viral load and low CMV-specific immunity) of the model would be true CMV infections. The CMV IGRA results were concealed from the attending physicians.

RESULTS

Of 39 patients with PCP, four (10%) were classified as combined CMV pneumonia, 13 (33%) as bystander activation, and the remaining 22 (56%) as no CMV infection. The data for all four patients with PCP and CMV pneumonia fell in the left upper quadrant of the 2-axis model. Of 24 patients with suspected gastrointestinal CMV disease, 12 (50%) were classified as gastrointestinal CMV disease and the remaining 12 (50%) as bystander activation with no gastrointestinal CMV disease. The data for 11 of the 12 patients (92%) with gastrointestinal CMV disease were located in the left upper quadrant of the 2-axis model.

CONCLUSIONS

Cases yielding low CMV IGRA results and high CMV viral replication appear to be true CMV infections. Further studies with large number of cases in different types of CMV disease should be proposed.

Four-Year Experience With Extracorporeal Membrane Oxygenation for Kidney Transplant Patients With Severe Refractory Cardiopulmonary Insufficiency

BACKGROUND

Kidney transplant (KT) recipients are vulnerable to infections because of their immunosuppressive treatments, and they occasionally exhibit serious acute cardiopulmonary dysfunction. The purpose of this study was to report the clinical outcomes of using extracorporeal membrane oxygenation (ECMO) in KT recipients and to identify risk factors for ECMO weaning failure.

METHODS

We retrospectively reviewed the electronic medical records of KT patients who experienced severe cardiopulmonary dysfunction refractory to conventional therapy and received ECMO at the Asan Medical Center Surgical Intensive Care Unit between December 2010 and December 2014.

RESULTS

During the 4-year study period, 12 KT patients required ECMO management. Six of these patients were successfully weaned from ECMO; the mean duration of ECMO support was 9.1 days (range, 3.5-15.1 days). Indications for ECMO included pneumonia (8 cases required venovenous ECMO and 1 case required venoarterial [VA] ECMO), stress-induced cardiomyopathy due to fungemia (1 case required VA ECMO), and septic shock due to either urinary tract infection or unknown origin (2 cases required VA ECMO). In assessing risk factors leading to a failure of ECMO weaning, the pH on arterial blood gas analysis performed just before the beginning of this intervention was significantly lower in the nonsurvivors than in the survivors (P = .046).

CONCLUSIONS

ECMO can be a beneficial rescue therapy in immunosuppressed patients with cardiopulmonary dysfunction refractory to treatment. Severe acidosis before the administration of EMCO is a major determinant of ECMO weaning failure.

Protective Effect of Polydeoxyribonucleotide Against Renal Ischemia-Reperfusion Injury in Mice

BACKGROUND

Polydeoxyribonucleotide (PDRN) is an A2A receptor agonist that induces vascular endothelial growth factor (VEGF) production during the pathological condition of low tissue perfusion. Ischemia-reperfusion injury (IRI) is a major problem after renal transplantation. In the present study, we investigated whether PDRN exhibits reno-protective effects against ischemia-reperfusion-induced acute kidney injury in mice.

METHODS

Renal ischemia-reperfusion injury was induced in male C57BL/6 mice by bilateral renal pedicle occlusion for 30 minutes, followed by reperfusion for 48 hours. PDRN (8 mg/kg body weight intraperitoneally) was administered 30 minutes before IRI.

RESULTS

Treatment with PDRN significantly decreased neutrophil gelatinase-associated lipocalin levels in the urine, blood urea nitrogen level, and serum creatinine levels as well as kidney tubular injury. Western blotting showed that PDRN significantly increased the levels of vascular endothelial growth factor and B-cell lymphoma protein and attenuated p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, inducible nitric oxide synthase, and Bcl-2-associated X protein levels 48 hours after IRI.

CONCLUSIONS

Our findings suggest that PDRN is a potential therapeutic agent for acute ischemia-induced renal damage.

Red Ginseng Administration Before Islet Isolation Attenuates Apoptosis and Improves Islet Function and Transplant Outcome in a Syngeneic Mouse Marginal Islet Mass Model

BACKGROUND

Transplantation of isolated islets is a promising treatment for diabetes. Red ginseng (RG) is steamed ginseng and has been reported to enhance insulin secretion-stimulating and anti-apoptotic activities in pancreatic β-cells. In this study, we examined the hypothesis that pre-operative RG treatment enhances islet cell function and anti-apoptosis and investigated whether RG improves islet engraftment by transplant of a marginal mass of syngeneic islets pretreated with RG in diabetic mice.

METHODS

Balb/c mice were randomly divided into 2 groups, and 1 group was administered RG (400 mg/kg/day orally) for 7 days before islet isolation. In vitro islet viability and function were assessed. After cytokine treatment, cell viability, function, and apoptosis of islet cells were analyzed. Furthermore, we studied the effects of RG in a syngeneic islet graft model. A marginal mass of syngeneic mouse islets was transplanted into diabetic hosts.

RESULTS

Islet pretreatment with RG showed 1.4-fold higher glucose-induced insulin secretion than did control islets. RG pretreatment upregulated B-cell lymphoma 2 (Bcl-2) expression and downregulated Bcl-associated X protein (BAX), caspase-3, and inducible nitric oxide synthase (iNOS) expression. Glucose-induced insulin release, NO, and apoptosis were significantly improved in RG-pretreated islets compared with cytokine-treated islets. RG-pretreated mice exhibited improved marginal mass islet graft survival compared with controls.

CONCLUSIONS

These results suggest that pre-operative RG administration enhanced islet function before transplantation and attenuated cytokine-induced damage associated with apoptosis. These studies indicate that inhibition of apoptosis by RG significantly improved islet cell and graft function after isolation and transplantation, respectively.

Incidence and differential characteristics of culture-negative fever following pancreas transplantation with anti-thymocyte globulin induction

BACKGROUND

Limited data are available on the incidence and characteristics of culture-negative fever following pancreas transplantation (PTx) with anti-thymocyte globulin (ATG) induction. Our study aims to better define the features of culture-negative fever, so it can be delineated from infectious fever, hopefully helping clinicians to guide antibiotic therapy in this high-risk patient population.

METHODS

We performed a retrospective cohort study of postoperative fever among 198 consecutive patients undergoing PTx at our center between August 1, 2004 and December 31, 2014. Fever was classified as culture-negative if there was neither a positive culture nor a documented clinical diagnosis of infection.

RESULTS

Fever was identified in 113 patients; 66 were deemed to be infectious, 39 were culture-negative, and 8 were indeterminate. High body mass index of recipient (odds ratio 1.87, 95% confidence interval: 1.15-3.03, P = 0.011) was a significant factor associated with culture-negative fever in multivariate analysis. No patients with culture-negative fever were diagnosed with infiltrates or effusion on chest radiography. In addition, an increase in white blood cell count, C-reactive protein, and serum amylase was less prominent in culture-negative fever. Culture-negative fever developed most frequently at postoperative 7 or 14 days, showing a biphasic curve.

CONCLUSION

Culture-negative fever develops in a substantial proportion of patients early after PTx. The awareness of the possibility and clinical features of post-transplant culture-negative fever might help clinicians to guide antibiotic therapy in this high-risk patient population, especially following ATG induction and early steroid withdrawal.

Pancreas Transplantation From Living Donors: A Single Center Experience of 20 Cases

Living donor pancreas transplantation (LDPT) has several advantages over deceased donor pancreas transplantation (DDPT), including better HLA matching, shorter ischemic time, and shorter waiting time. It remains an attractive option for diabetes mellitus (DM) patients with end stage renal disease. We reviewed 20 cases of LDPT performed in Asan Medical Center between October 1992 and March 2015. Six cases (30%) were pancreas transplantation alone (PTA), and the rest (70%) were simultaneous pancreas and kidney transplantation (SPK). Relations of donor and recipient were parents in 7 (35%), siblings in 6 (30%), spouse in 6 (30%), and cousin in 1 (5%). Graft survival in SPK at 1, 3, 5, and 10 years was 91.7%, 83.3%, 83.3%, and 83.3%, respectively, and that in PTA recipients was 50%, 33.3%, 16.7%, and 16.7%, respectively (p = 0.005). Causes of graft failure in SPK were thrombosis (one case), and rejection (one case), whereas those in PTA were noncompliance (two cases), thrombosis (one case), reflux pancreatitis (one case), and chronic rejection (one case). In terms of pancreas exocrine drainage, two grafts (25%) maintained their function in bladder drainage, while all grafts maintained in enteric drainage p < 0.05). Seven (35%) donors experienced minor pancreatic juice leakage and one underwent reoperation due to postoperative hematoma. Most donors maintained normoglycemia and normal renal function. However, two donors developed DM (at 1 and 90 months postdonation), and were treated with oral hypoglycemic agents. Graft survival in PTA recipients was poorer than in SPK due to poor compliance and bladder drainage-related problems. The surgical and metabolic complication rates of donors can be minimized by applying strict donor criteria. Therefore, LDPT with enteric drainage is an acceptable treatment for SPK.

Involvement of indirectly allostimulated CD4+CD43highCD45RO+ T cell proliferation in the development of chronic allograft nephropathy

The goal of this study was to identify immunological markers for use in antigen-specific assays that predict long-term survival after renal allograft and distinguish stable-functioning (SP) patients from poorly functioning (PP) patients. For this prospective study, 20 patients were enrolled. Eight SP and six PP patients were enrolled in this study. Serum cytokine/chemokine levels were analyzed by the Luminex multiplex assay. To detect indirect alloreactive T cells, we performed indirect mixed lymphocyte reaction using donor-antigen-pulsed autologous dendritic cells as stimulators. Serum induced protein-10 levels were significantly higher in the serum of PP patients, whereas sCD40L levels were higher in SP patients. The PP patients had significantly higher numbers of donor-specific CD4(+)CD43(high)CD45RO(+) T cells after indirect allostimulation, whereas this cell population was unchanged in SP patients. The donor-specific CD4(+)CD43(high)CD45RO(+) T cells had the effector memory T cell phenotype. Prospectively, we studied whether these cells influence graft outcome and found that their strong proliferation in pre-transplant patients is related to a poorly functioning graft. Indirectly allostimulated CD4(+)CD43(high)CD45RO(+) T cells may not only contribute to chronic allograft nephropathy development but may also have a role in the progression of acute rejection. Thus, these cells may have potential use as immune-monitoring markers in a noninvasive in vitro assay that predicts graft outcome.

Posttransplant Hyponatremia Predicts Graft Failure and Mortality in Kidney Transplantation Recipients: A Multicenter Cohort Study in Korea

Although hyponatremia is related to poorer outcomes in several clinical settings, its significance remains unresolved in kidney transplantation. Data on 1,786 patients who received kidney transplantations between January 2000 and December 2011 were analyzed. The patients were divided into two groups according to the corrected sodium values for serum glucose 3 months after their transplantations (<135 mmol/L vs. ≥135 mmol/L). Subsequently, the hazard ratios (HRs) for biopsy-proven acute rejection, graft failure, and all-cause mortality were calculated after adjustments for several immunological and non-immunological covariates. 4.0% of patients had hyponatremia. Patients with hyponatremia had higher risks for graft failure and all-cause mortality than did the counterpart normonatremia group; the adjusted HRs for graft failure and mortality were 3.21 (1.47-6.99) and 3.03 (1.21-7.54), respectively. These relationships remained consistent irrespective of heart function. However, hyponatremia was not associated with the risk of acute rejection. The present study addressed the association between hyponatremia and graft and patient outcomes in kidney transplant recipients. Based on the study results, our recommendation is to monitor serum sodium levels after kidney transplantations.

How to reduce lethal infectious complications in ABO-incompatible kidney transplantation

BACKGROUND

ABO-incompatible organ transplants are good options for expanding the living donor pool; however, the necessary pre-conditioning to remove ABO antibodies before surgery can evoke critical infectious complications after surgery.

METHODS

Between February 2009 and July 2013, we performed ABO-incompatible kidney transplantation on 182 patients. We analyzed the first 85 patients for post-operative infectious complications in a cross-sectional cohort of patients (group 1, n = 85) who had received an ABO-incompatible kidney transplant and, in light of the results, amended the pre-conditioning (lower dose of rituximab, selective use of calcineurin inhibitors, anti-metabolite reduction, and prophylactic strategy) given to a prospective cohort (group 2, n = 97).

RESULTS

The characteristics of the two groups did not differ significantly. Infectious complications decreased significantly in group 2, including cytomegalovirus (anti-genemia 64.7% vs 27.8%, P < .001) and BK viremia (35.2% vs 18.6%, P = .008). The acute rejection rate and death-censored graft survival were similar in both groups. Notably, with the modified protocol, there were no deaths (8.2% vs 0.0%, P = .03).

CONCLUSIONS

Pre-conditioning for ABO-incompatible kidney transplantation is a prerequisite for successful outcome; its drawbacks can be limited with the use of a modified immunosuppressive strategy. If immunosuppression is modified according to host conditions, ABO-incompatible kidney transplantation can be performed safely with a successful graft outcome.

The reciprocal interaction between LV remodelling and allograft outcomes in kidney transplant recipients

OBJECTIVE

This study aimed to investigate the incidence and related clinical factors of LV hypertrophy (LVH) regression after kidney transplantation and its effect on graft outcome.

METHODS

Among the 3373 kidney transplant recipients who were enrolled in a multicentre cohort from 1997 to 2012, a total of 767 patients who underwent echocardiography before and after transplantation were included in this study followed for a median of 7.5 years.

RESULTS

LVH regression steadily increased from 7.4% at 1 year to 35.4% at 5 year over the 5-year post-transplantation period. The probability of LVH regression decreased in the patients who received a kidney transplant due to end-stage renal disease of unknown aetiology (p=0.041) or who underwent pretransplant haemodialysis (p=0.020). The probability of LVH regression also decreased as the pretransplant LV mass index (p<0.001) and post-transplant systolic blood pressure increased (p=0.005). Conversely, LVH regression was significantly associated with the highest tertile of the pretransplant haemoglobin level (p=0.029). Furthermore, in the 5th year after transplantation, persistent LVH was independently associated with allograft failure (HR 1.95; 95% CI 1.14 to 3.33; p=0.015) and the LV mass index reliably predicted graft outcome.

CONCLUSIONS

LVH consistently regressed after kidney transplantation in most patients. Persistent LVH, low haemoglobin levels and elevated blood pressure were associated with an increased risk of allograft failure in kidney transplant recipients.

Observation of large group index enhancement in Doppler-broadened rubidium vapor

We report experimental observation of large group index across the Lamb dips of ground hyperfine states in Doppler-broadened 87Rb vapor. By sweeping the laser frequency through each hyperfine transition we measure the saturated absorption and optical phase shift using a phase-locked Mach-Zehnder interferometer. Our measurements provide a direct demonstration of the theoretical prediction by Agarwal et al. [G. S. Agarwal and T. N. Dey, Phys. Rev. A 68, 063816, (2003)] for the first time. An enhancement factor as large as 1005 in group index was observed for Rb vapor at temperature of 85 °C. The experimental data are in good agreement with the theory.

Pretransplant malnutrition, inflammation, and atherosclerosis affect cardiovascular outcomes after kidney transplantation

Background

Malnutrition, inflammation, and atherosclerosis (MIA) syndrome is associated with a high mortality rate in patients with end-stage renal disease. However, the clinical relevance of MIA syndrome in kidney transplantation (KT) recipients remains unknown.

Methods

We enrolled 1348 adult KT recipients. Recipients were assessed based on serum albumin, cholesterol, or body mass index for the malnutrition factor and C-reactive protein level for the inflammation factor. Any history of cardiovascular (CV), cerebrovascular, or peripheral vascular disease satisfied the atherosclerosis factor. Each MIA factors were assessed by univariate analysis and we calculated an overall risk score by summing up scores for each independent variable. The enrolled patients were divided into 4 groups depending on the MIA score (0, 2–4, 6, 8–10).

Results

The patients with higher MIA score showed worse outcome of fatal/non-fatal acute coronary syndrome (ACS) (p < 0.001) and composite outcomes of ACS and all-cause mortality (p < 0.001) than with the lower MIA score. In multivariate analysis, ACS showed significantly higher incidence in the MIA score 8-10 group than in the MIA score 0 group (Hazard ratio 6.12 95 % Confidence interval 1.84–20.32 p = 0.003).

Conclusions

The presence of MIA factors before KT is an independent predictor of post-transplant CV outcomes.

5,7-dihydroxy-3,4,6-trimethoxyflavone attenuates ischemic damage and apoptosis in mouse islets

BACKGROUND

The transplantation of isolated pancreatic islets is a promising treatment for diabetes. 5,7-dihydroxy-3,4,6-trimethoxyflavone (Eupatilin), a pharmacologically active flavone derived from the Artemisia plant species, has been reported to have antioxidant and anti-inflammatory activities. This study examines the hypothesis that preoperative eupatilin treatment can attenuate ischemic damage and apoptosis before islet transplantation.

METHODS

Islets isolated from Balb/c mice were randomly divided into 2 groups, and cultured in medium supplemented with or without eupatilin. In vitro islet viability and function were assessed. After treatment with a cytokine cocktail consisting of tumor necrosis factor (TNF)-α, interferon (INF)-γ, and interleukin (IL)-1β, islet cell viability, function, and apoptotic status were determined. The glutathione (GSH) and nitrous oxide (NO) levels were also measured. Proteins related to apoptosis were analyzed using Western blotting.

RESULTS

There was no difference in cell viability between the 2 groups. Islets cultured in the medium supplemented with eupatilin showed 1.4-fold higher glucose-induced insulin secretion than the islets cultured in the medium without eupatilin. After treatment with a cytokine cocktail, glucose-induced insulin release and the total insulin content of the islets were significantly improved in eupatilin-pretreated islets compared with islets not treated with eupatilin. Apoptosis was significantly decreased, and GSH levels were elevated in the eupatilin-pretreated group. Cytokine-only treated islets produced significantly higher levels of NO, iNOS, and caspase-3 than islets pretreated with eupatilin before cytokine treatment.

CONCLUSIONS

These results suggest that preoperative eupatilin administration enhances islet function before transplantation and attenuates the cytokine-induced damage associated with NO production and apoptosis.

Emerging Yr26-Virulent Races of Puccinia striiformis f. tritici Are Threatening Wheat Production in the Sichuan Basin, China

Stripe rust, caused by Puccinia striiformis f. tritici, is one of the most destructive diseases of wheat in the world. The Sichuan Basin is one of the most important regions of wheat production and stripe rust epidemics in China. Stripe rust resistance gene Yr26 (the same gene as Yr24) has been widely used in wheat breeding programs and in many cultivars grown in this region since the gene was discovered in the early 1990s. Virulence to Yr26 has increased in frequency since its first detection in 2008. The objective of this study was to assess the vulnerability of the wheat cultivars and breeding lines in the Sichuan Basin to Yr26-virulent races. In total, 85 wheat accessions were tested with Yr26-avirulent races CYR32, CYR33, and Su11-4 and two Yr26-virulent races, V26/CM42 and V26/Gui22. DNA markers for Yr26 were used to determine the presence and absence of Yr26 in the wheat accessions. Of the 85 wheat accessions, only 5 were resistant and 19 susceptible to all races tested, and the remaining 61 were resistant to at least one or more races tested in seedling stage. In all, 65 (76.5%) accessions were susceptible to the emerging Yr26-virulent race V26/Gui22. In field tests, susceptible accessions increased from 31.8% in a nursery inoculated with predominant and Yr26-avirulent races to 61.2% in the nursery inoculated with the predominant races mixed with V26/Gui22. Based on the results of the molecular marker and race tests, 33 (38.8%) accessions were determined to have Yr26, showing that the Yr26 virulence is a major threat to wheat production in the Sichuan Basin and potentially in other regions of China.

Ginsenoside Rg3 enhances islet cell function and attenuates apoptosis in mouse islets

BACKGROUND

The transplantation of isolated islets is thought to be an attractive approach for curative treatment of diabetes mellitus. Panax ginseng has been used in oriental countries for its pharmacologic effects, such as antidiabetic and antiinflammatory activities. 20(S)-ginsenoside Rg3 (Rg3), an active ingredient of ginseng saponins, has been reported to enhance insulin secretion-stimulating and antiapoptotic activities in pancreatic beta cells. We performed this study to examine the hypothesis that preoperative Rg3 administration can enhance islet cell function and antiapoptosis before islet transplantation.

METHODS

Balb/c mice were randomly divided into 2 groups according to the administration of Rg3 after islet isolation. Mouse islets were cultured in medium supplemented with or without Rg3. In vitro, islet viability and function were assessed. After treatment of islets with a cytokine cocktail (tumor necrosis factor α, interferon-γ, and interleukin-1β), cell viability, function, and apoptosis were assessed.

RESULTS

Cell viability was similar between the 2 groups. Islets cultured in medium supplemented with Rg3 showed 2.3-fold higher glucose-induced insulin secretion than islets cultured in medium without Rg3. After treatment with a cytokine cocktail, glucose-induced insulin release, total insulin content of islets, and apoptosis were significantly improved in Rg3-treated islets compared with cytokine-treated islets. Cytokine-treated islets produced significantly higher levels of nitric oxide (NO) than islets treated with Rg3.

CONCLUSIONS

These results suggest that preoperative Rg3 administration enhanced islet function before islet transplantation and attenuated both cytokine-induced damage associated with NO production and apoptosis. Rg3 administration might be a prospective management to enhanced islet function and ameliorate early inflammation after transplantation.

Characterization and molecular mapping of stripe rust resistance gene Yr61 in winter wheat cultivar Pindong 34

We report a new stripe rust resistance gene on chromosome 7AS in wheat and molecular markers useful for transferring it to other wheat genotypes. Several new races of the stripe rust pathogen have established throughout the wheat growing regions of China in recent years. These new races are virulent to most of the designated seedling resistance genes limiting the resistance sources. It is necessary to identify new genes for diversification and for pyramiding different resistance genes in order to achieve more durable resistance. We report here the identification of a new resistance gene, designated as Yr61, in Chinese wheat cultivar Pindong 34. A mapping population of 208 F2 plants and 128 derived F2:3 lines in a cross between Mingxian 169 and Pindong 34 was evaluated for seedling stripe rust response. A genetic map consisting of eight resistance gene analog polymorphism (RGAP), two sequence-tagged site (STS) and four simple sequence repeat (SSR) markers was constructed. Yr61 was located on the short arm of chromosome 7A and flanked by RGAP markers Xwgp5467 and Xwgp5765 about 1.9 and 3.9 cM in distance, which were successfully converted into STS markers STS5467 and STS5765b, respectively. The flanking STS markers could be used for marker-assisted selection of Yr61 in breeding programs.

Significance of isoagglutinin titer in ABO-incompatible kidney transplantation

ABO-incompatible (ABO-i) kidney transplantation (KT) has emerged for overcoming the shortage of organ donors. Although this technique initially achieved only low graft survival due to isoagglutinin, recently developed desensitization protocols have improved survival to levels that are comparable to ABO-compatible KT. However, isoagglutinin is still regarded as a major obstacle to ABO-i KT. In this study, we evaluate the impact of isoagglutinin titer on clinical outcomes as well as factors that may influence isoagglutinin titers. In total, data from 95 patients who underwent ABO-i KT were analyzed. Preoperatively, rituximab administration and plasmapheresis were performed until the titer was reduced to ≤1:4. Retrospective analysis included blood group; timing and dosage of rituximab; isoagglutinin titer; number of plasmapheresis; and clinical outcomes including graft survival and serum creatinine. Graft survival was 95.8% (n = 91) and average serum creatinine at 1- and 1.5-year post-ABOi-KT was 1.3. Three patients died of sepsis. The identified predictors of titer-rebound after transplant were short interval (<7 days) between rituximab and first plasmapheresis (P = 0.004); high initial titer (≥256) (P = 0.023); low titer-reduction rate (P < 0.001); and blood group O (P < 0.001). One patient who experienced a rebound developed antibody-mediated rejection. With low-dose (200 mg) rituximab, the change in isoagglutinin titer-rebound was not significant and the infection rate was significantly decreased (P = 0.001). In conclusion, isoagglutinin titer-rebound within the first 2 weeks after KT may be a risk factor for rejection. The factors identified as affecting titer-rebound after KT were high initial isoagglutinin titer, low titer-reduction rate, short interval, and blood group O.

A 39-month follow-up study to evaluate the safety and efficacy in kidney transplant recipients treated with modified-release tacrolimus (FK506E)-based immunosuppression regimen

BACKGROUND

We initially performed a study to evaluate the safety and efficacy of modified-release tacrolimus (FK506E) in a phase 3, 2-arm, 6-month, randomized, open-label, multicenter trial in Korean living donor de novo kidney transplant recipients. We then performed an extended study to evaluate the long-term safety and efficacy of a FK506E-based regimen up to 45 months posttransplantation in recipients already treated with FK506E.

METHODS

Initial study was designed as a randomized, open-label, comparative, multicenter study in de novo living donor kidney transplant recipients. The patients were randomized to an FK506E versus a control (FK506) group (1:1). Recipients who completed a 6-month FK506E treatment study were enrolled in the 39-month follow-up study. Primary end-points were patient and graft survivals at posttransplantation 45 months. Secondary end-point was the incidence of a clinical or biopsy-proven acute rejection episode between 6 and 45 months posttransplantation.

RESULTS

In the initial 6-month de novo study 124 enrolled patients were randomized into either the FK506E (n = 62) or the control group (n = 62). The incidence of an acute rejection episode was 19.4% (n = 12) in the FK506E versus 16.1% (n = 10) in the control group (P = .638). There was no mortality or graft failure among the 44 recipients enrolled in this additional 39-month follow-up study. There was 1 patient with biopsy-proven acute cellular rejection episode (2.3%) who underwent steroid pulse therapy with renal function recovery. At the time of study completion 40/44 recipients (90.9%) maintained FK506E treatment.

CONCLUSION

This 39-month study following the initial 6-month FK506E study period showed an FK506E-based immunosuppressive regimen in living donor kidney transplantation recipients to be safe and effective.

Adult dual kidney transplantations obtained from marginal donors: two case reports

Organ shortage has led us to use grafts from expanded criteria donors (ECD). Dual kidney transplantation (DKT) using organs from an ECD, which are not acceptable for single kidney transplantation (KT), may overcome the insufficient functioning nephron mass. We performed DKTs in two recipients, the first DKT to be reported from Korea. In case 1, the donor was a 36-year-old man with hypertension. The cause of his brain death was intracranial hemorrhage. He had no known underlying renal disease; his serum creatinine level was 4.2 mg/dL. Despite the relatively young age of the donor, a biopsy revealed mild interstitial fibrosis and tubular atrophy with moderate arteriolar narrowing. The recipient's postoperative course was uneventful over the 69-month follow-up; her last serum creatinine was 1.3 mg/dL. In case 2, the 80-year-old male donor with a history of hypertension had a normal creatinine. The donor biopsy revealed mild glomerular sclerosis, tubular atrophy, and interstitial fibrosis with moderate arteriolar narrowing. The recipient had undergone a previous KT 14 years previously on the right side of the abdomen, but had resumed dialysis 2 years previously due to chronic allograft nephropathy. There was no delayed graft function. At month 4 posttransplantation, lymphoceles were treated by fenestration. At 6-month follow-up, her creatinine was 1.0 mg/dL. In our experience with these two cases, DKT with ECD kidney grafts seemed to be a successful strategy to avoid poor graft outcomes and overcome the donor organ shortage. Further studies including histological criteria for DKT, should be performed to determine the safest means to utilize ECD grafts.

Treatment outcome of postoperative radiotherapy for retroperitoneal sarcoma

Purpose

To evaluate the treatment outcome and prognostic factor after postoperative radiotherapy in retroperitoneal sarcoma.

Materials and Methods

Forty patients were treated with surgical resection and postoperative radiotherapy for retroperitoneal sarcoma from August 1990 to August 2008. Treatment volume was judged by the location of initial tumor and surgical field, and 45-50 Gy of radiation was basically delivered and additional dose was considered to the high-risk area.

Results

The median follow-up period was 41.4 months (range, 3.9 to 140.6 months). The 5-year overall survival (OS) was 51.8% and disease free survival was 31.5%. The 5-year locoregional recurrence free survival was 61.9% and distant metastasis free survival was 50.6%. In univariate analysis, histologic type (p = 0.006) was the strongest prognostic factor for the OS and histologic grade (p = 0.044) or resection margin (p = 0.032) had also effect on the OS. Histologic type (p = 0.004) was unique significant prognostic factor for the actuarial local control.

Conclusion

Retroperitoneal sarcoma still remains as a poor prognostic disease despite the combined modality treatment including surgery and postoperative radiotherapy. Selective dose-escalation of radiotherapy or combination of effective chemotherapeutic agent must be considered to improve the treatment result especially for the histopathologic type showing poor prognosis.

A prospective longitudinal study evaluating the usefulness of a T-cell-based assay for latent tuberculosis infection in kidney transplant recipients

We evaluated whether ELISPOT assay can predict tuberculosis (TB) development in kidney-transplantation (KT) recipients with a negative tuberculin skin test (TST). All adult patients admitted to a KT institute between June 2008 and December 2009 were enrolled; TB development after KT was observed between June 2008 and December 2010. Isoniazid (INH) was given to those patients with positive TST or clinical risk factors for latent TB infection (LTBI). ELISPOT assay was performed on all patients, and TB development after KT was observed by a researcher blinded to the results of ELISPOT. A total of 312 KT recipients including 242 (78%) living-donor KT were enrolled. Of the 312 patients, 40 (13%) had positive TST or clinical risk factors for LTBI and received INH; none developed TB after KT. Of the remaining 272 patients, 4 (6%) of 71 with positive ELISPOT assay developed TB after KT, whereas none of the 201 patients with negative (n = 171) or indeterminate ELISPOTs (n = 30) developed TB after KT (rate difference between positive and negative/indeterminate ELISPOT, 3.3 per 100 person-years [95% CI 1.4-5.1, p<0.001]). Positive ELISPOT results predict subsequent development of TB in KT recipients in whom LTBI cannot be detected by TST or who lack clinical risk factors for LTBI.

Aurintricarboxylic acid promotes the conversion of naive CD4+CD25- T cells into Foxp3-expressing regulatory T cells

Naive peripheral CD4(+)CD25(-) T cells can be converted into Foxp3-expressing regulatory T cells under appropriate stimulation conditions. Considering that continuous exposure to antigens is one of the prerequisites for the differentiation and maintenance of Treg cells, we investigated whether preventing activation-induced cell death while providing continuous TCR stimulation could promote the expression of Foxp3 in murine naive CD4(+) T cells. Among the several anti-apoptotic agents tested, aurintricarboxylic acid (ATA) was found to induce the in vitro conversion of naive CD4(+) T cells into Foxp3(+) Treg cells with suppressive activity. Neutralizing studies with an antibody against transforming growth factor (TGF)-β revealed that ATA requires the presence of TGF-β to induce Foxp3 expression in naive CD4(+)CD25(-) T cells. Although ATA itself did not activate the Smad signaling pathway, it down-regulated the extracellular signal-regulated kinase and mammalian target of rapamycin signaling cascade in activated T cells. Lastly, combined exposure to ATA and TGF-β had a synergistic effect on the rate of induction and maintenance of Foxp3 expression. These results indicate that ATA could be exploited to efficiently prepare inducible regulatory T cells in vitro and may aid in more precisely identifying the specific signaling pathways that drive Foxp3 expression in T cells.

Bone marrow-derived mesenchymal stromal cells support rat pancreatic islet survival and insulin secretory function in vitro

BACKGROUND AIMS

Recent evidence has suggested that transplanted bone marrow (BM)-derived mesenchymal stromal cells (MSC) are able to engraft and repair non-hematopoietic tissues successfully, including central nervous system, renal, pulmonary and skin tissue, and may possibly contribute to tissue regeneration. We examined the cytoprotective effect of BM MSC on co-cultured, isolated pancreatic islets.

METHODS

Pancreatic islets and MSC isolated from Lewis rats were divided into four experimental groups: (a) islets cultured alone (islet control); (b) islets cultured in direct contact with MSC (IM-C); (c) islets co-cultured with MSC in a Transwell system, which allows indirect cell contact through diffusible media components (IM-I); and (d) MSC cultured alone (MSC control). The survival and function of islets were measured morphologically and by analyzing insulin secretion in response to glucose challenge. Cytokine profiles were determined using a cytokine array and enzyme-linked immunosorbent assays.

RESULTS

Islets contact-cultured with MSC (IM-C) showed sustained survival and retention of glucose-induced insulin secretory function. In addition, the levels of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) were decreased, and tissue inhibitor of metalloproteinases-1 (TIMP-1) and vascular endothelial growth factor (VEGF) levels were increased at 4 weeks in both the IM-C and IM-I groups.

CONCLUSIONS

These results indicate that contact co-culture is a major factor that contributes to islet survival, maintenance of cell morphology and insulin function. There might also be a synergic effect resulting from the regulation of inflammatory cytokine production. We propose that BM MSC are suitable for generating a microenvironment favorable for the repair and longevity of pancreatic islets.

Hyperuricemia in kidney transplant recipients with intact graft function

OBJECTIVES

The aim of this study was to investigate the prevalence of hyperuricemia and factors predicting its occurrence, and to establish the relationship over time between serial changes in estimated glomerular filtration rate (eGFR) and uric acid (UR) concentration in kidney transplant (KT) recipients with eGFR >60 mL/min/1.73 m(2).

METHODS

Adult patients who underwent KT at the Asan Medical Center between 1990 and 2008 and maintained eGFR >60 mL/min/1.73 m(2) were retrospectively assessed. Clinical and laboratory data were obtained from inpatient and outpatient charts and from the hospital electronic database.

RESULTS

Of 356 patients, 301 (84.55%) had normal UR levels and 55 (15.45%) had hyperuricemia. After multivariate adjustment, transplant duration, male gender, eGFR, diabetes mellitus (DM), and calcium level were associated with higher mean UR levels. Mean UR level increased significantly and mean eGFR decreased significantly during the first year after transplantation, but there were no significant differences over the next 4 years. Serial UR and eGFR levels changed almost simultaneously.

CONCLUSIONS

Transplantation duration, male gender, eGFR level, DM, and serum calcium level were risk factors for hyperuricemia in kidney recipients with intact graft function. Increased uric acid after KT did not significantly affect graft function.

Interleukin (IL)-10 induced by CD11b(+) cells and IL-10-activated regulatory T cells play a role in immune modulation of mesenchymal stem cells in rat islet allografts

Mesenchymal stem cells (MSCs) are suggested to be immune modulators because of their therapeutic potential in transplantation. In the present study, we evaluated the therapeutic potential of autologous MSCs for preventing graft rejection after allogeneic rat islet transplantation. We assessed the ability of MSCs to elicit an antiproliferative response in alloreactive lymphocytes and tested the immunosuppressive effect of MSCs in allogeneic islet transplantation. In islet allotransplantation, injection of autologous MSCs or a subtherapeutic dose of cyclosporine A (CsA; 5 mg/kg) alone did not prolong allograft survival. However, graft survival was attained for >100 d in 33% of autologous MSC-plus-CsA-treated recipients, indicating that graft acceptance was achieved in a subgroup of allograft recipients. Splenocytes from autologous MSC-plus-CsA-treated rats exhibited a reduced mixed lymphocyte reaction (MLR)-proliferative response to donor stimulators and increased interleukin (IL)-10 release. Interestingly, after excluding host CD11b(+) cells, splenic T cells from autologous MSC-plus-CsA-treated rats did not produce IL-10 or did not inhibit proliferative responses under the same conditions. The use of autologous MSC-plus-CsA downregulated immune responses, inducing donor-specific T-cell hyporesponsiveness by reducing the production of proinflammatory cytokines and inducing antiinflammatory cytokine production, especially that of IL-10, during the early posttransplantation period. T-regulatory cells made a contribution at a later phase. In conclusion, the combined use of autologous MSCs and low-dose CsA exerted a synergistic immunosuppressive effect in an islet allograft model, suggesting a role for autologous MSCs as an immune modulator.

The synergistic effect of Tautomycetin on Cyclosporine A-mediated immunosuppression in a rodent islet allograft model

Most immunosuppressive drugs that support successful allograft survival act by inhibiting or depleting T lymphocytes. Tautomycetin (TMC) is a specific inhibitor of protein phosphatase 1, which has a role in cell-cycle control and T-cell activation and promotes T-cell-specific apoptosis. In this study, we investigated the effect on rat islet transplantation of TMC alone and in combination with cyclosporine A (CsA). TMC treatment inhibited splenocyte proliferation in mixed lymphocyte reactions (MLR) without affecting cell viability. When used alone in islet allograft recipients, TMC did not significantly increase the survival of grafted islets. However, cotreatment of TMC and subtherapeutic doses of CsA significantly prolonged islet graft survival from 5.1 d to more than 100 d (P<0.05). At 100 d, there was no evidence of specific organ toxicity, and histological analyses of grafted liver tissue revealed the presence of viable islets. CD4+ and CD8+ T-cell infiltration and interleukin (IL)-2 mRNA levels were decreased in TMC/CsA-cotreated rats, whereas IL-10 levels were increased. In addition, the number of FoxP3-expressing cells and FoxP3 mRNA levels were also increased. We suggest that CsA and TMC act synergistically to reduce the function of T-effector cells and enhance regulatory cell function in this islet allotransplantation model.

Effect of in vitroexpanded CD4(+)CD25(+)Foxp3(+) regulatory T cell therapy combined with lymphodepletion in murine skin allotransplantation

A promising approach for preventing allograft rejection involves shifting the balance between cytopathic and regulatory T cells to dominance of the latter cell type. Nonspecific lymphodepletion was conducted by administration of depleting anti-CD4 and anti-CD8 antibodies to reduce effector T cells and adoptive transfer of ex vivo-expanded host Treg cells by stimulation with donor dendritic cells to augment the Treg cell compartment. Evaluation of an MHC-mismatched skin allograft model revealed that combined therapy with these two protocols consistently induced modest prolongation of allograft survival, although all skin grafts were eventually rejected. The administration of IL-2/anti-IL-2 complexes significantly improved the efficacy of combination therapy via promoting the expansion of adoptively transferred Treg cells as well as endogenous recipient Treg cells. We conclude that Treg cell therapy combined with lymphodepletion is of practical benefit for the control of allograft rejection, but requires supplementary measures to promote immune tolerance.

Suitability of the IDMS-traceable MDRD equation method to estimate GFR in early postoperative renal transplant recipients

BACKGROUND/AIMS

Accurate measurement of glomerular filtration rate (GFR) is critical for the management of kidney transplant recipients. Comparison of creatinine and cystatin C in renal transplant recipients gave conflicting results. We aimed to compare the performance of creatinine- and cystatin C-based equations and creatinine clearance in 102 early postoperative Korean renal transplant patients.

METHODS

We measured (51)Cr-EDTA clearance using a 2-compartment model and considered this the reference GFR. Then, we estimated GFR using 13 creatinine- and 7 cystatin C-based equations. Serum creatinine value was calibrated to isotope-dilution mass spectrometry (IDMS).

RESULTS

The mean reference GFR was 76.77 +/- 17.01 ml/min/1.73 m(2). The IDMS-traceable MDRD (IDMS-MDRD) equation had the highest accuracy (94.12 within 30% of the reference; 99.02 within 50% of the reference) with a bias of 0.33 ml/min/1.73 m(2) and a precision of 12.57 ml/min/1.73 m(2). The Mayo Clinic equation also performed well (92.16% within 30% of the reference; 99.02% within 50% of the reference; bias: -0.19 ml/min/1.73 m(2)). As for cystatin C-based equations, the Filler equation had the least bias (0.03 ml/min/1.73 m(2)) but low accuracy (78.43% within 30% of the reference).

CONCLUSIONS

We conclude that the IDMS-MDRD equation provided the best estimate of GFR in our early postoperative Korean renal transplant patients.

A randomised phase II study of modified FOLFIRI.3 vs modified FOLFOX as second-line therapy in patients with gemcitabine-refractory advanced pancreatic cancer

Background:

Only a few clinical trials have been conducted in patients with advanced pancreatic cancer after failure of first-line gemcitabine-based chemotherapy. Therefore, there is no current consensus on the treatment of these patients. We conducted a randomised phase II study of the modified FOLFIRI.3 (mFOLFIRI.3; a regimen combining 5-fluorouracil (5-FU), folinic acid, and irinotecan) and modified FOLFOX (mFOLFOX; a regimen combining folinic acid, 5-FU, and oxaliplatin) regimens as second-line treatments in patients with gemcitabine-refractory pancreatic cancer.

Methods:

The primary end point was the 6-month overall survival rate. The mFOlFIRI.3 regimen consisted of irinotecan (70 mg m⁻²; days 1 and 3), leucovorin (400 mg m⁻²; day 1), and 5-FU (2000 mg m⁻²; days 1 and 2) every 2 weeks. The mFOLFOX regimen was composed of oxaliplatin (85 mg m⁻²; day 1), leucovorin (400 mg m⁻²; day 1), and 5-FU (2000 mg m⁻²; days 1 and 2) every 2 weeks.

Results:

Sixty-one patients were randomised to mFOLFIRI.3 (n=31) or mFOLFOX (n=30) regimen. The six-month survival rates were 27% (95% confidence interval (CI)=13–46%) and 30% (95% CI=15–49%), respectively. The median overall survival periods were 16.6 and 14.9 weeks, respectively. Disease control was achieved in 23% (95% CI=10–42%) and 17% patients (95% CI=6–35%), respectively. The number of patients with at least one grade 3/4 toxicity was identical (11 patients, 38%) in both groups: neutropenia (7 patients under mFOLFIRI.3 regimen vs 6 patients under mFOLFOX regimen), asthaenia (1 vs 4), vomiting (3 in both), diarrhoea (2 vs 0), and mucositis (1 vs 2).

Conclusion:

Both mFOLFIRI.3 and mFOLFOX regimens were tolerated with manageable toxicity, offering modest activities as second-line treatments for patients with advanced pancreatic cancer, previously treated with gemcitabine.

Clinical outcomes of multicenter domino kidney paired donation

Domino kidney paired donation (KPD) is a method by which an altruistic living nondirected donor (LND) is allocated to a pool of incompatible donor-recipient pairs (DRP) and a series of KPDs is initiated. To evaluate the feasibility and clinical outcomes of multicenter domino KPD, we retrospectively analyzed a cohort of DRPs who underwent domino KPD between February 2001 and July 2007 at one of 16 transplant centers. One hundred seventy-nine kidney transplants were performed, with 70 domino chains initiated by altruistic LND. There were 45 two-pair chains, 15 three-pair chains, 7 four-pair chains, 2 five-pair chains and 1 six-pair chain. A majority of donors were spouses (47.5%) or altruistic LNDs (39.1%). DRPs with a blood type O recipient or an AB donor comprised 45.9% of transplanted DRPs. HLA mismatch improved in transplanted donors compared to intended donors in pairs enrolled to improve HLA mismatch (3.4 +/- 0.7 vs. 4.8 +/- 1.0, p < 0.001). One-year and 5-year graft survival rates were 98.3% and 87.7%, respectively, with a median follow-up of 46 months. One-year and 5-year patient survival rates were 97.2% and 90.8%, respectively. In conclusion, multicenter domino KPD could multiply the benefits of donation from LNDs, with patients and graft survival rates comparable to those seen with conventional KPD.

Parainfluenza virus 3 pneumonia in a kidney transplant recipient

We report the first case of parainfluenza virus type 3 (PIV3) pneumonia in a kidney transplant recipient. A 39-year-old man developed pneumonia during hospitalization 6 years after kidney transplantation. He became hypoxic and underwent noninvasive ventilation. PIV3 was detected in the bronchoalveolar lavage fluid. He was treated successfully with aerosolized ribavirin and intravenous immunoglobulin. Although he recovered from pneumonia, his graft function deteriorated and he had to restart peritoneal dialysis.

Glutamine induces heat-shock protein-70 and glutathione expression and attenuates ischemic damage in rat islets

BACKGROUND

The transplantation of isolated islets is believed to be an attractive approach for cure of diabetes mellitus. Heat-shock protein (HSP70), which plays a vital role in cellular protection, has been detected in various tissues subjected to stress. Glutamine (GLN) is an important cellular fuel and an essential precursor for the antioxidant glutathione (GSH). It is believed to enhance cellular survival against a variety of stressful stimuli through HSP70. Thus, we performed this study to examine the hypothesis that preoperative GLN administration induces HSP70 and GSH expression before islet transplantation attenuating ischemic damage to rat islets.

METHODS

Adult male Sprague-Dawley (SD) rats were randomly divided into two groups according to the administration of GLN after islet isolation. Group A served as the controls, receiving no GLN. Group B islet cells were cultured with L-GLN (10 mmol/L) supplementation for 24 hours. The GSH levels were measured in islet cells. Both HSP70 and proteins related to apoptosis were analyzed in islet cells by Western blots. Isolated rat islets were cultured with interleukin (IL)-1beta. Nitrite production was measured using the Griess reagent.

RESULTS

The GSH levels were significantly elevated in the glutamine-treated group. HSP70 expression in islets treated with GLN was markedly stronger compared with the control group. The basal Bcl-2 expression was markedly increased by GLN treatment. The GLN-treated group showed attenuated IL-1beta-induced injury in association with NO production.

CONCLUSION

These results suggested that preoperative GLN administration induced HSP70 and GSH expressions before islet transplantation, thus attenuating IL-1beta-induced injury in association with NO production and apoptosis, which might be potential tool to mitigate the ischemic damage to islet cells and the early inflammation at the site of implantation through a self-protective mechanism.

Improved islet yields after purification following the novel endogenous trypsin inhibitor and histidine-tryptophan-ketoglutarate treatment in pigs

BACKGROUND

Adult porcine islet xenotransplantation into humans is greatly diminished by the difficulty to isolate islets because of their fragility. The goal of this study was to improve the efficacy of islet yields using endogenous trypsin inhibitor and histidine-tryptophan-ketoglutarate (HTK) perfusate.

METHOD

We compared two porcine islet isolation protocols: Eurocollins solution for in situ pancreas perfusion without use of an endogenous trypsin inhibitor versus HTK solution including endogenous trypsin inhibitor for pancreas perfusion.

RESULTS

Endogenous trypsin inhibitor and HTK strategies significantly improved total islet yield, recovery, and islet index after purification (P < .05), whereas unpurified islet yield did not increase. An average of 228,000 +/- 95,000 islet equivalents (IEQ) (n = 20) purified islets were obtained in the first group compared with 115,000 +/- 56,000 IEQ (n = 18) in the second group. The average islet index was significantly increased in the first group compared with the second group before and after purification: before: 0.28 versus 0.49 versus after: 0.25 versus 0.4 (P < .05). At this time, islet purity, viability, and stimulation index did not show a significant difference between groups.

CONCLUSION

Our study showed that endogenous trypsin inhibitor and HTK strategies significantly improved purified islet isolation efficacy because of reduction of islet fragility.

Experimental microencapsulation of porcine and rat pancreatic islet cells with air-driven droplet generator and alginate

Transplantation of microencapsulated islets is proposed as an ideal therapy for the treatment of type 1 diabetes mellitus without immunosuppression. This strategy is based on the principle that foreign cells are protected from the host immune system by an artificial membrane. The aim of this study was to establish an ideal condition of microencapsulation using an air-driven droplet generator and alginate in vitro. The optimal conditions for islet encapsulation were an alginate inflow rate of 10 mL/h, CO2 flow rate of 2.0 L/min in a concentration of 2% alginate. For 2.5% alginate, the alginate inflow rate of 20 mL/h, CO2 flow rate 3.0 L/min was ideal; alginate inflow rate of 40 mL/h, CO2 flow rate of 4.0 L/min showed good microcapsules at 3% alginate. Viability of encapsulated islets was greater than 90%. In terms of insulin secretion, encapsulated islets secreted insulin in response to glucose in static culture medium. However, there was no normal response to low or high glucose challenge with a stimulation index less than 2.0. Microencapsulation of pig islets was successfully performed with air-driven droplet generator and alginate in vitro. Further studies about biocompatibility and glucose control in vivo may provide a useful tool for treatment of patients with diabetes mellitus.

Viral IL-10 gene transfer prolongs rat islet allograft survival

Islet transplantation is a potential cure for diabetes. However, allotransplant rejection severely limits its clinical application. In this study, we sought to transfect rat islets with an adenoviral vector containing the viral IL-10 (vIL-10) gene and examine its efficacy in preventing graft rejection. The immunosuppressive effect of vIL-10 is reported but its efficacy is somehow debatable in transplantation model. vIL-10 transfected islets were transplanted into streptozotocin-induced diabetic rats. Blood glucose, serum vIL-10 concentration, graft histology, and graft cytokine expression were used to monitor graft function up to day 21 after transplantation. Transfected islets released a large amount of vIL-10 protein without affecting their viability and functional integrity. When we transplanted the transfected islets into allogeneic hosts, the survival of grafted islets was not significantly increased. However, the combined use of vIL-10 and subtherapeutic doses of CsA (cyclosporine) significantly prolonged graft survival beyond that achieved with either agent alone (p < 0.001). vIL-10 and CsA-treated rats contain high level of vIL-10 in serum, which is evidenced by the inhibition of allogeneic mixed lymphocyte reaction (MLR). Histological analysis additionally revealed the presence of viable islets up to 21 days. IL-10 mRNA expression in grafted liver was higher and IFN-gamma mRNA was lower in vIL-10 and CsA-treated animals, compared with other groups. The synergistic effect of this combination therapy is potentially correlated with the induction of inhibitory cytokine secretion and downregulation of proinflammatory cytokine secretion from host cells.

Cell Surface Modification by Activated Polyethylene Glycol Prevents Allosensitization after Islet Transplantation

The necessity to transplant islet tissue without the need for immunosuppressant therapy has led to the development of materials for immune modulation. Pegylation makes islets antigenically silent, protecting them from the adsorption of foreign protein and thus avoiding immune injury. The aim of this study is to determine whether pegylation of islets prolongs islet survival and function both during tissue culture and posttransplantation. We used cyanuric chloride-activated methoxy-polyethylene glycol for cell surface modification. To detect the pegylation effect on splenocytes, we measured antibody binding inhibition and abrogation of lymphocyte proliferation. To detect the pegylation effect on islet grafts, we performed rodent islet transplantation. Islet viability and function were maintained after pegylation. Pegylated islets showed a 90% decrease in antibody binding and decreased lymphocyte proliferation in a mixed lymphocyte culture. However, when pegylated islets were transplanted, no prolongation of graft survival was observed. When a subtherapeutic dose of immunosuppressant was given at the time of transplantation of pegylated islets, islet graft survival was significantly prolonged. In addition, when rats were sensitized with donor splenocytes, graft survival was prolonged by pegylation. We observed that pegylation of islets, combined with a subtherapeutic dose of immunosuppressant, protects the graft from rejection. Prolonged graft survival in sensitized recipients showed that pegylation of islets shifted the pattern of rejection from an acute humoral response to a less aggressive cellular alloresponse.

In vitro differentiation of human adipose tissue-derived stem cells into cells with pancreatic phenotype by regenerating pancreas extract

Pancreas extract from regenerating pancreas after partial pancreatectomy is known to contain factors that induce islet neogenesis in animals with streptozotocin (STZ)-induced diabetes [A.A. Hardikar, R.R. Bhonde, Modulating experimental diabetes by treatment with cytosolic extract from the regenerating pancreas, Diabetes Res. Clin. Pract. 46 (1999) 203-211]. In this study, we evaluate the effects of regenerating pancreas extract (RPE) from 90% partially pancreatectomized rats on induction of pancreatic differentiation of human adipose tissue-derived stem cells (hASCs). We found that undifferentiated hASCs expressed OCT-3/4, Nanog, and REX-1, markers of embryonic stem cells (ESCs). Genes involved in early pancreas development showed increased expression in RPE-treated culture. Sox17 and IPF-1 were expressed only in RPE-treated culture. Immunocytochemical analysis showed C-peptide-positive cells in RPE-treated culture but not in undifferentiated hASCs. In conclusion, hASCs have the characteristics of ESCs and the potential to differentiate into pancreas cell lineages phenotypically in response to RPE.

A controllable double-well magneto-optical trap for Rb and Cs atoms

We experimentally demonstrate a novel scheme to simultaneously confine two atomic species of (87)Rb and (133)Cs with adjustable spatial separation by a controllable double-well magneto-optic trap. Using a single-loop wire and a magnetic bias field, the two clouds, each containing more than 1 x 10(6) atoms, are spatially separated above and below the wire center of the double-well MOT. The cloud interdistance can be controlled by independently varying the wire current and external bias field. This allows to load the double-well magnetic trap, and to study the dynamics of cold collisions between two-species atoms.

Effect of kimchi powder level and drying methods on quality characteristics of breakfast sausage

This study was conducted to determine the effect of the addition of kimchi powder on the quality characteristics of meat batter and breakfast sausage. Breakfast sausages were supplemented with freeze dried kimchi powder (FKP) or hot air dried kimchi powder (HKP) at levels of 1% (FKP-1 and HKP-1) or 2% (FKP-2 and HKP-2). The emulsion stability, cooking yield, and apparent viscosity in meat batters improved with increments of kimchi powder (p<0.05). Increased levels of kimchi powder in breakfast sausage decreased the L(∗) value, pH, and springiness, and increased the a(∗) value, b(∗) value, hardness, chewiness, and gumminess (p<0.05). Sensory evaluations indicated that a higher overall acceptability was attained when the kimchi powder was added to breakfast sausage at a level of 2%.

Effect of immunosuppressants on the expansion and function of naturally occurring regulatory T cells

The induction of immune tolerance is one of the final therapeutic goals in clinical transplantation. Regulatory T lymphocytes are important for the induction and maintenance of immune tolerance to grafts. If immunosuppressive drugs used clinically to prevent immune rejection also inhibit regulatory T lymphocytes, tolerance would not be achieved. We therefore tested the effect of several immunosuppressants with different mechanisms of action on the proliferation and suppressive activity of CD4(+)CD25(+) regulatory T cells. Highly purified CD4(+)CD25h(+) T cells from C57BL/6 (H-2(b)) mice were stimulated with allogeneic T-depleted splenocytes (BALB/c; H-2(d)) in the presence of various immunosuppressants. After one week in culture, viable T cells were recovered, their regulatory capacity was assessed by their ability to inhibit responder T cell proliferation in MLR, and their cytokine production profile was measured by ELISA. The immunosuppressants rapamycin, cyclosporine A, and methylprednisolone significantly inhibited the expansion of regulatory T cells upon stimulation with alloantigen, whereas mycophenolic acid and the costimulatory blockers, anti-CD40L and CTLA4Ig, did not. None of these immunosuppressants, however, reduced the suppressive capacity of regulatory T cells. Pretreatment with immunosuppressants did not induce significant changes in the cytokine production profile of regulatory T cells. Our results suggest that costimulatory blockers and mycophenolate mofetil can be utilized therapeutically in the induction of immune tolerance. In contrast, the use of rapamycin, cyclosporine A, and methylprednisolone should be reconsidered, due to their deleterious effects on the expansion of naturally occurring regulatory T cells.

Comparative study on biologic and immunologic characteristics of the pancreas islet cell between 24 degrees C and 37 degrees C culture in the rat

The aim of this study was to investigate the effect of culture at 24 degrees C on cell viability, cellular function, immunogenicity, and cytokine profiles of rat pancreatic islets. Pancreatic islets were isolated from Lewis rats and cultured at either 24 degrees C or 37 degrees C for 14 days. Islet recovery was counted as islet equivalents; islet viability was examined with fluorescent vital staining. Islet function was measured with a glucose stimulation test. Annexin V, and MHC class I and II expression were measured using flow cytometric assay for apoptosis and immunogenicity, respectively. Lymphocyte cell proliferation was examined with WST-1 proliferation assay. Cytokine profiles were analyzed with quantitative real time RT-PCR. All these parameters were measured on 1, 3, 5, 7 and 14 culture days after islet isolation. Islet recovery was higher in islets cultured at 24 degrees C than 37 degrees C without a change in viability. Insulin secretion after glucose stimulation was more effective in 24 degrees C culture conditions. Decreased apoptotic cell death was demonstrated in 24 degrees C cultured islets. Both MHC class I and II expression on islets and lymphocyte proliferation upon coculture with islets were less prominent in 24 degrees C cultured islets. TNF-alpha expression was lower in islets cultured at 24 degrees C than in islets cultured at 37 degrees C. Both IL-1beta and IL-10 cytokine expressions were similar under both culture conditions. This study demonstrated that cell recovery and function are increased in islets cultured at 24 degrees C than those at 37 degrees C with decreased antigenicity and proinflammatory cytokine expression.

Analysis on Donor and Isolation-Related Factors of Successful Isolation of Human Islet of Langerhans From Human Cadaveric Donors

We analyzed the preexisting donor factors and isolation variables that affected isolation of human islets of Langerhans. Sixty-nine pancreata from cadaveric donors were analyzed for donor factors of age, gender, body mass index, cause of death as well as graft factors of cold ischemia time, pancreas status, distensibility during intraductal collagenase distension and time of collagenase expansion and digestion. Islet isolations that recovered >100,000 IEQ (n = 53) were compared to those generating less than 100,000 IEQ (n = 16) to analyze the factors affecting islet yield during donor harvest and isolation procedures. The mean islet recovery was 216.0 x 10(3) (IEQ) or 2840 (IEQ) per gram of pancreas. Mean purity was 54%. The success rate of islet isolation was 76%. Mean age was 31 years, and mean cold ischemia time was 6.9 hours. In univariate analysis, the status of the pancreas was the only significant factor for successful isolation, and gender, time of collagenase expansion and digestion were marginal factors. In stepwise multivariate logistic regression analysis of donor and isolation-related factors, donor gender, pancreas status and digestion time were significant factors. During the same period we performed three cases of clinical islet allotransplantation and one autotransplantation. This study confirmed that the same donor factors and variables in the isolation process can affect the ability to obtain successful human islet isolation. Enough experience and pertinent review of donor and isolation factors can make islet isolation consistent, supporting clinical islet transplantation without unnecessary cost.

An inexact fuzzy two-stage stochastic model for quantifying the efficiency of nonpoint source effluent trading under uncertainty

Reduction of nonpoint source (NPS) pollution from agricultural lands is a major concern in most countries. One method to reduce NPS pollution is through land retirement programs. This method, however, may result in enormous economic costs especially when large sums of croplands need to be retired. To reduce the cost, effluent trading can be employed to couple with land retirement programs. However, the trading efforts can also become inefficient due to various uncertainties existing in stochastic, interval, and fuzzy formats in agricultural systems. Thus, it is desired to develop improved methods to effectively quantify the efficiency of potential trading efforts by considering those uncertainties. In this respect, this paper presents an inexact fuzzy two-stage stochastic programming model to tackle such problems. The proposed model can facilitate decision-making to implement trading efforts for agricultural NPS pollution reduction through land retirement programs. The applicability of the model is demonstrated through a hypothetical effluent trading program within a subcatchment of the Lake Tai Basin in China. The study results indicate that the efficiency of the trading program is significantly influenced by precipitation amount, agricultural activities, and level of discharge limits of pollutants. The results also show that the trading program will be more effective for low precipitation years and with stricter discharge limits.