Surgical Outcomes of Ipsilateral Inguinal Hernia After Kidney Transplantation

OBJECTIVES

We aimed to clarify the clinical features and outcomes of ipsilateral inguinal hernias after kidney transplantation.

PATIENTS AND METHODS

Eleven patients diagnosed with inguinal hernia on the ipsilateral side after kidney transplantation between 2011 and 2022 were analyzed. Clinical data were retrospectively reviewed from the medical records.

RESULT

Eleven patients were included in the analysis (median age, 68 [range, 28-75] years, male, n = 11). The time from kidney transplantation to hernia surgery was 107 (6-393) months. Eight patients had direct-type inguinal hernias. Three had indirect-type inguinal hernias. Hernia contents included the small intestine (n = 5), transplanted ureter and bladder (n = 2), only bladder (n = 1), transplanted kidney, ureter, and small intestine (n = 1), transplanted kidney and small intestine (n = 1), and transplanted ureter (n = 1). Six patients (55%) were diagnosed with urinary tract obstruction due to inguinal hernia. All hernias were repaired using mesh. The plug method was used in 9 cases. The Lichtenstein method was used in 2 cases. The median operative time was 110 (73-155) minutes, and the median blood loss was 3 (1-85) mL. The median postoperative hospital stay was 4 (2-7) days. In the 6 patients with urinary obstruction, the serum creatinine levels improved (P = .028), and the transplanted urinary tract obstruction disappeared after surgery. There was no recurrence of inguinal hernia. One patient experienced chronic pain in the groin area (Clavien-Dindo grade II) during follow-up.

CONCLUSION

Surgical intervention for inguinal hernia after kidney transplantation is safe and effective for preventing worsening of the kidney graft function.

Arteriolar hyalinization at 0-hour biopsy predicts long-term graft function in deceased kidney transplantation

OBJECTIVES

Regarding the relationship between donor kidney quality and renal graft function after deceased kidney transplantation (KTx) following donation after cardiac death (DCD), the evaluation timing varies depending on the study. Evaluation of histology and changes in long-term renal graft function is limited.

METHODS

A retrospective single-center study included 71 recipients who underwent 0-hour biopsy for KTx from DCD. The recipients were divided into two groups to evaluate factors related to renal graft function (study1). The two groups were categorized as stable graft function and poor graft function with the change of estimated glomerular filtration rate (eGFR) after KTx. The recipients were then divided into four groups to assess whether the factors identified in study1 were related to the change in long-term renal graft function (study2). They were categorized as follows: Improved, Stable, Deteriorated, and Primary non-function with the change of eGFR after KTx.

RESULTS

In study1, donor age ≥ 50 years (29.5% vs. 65.2%; p = 0.09), banff arteriolar hyalinosis (ah) score (0.66 ± 0.78 vs. 1.2 ± 1.0; p = 0.018), and presence of glomerulosclerosis (43.2% vs. 76.2%; p = 0.017) were significant risk factors for poor long-term graft function. When the recipients were divided into four groups, the severity of ah correlated well with changes in long-term renal function.

CONCLUSIONS

We can predict the shift in long-term renal graft function after KTx from DCD according to the severity of ah by 0-hour biopsy.

Immunological risk and complement genetic evaluations in early onset de novo thrombotic microangiopathy after living donor kidney transplantation: A Japanese multicenter registry

BACKGROUND

Thrombotic microangiopathy (TMA) after kidney transplantation (KTx), particularly early onset de novo (dn) TMA, requires immediate interventions to prevent irreversible organ damage. This multicenter study was performed to investigate the allogeneic clinical factors and complement genetic background of dnTMA after KTx.

METHODS

Perioperative dnTMA after KTx within 1 week after KTx were diagnosed based on pathological or/and hematological criteria at each center, and their immunological backgrounds were researched. Twelve aHUS-related gene variants were examined in dnTMA cases.

RESULTS

Seventeen recipients (15 donors) were enrolled, and all dnTMA cases were onset within 72-h of KTx, and 16 of 17 cases were ABO incompatible. The implementation rate of pre-transplant plasmaphereses therapies were low, including cases with high titers of anti-A/anti-B antibodies. Examination of aHUS-related gene variants revealed some deletions and variants with minor allele frequency (MAF) in Japan or East Asian genome databases in genes encoding alternative pathways and complement regulatory factors. These variants was positive in 8 cases, 6 of which were positive in both recipient and donor, but only in one graft loss case.

CONCLUSIONS

Although some immunological risks were found for dnTMA after KTx, only a few cases developed into TMA. The characteristic variations revealed in the present study may be novel candidates related to dnTMA in Japanese or Asian patients, but not pathogenic variants of aHUS. Future studies on genetic and antigenic factors are needed to identify factors contributing to dnTMA after KTx.

MicroRNAs as Potential Regulators of GSK-3β in Renal Cell Carcinoma

The prognosis of patients with advanced renal cell carcinoma (RCC) has improved with newer therapies, including molecular-targeted therapies and immuno-oncology agents. Despite these therapeutic advances, many patients with metastatic disease remain uncured. Inhibition of glycogen synthase kinase-3β (GSK-3β) is a promising new therapeutic strategy for RCC; however, the precise regulatory mechanism has not yet been fully elucidated. MicroRNAs (miRNAs) act as post-translational regulators of target genes, and we investigated the potential regulation of miRNAs on GSK-3β in RCC. We selected nine candidate miRNAs from three databases that could potentially regulate GSK-3β. Among these, hsa-miR-4465 (miR-4465) was downregulated in RCC cell lines and renal cancer tissues. Furthermore, luciferase assays revealed that miR-4465 directly interacted with the 3' untranslated region of GSK-3β, and Western blot analysis showed that overexpression of miR-4465 significantly decreased GSK-3β protein expression. Functional assays showed that miR-4465 overexpression significantly suppressed cell invasion of A498 and Caki-1 cells; however, cell proliferation and migration were suppressed only in Caki-1 and A498 cells, respectively, with no effect on cell cycle and apoptosis. In conclusion, miR-4465 regulates GSK-3β expression but does not consistently affect RCC cell function as a single molecule. Further comprehensive investigation of regulatory networks is required in this field.

Long-term CMV monitoring and chronic rejection in renal transplant recipients

Introduction

Cytomegalovirus (CMV) is well established to be an independent risk factor for graft loss after kidney transplantation (KTx). Monitoring for CMV in the chronic phase is not defined in the current guideline. The effects of CMV infection, including asymptomatic CMV viremia, in the chronic phase are unclear.

Methods

We performed a single-center retrospective study to investigate incidence of CMV infection in the chronic phase, defined as more than 1 year after KTx. We included 205 patients who received KTx between April 2004 and December 2017. The CMV pp65 antigenemia assays to detect CMV viremia were continuously performed every 1-3 months.

Results

The median duration of the follow-up was 80.6 (13.1-172.1) months. Asymptomatic CMV infection and CMV disease were observed in 30.7% and 2.9% in the chronic phase, respectively. We found that 10-20% of patients had CMV infections in each year after KTx which did not change over 10 years. The history of CMV infection in the early phase (within 1 year after KTx) and chronic rejection were significantly associated with CMV viremia in the chronic phase. CMV viremia in the chronic phase was significantly associated with graft loss.

Discussion

This is the first study to examine the incidence of CMV viremia for 10 years post KTx. Preventing latent CMV infection may decrease chronic rejection and graft loss after KTx.

Acquisition of Antibody Against Cytomegalovirus After Kidney Transplantation in Seronegative Recipients

BACKGROUND

Cytomegalovirus (CMV) infection is one of the most important infectious diseases affecting recipients of kidney transplantation (KTx). However, the timing of seroconversion for CMV infection in seronegative recipients remains unclear. We evaluated CMV infections in CMV-seronegative recipients and the time to acquire antibodies against CMV.

METHODS

We conducted a retrospective study of 228 recipients who underwent KTx between March 1988 and February 2018 at the Niigata University Hospital. The anti-CMV IgG antibody profile before and after transplantation was analyzed. Oral acyclovir or valganciclovir was used as prophylactic therapy for at least 6 months after transplantation. Cytomegalovirus infection was defined as CMV viremia detected using the CMV pp65 antigenemia assay.

RESULTS

In this study, 50 cases (21.9%) were CMV-seronegative recipients. Over a median follow-up period of 126.7 months, 68% (34/50) of CMV-seronegative recipients experienced CMV viremia or overt disease symptoms as the first episode of CMV infection. The median duration from transplant to CMV infection was 69.0 days (range, 22-7426). All the recipients who experienced CMV infections acquired seroconversion. The median duration from KTx to seroconversion was 7.2 months (range, 2.8-252.3). Almost all CMV-seronegative recipients could acquire anti-CMV IgG antibodies within 2.5 years. In seronegative recipients whose donors were seronegative, no CMV viremia was found, and none developed anti-CMV IgG antibodies.

CONCLUSIONS

In the clinical practice of CMV-seronegative recipients, we should consider that physicians must closely monitor the occurrence of CMV infection up until 2.5 years after KTx.

[PREGNANCIES IN KIDNEY TRANSPLANT RECIPIENTS, AN ANALYSIS OF 9 CASES]

(Objective) Pregnancy in kidney transplant recipient continues to remain challenging due to a high rate of cesarean section along with preterm delivery, and concern for worsening renal function. This study examined the prognosis and perinatal management of post-transplant pregnancies. (Patients and methods) A total of nine post-transplant recipients at Niigata University Medical and Dental Hospital between 2007 and 2021 were retrospectively examined. (Results) All pregnancies were planned. Calcineurin inhibitors and steroids were continued, and antimetabolites were changed to azathioprine. The mean age at delivery was 33±3.8 years, and the mean time from renal transplantation to delivery was 6.5±3.5 years. Five patients (55.5%) had cesarean sections, while four (44.5%) patients had normal vaginal deliveries. The mean gestational age was 35±3.0 weeks, and the mean birth weight was 2,336±565.4 g. No congenital malformation was observed. The most common reason for early delivery was worsening renal function, seen in six (66.7%) patients. The mean serum creatinine level before pregnancy was 1.11±0.23 mg/dL and then worsened to 1.59±0.37 mg/dL during pregnancy. However, it recovered to 1.14±0.40 mg/dL after delivery. One patient had antibody-mediated rejection with donor specific antibody (DSA) prior to pregnancy, and her renal graft function worsened slightly after delivery. Another patient had a de novo DSA after delivery, which was not detected before pregnancy. (Conclusions) In our hospital, pregnancy in kidney transplant recipients were safe and renal graft function after delivery was relatively stable. Patients may require adjustment of calcineurin inhibitors during pregnancy, and the appearance of DSA after delivery should be noted.

Hyporesponsiveness against donor's ABO antigens of renal grafts after ABO-incompatible kidney transplantation

BACKGROUND

ABO antigens expressed on the red blood cells (RBCs) are not identical to those expressed on the renal endothelial cells. The isohemagglutinin assay employing the RBCs is the gold standard for evaluating anti-ABO antibody (Ab) levels. However, it remains unclear whether the anti-ABO Abs detected by the isohemagglutinin assay after ABO-incompatible (ABOi) kidney transplantations (KTx) that are not associated with antibody-mediated rejection can bind to renal graft endothelial cells.

METHODS

Ninety plasma samples were collected from patients with stable graft function after ABO-compatible (ABOc) or ABOi KTx. Anti-ABO Ab titers were examined by both the isohemagglutinin assay and the CD31-ABO microarray, which was developed as a mimic of the ABO antigens expressed on the renal endothelial cells.

RESULTS

The antibody titers detected by the isohemagglutinin assay and the CD31-ABO microarray after the ABOc KTx relatively correlated with each other. However, the CD31-ABO microarray results showed low antibody levels against donor blood group antigens after ABOi KTx and did not correlate with the isohemagglutinin assay. In contrast, the antibody levels against non-donor blood group antigens after ABOi KTx were comparable to those after the ABOc KTx. Fourteen patients received graft biopsies, and no antibody-mediated rejection was observed in ABOi KTx recipients, except for two patients who had anti-donor-HLA Abs.

CONCLUSION

The present study suggested that the anti-ABO Abs detected by the isohemagglutinin assay after ABOi KTx with stable graft function were hyporeactive to the ABO antigen of graft renal endothelial cells.

Pretransplant BMI Should Be <25 in Japanese Kidney Transplant Recipients: A Single-Center Experience

BACKGROUND

The aim of this study was to determine the appropriate body mass index (BMI) in Japanese kidney transplant (KTx) recipients. We analyzed the effects of pre- and post-transplant (Tx) obesity on graft and patient survival, perioperative complications, post-transplant diabetes mellitus (PTDM), and cardiovascular disease (CVD) in Japanese KTx recipients.

METHODS

This retrospective study included 269 recipients who underwent KTx from 2008 through 2020 at Niigata University Hospital. Obesity was defined as a body mass index (BMI) ≥25 kg/m². We examined the association between pre- and post-Tx obesity and graft survival, patient survival, the incidence of PTDM and CVD, and perioperative surgical complications.

RESULTS

The graft survival rate was lower in the pre-Tx BMI ≥25 kg/m² group, although there was no significant difference in patient survival. There was no difference in graft and patient survival between the post-Tx BMI ≥25 kg/m² group and the <25 kg/m² group. A pre-Tx BMI ≥25 kg/m² was an independent risk factor for biopsy-proven allograft rejection. New-onset DM after transplantation was significantly more common in the BMI ≥25 kg/m² group than in the BMI <25 kg/m² group (36% vs 13%; P = .002). The incidence of CVD was significantly higher in the post-Tx BMI ≥30 kg/m² group than in the BMI <30 kg/m² group (50% vs 11%; P = .023). There were no differences in surgical operating time, intraoperative blood loss, or perioperative complications between the obese and non-obese groups.

CONCLUSION

Pre-Tx BMI ≥25 kg/m² may be a risk factor for allograft rejection and graft loss. Post-Tx BMI should be <25 kg/m² to reduce the risk for PTDM.

A Novel Method of CD31-Combined ABO Carbohydrate Antigen Microarray Predicts Acute Antibody-Mediated Rejection in ABO-Incompatible Kidney Transplantation

Isohemagglutinin assays employing red blood cells (RBCs) are the most common assays used to measure antibody titer in ABO-incompatible kidney transplantation (ABOi KTx). However, ABO antigens expressed on RBCs are not identical to those of kidney and antibody titers do not always correlate with clinical outcome. We previously reported that CD31 was the main protein linked to ABO antigens on kidney endothelial cells (KECs), which was different from those on RBCs. We developed a new method to measure antibody titer using a microarray of recombinant CD31 (rCD31) linked to ABO antigens (CD31-ABO microarray). Mass spectrometry analysis suggested that rCD31 and native CD31 purified from human kidney had similar ABO glycan. To confirm clinical use of CD31-ABO microarray, a total of 252 plasma samples including volunteers, hemodialysis patients, and transplant recipients were examined. In transplant recipients, any initial IgG or IgM antibody intensity >30,000 against the donor blood type in the CD31-ABO microarray showed higher sensitivity, specificity, positive predictive value, and negative predictive value of AABMR, compared to isohemagglutinin assays. Use of a CD31-ABO microarray to determine antibody titer specifically against ABO antigens expressed on KECs will contribute to precisely predicting AABMR or preventing over immunosuppression following ABOi KTx.

A case of bronchiolitis obliterans after living-donor renal transplantation

We herein report the case of a 20 year-old-man who developed bronchiolitis obliterans after living-donor renal transplantation. The patient presented with dyspnea on exertion and wheezing two years after renal transplantation, and spirometry showed an obstructive pattern. Surgical lung biopsy revealed subepithelial fibrosis that constricted and obstructed the intrabronchiolar space. Based on these findings, the patient was diagnosed with bronchiolitis obliterans. He was prescribed bronchodilators and azithromycin, and he achieved stable respiratory function for two years. The differential diagnosis of respiratory symptoms after renal transplantation includes opportunistic infection and drug-induced lung injury; however, bronchiolitis obliterans should also be considered.

Inguinal Herniation After Living Donor Kidney Transplantation: A Case Report

A 68-year-old male patient received a living donor kidney transplantation 8 years earlier for end-stage kidney disease secondary to IgA nephropathy. His post-transplantation follow-up had been routinely performed with laboratory examinations, ultrasound, and computed tomography (CT). His kidney graft function had been excellent and stable, as shown by a baseline serum creatinine level of 1.0 mg/dL. At referral, regular follow-up ultrasound and CT showed allograft hydroureteronephrosis. He did not have any complaints, but his physical examination revealed right inguinal bulging that was 3.5 × 3.5 cm. Abdominal enhanced CT revealed transplant allograft hydroureteronephrosis due to ipsilateral herniation of ureteroneocystostomy into the right inguinal canal. His serum creatinine level was slightly elevated (1.1 mg/dL). Then, he underwent an open right inguinal hernia repair. Paraperitoneal allograft hydroureteronephrosis and bladder herniation was confirmed at surgery, and hernioplasty with polypropylene mesh reinforcement was successfully performed. The postoperative course was uneventful. He was discharged on the seventh day after surgery. Six weeks after surgery, CT revealed disappearance of allograft hydroureteronephrosis and no sign of inguinal hernia recurrence with the serum creatinine stable at 1.0 mg/dL. Transplant ureteral obstruction due to inguinal hernia is a rare complication after kidney transplantation. However, transplant ureter or bladder herniation should be considered in the differential diagnosis of graft hydroureteronephrosis for preventing allograft loss.

9-ING-41, a small molecule inhibitor of GSK-3beta, potentiates the effects of anticancer therapeutics in bladder cancer

Glycogen synthase kinase-3 beta (GSK-3β), a serine/threonine kinase, has been identified as a potential therapeutic target in human bladder cancer. In the present study, we investigated the antitumor effect of a small molecule GSK-3β inhibitor, 9-ING-41, currently in clinical studies in patients with advanced cancer, in bladder cancer cell lines. We found that treatment with 9-ING-41 leads to cell cycle arrest, autophagy and apoptosis in bladder cancer cells. The autophagy inhibitor chloroquine potentiated the antitumor effects of 9-ING-41 when tested in combination studies. Our findings also demonstrate that 9-ING-41 enhanced the growth inhibitory effects of gemcitabine or cisplatin when used in combination in bladder cancer cells. Finally, we found that 9-ING-41 sensitized bladder cancer cells to the cytotoxic effects of human immune effector cells. Our results provide a rationale for the inclusion of patients with advanced bladder cancer in clinical studies of 9-ING-41.

Analysis of the prevalence of systemic de novo thrombotic microangiopathy after ABO-incompatible kidney transplantation and the associated risk factors

OBJECTIVES

To analyze the prevalence of systemic de novo thrombotic microangiopathy in ABO-incompatible kidney transplantation and risk factors associated with this condition.

METHODS

A total of 201 patients who received living-donor kidney transplantation (114 patients with ABO-identical kidney transplantation and 87 patients with ABO-incompatible kidney transplantation) were retrospectively analyzed. Systemic de novo thrombotic microangiopathy was diagnosed clinically according to the presence of thrombocytopenia with microangiopathic hemolytic anemia and pathological findings of thrombotic microangiopathy. Anti-A and anti-B antibodies were purified from human plasma, and these antibodies' bindings to human kidney were investigated in vitro.

RESULTS

ABO-incompatible kidney transplantation was a significant risk factor of systemic de novo thrombotic microangiopathy (odds ratio 55.9, 95% CI 1.8-8.9, P < 0.001) after transplantation. Multivariate logistic regression analysis showed that non-use of mycophenolate mofetil, pretreatment immunoglobulin G antibody titer ≥64-fold and pretransplant immunoglobulin M antibody titer ≥16-fold were significant risk factors for systemic de novo thrombotic microangiopathy in ABO-incompatible kidney transplantation. Microvascular inflammation of 1-h post-transplant biopsy could be observed more frequently in thrombotic microangiopathy patients than in non-thrombotic microangiopathy patients. Anti-A and anti-B antibodies purified from human plasma showed a strong in vitro reaction against human kidney when the antibody titer was ≥16-fold.

CONCLUSIONS

Antibody titer should be decreased to ≤16-fold until the day of ABO-incompatible kidney transplantation by desensitization therapy including mycophenolate mofetil. The 1-h biopsy results might help to diagnose systemic de novo thrombotic microangiopathy.

Efficacy and safety of ribavirin therapy for chronic hepatitis E after kidney transplantation

Hepatitis E virus (HEV) infection has been recognized as an acute condition. However, recent reports have shown that immunocompromised patients, such as those receiving solid-organ transplantation, can develop chronic hepatitis with HEV infection. We report two cases of chronic hepatitis E after kidney transplantation (KT) who were successfully treated with ribavirin monotherapy. Several years after KT, both patients had sustained elevations in the levels of liver enzymes for a period of more than 6 months. Both patients had HEV infection, genotype 3a. Histological studies showed infiltration of inflammatory cells without fibrosis. Treatment included ribavirin monotherapy at a dosage of 600 mg daily for 3 months. One month after therapy initiation, HEV-RNA turned to negative, and remained negative at 24 weeks after ribavirin therapy without severe complications. Although the treatment of chronic hepatitis E is not fully established, ribavirin therapy can be a safe and effective treatment for chronic hepatitis E.

Transgenic expression of human CD47 reduces phagocytosis of porcine endothelial cells and podocytes by baboon and human macrophages

BACKGROUND

Our initial studies utilizing a galactosyl-α1-3-galactosyltransferase gene knockout (GalTKO) pig-to-baboon renal transplant model demonstrated that the early development of nephrotic syndrome has been a significant obstacle to the long-term survival of baboon recipients. We have recently documented that sphingomyelin phosphodiesterase-3 (SMPDL3b) and CD80 expressed on podocytes in porcine kidney grafts contribute to this complication. We have hypothesized that one regulator of immune function is CD47 and that incompatibilities in CD47 between pig and baboon could potentially affect macrophage function, increasing the susceptibility of the kidney grafts to immunologically induced injury.

METHODS

In order to address this hypothesis in vitro, we isolated and cultured porcine podocytes and ECs from GalTKO alone, human CD47 (hCD47)/hCD55 expressing transgenic (Tg) GalTKO swine, and GalTKO hCD46/hCD55 Tg swine along with baboon or human macrophages.

RESULTS

We found that baboon macrophages phagocytosed porcine ECs in a similar manner to human macrophages, and this response was significantly reduced when porcine ECs and podocytes expressed hCD47/hCD55 but not hCD46/hCD55 without hCD47. Furthermore, masking hCD47 by anti-hCD47 antibody on hCD47/hCD55Tg ECs restored phagocytosis. These results are consistent with the hypothesis that CD47 incompatibility plays an important role in promoting macrophage phagocytosis of endogenous cells from the transplanted kidney.

CONCLUSIONS

The similar levels of phagocytosis of porcine cells by baboon and human macrophages suggest that the expression of hCD47Tg on glomerular cells in donor porcine kidneys may prove to be a key strategy for preventing proteinuria following kidney xenotransplantation in a pig-to-human as well as a pig-to-baboon model.

Limited significance of repeated long-term radiological and hormonal examination in nonfunctioning adrenal incidentalomas

Purpose:

The purposes of the present study were to evaluate growth rate of nonfunctioning adrenal incidentalomas (AIs) and their development to hormonal hypersecretion on follow-up.

Materials and methods:

A retrospective study was conducted from the electronic medical records. A total of 314 patients were diagnosed with adrenal tumors between 2000 and 2016. After excluding patients who had overt adrenal endocrine disorders or whose adrenal tumors were clinically diagnosed as metastatic malignancies, we investigated 108 patients with nonfunctioning AIs including characteristics, the treatment, the way of follow-up and pathology.

Results:

Fifteen patients received immediate adrenalectomy because of the initial tumor size or patient's preference. Pathological examination revealed malignancy in 2 patients. In the remaining 93 patients, radiological examinations were performed periodically. Tumor enlargement of ≥ 1.0cm was observed in 8.6% of the patients who were followed up as nonfunctioning AIs with a median follow-up period of 61.5 months (range: 4-192). Eleven patients underwent adrenalectomy. On the pathological examinations, all of the tumors, which showed a size increase, were diagnosed as benign tumors. Regarding the followed up patients without adrenalectomy, only 2.4% of the patients had tumor enlargement during the prolonged follow-up. Furthermore, none of the patients developed hormonal hypersecretion or clinical signs such as obesity, glucose intolerance or poorly controlled hypertension.

Conclusions:

Tumor enlargement of AIs did not correlate with malignancy. The value of repeat radiological and hormonal examinations may be limited in the long-term follow-up of patients whose AIs are not enlarged.

Abstract 4812: 9-ING-41, a novel inhibitor of glycogen synthase kinase-3beta (GSK-3β), is active as a single agent and within combination therapies in bladder cancer cell lines

Glycogen synthase kinase-3beta (GSK-3β) is a serine/threonine protein kinase that has been established as a therapeutic target in a broad spectrum of human malignancies. We have previously identified aberrant GSK-3β nuclear expression in bladder cancer (BC), and demonstrated that GSK-3β positively regulated BC cell survival and proliferation. Our objective was to evaluate the antitumor effects of the clinically viable agent 9-ING-41, a maleimide-based ATP-competitive GSK-3 inhibitor, which has broad spectrum antitumor activity and marked activity in reversing chemoresistance in a variety of pre-clinical models of human cancers. We used flow cytometry, Western immunoblotting, quantitative RT-PCR, BrDU incorporation and MTS assays to examine antitumor activity of 9-ING-41 in BC (T24, HT1376, RT4 cell lines). Additionally, we studied combination therapy of 9-ING-41 with gemcitabine and cisplatin, standard agents used for the treatment of patients with advanced BC, with cabozantinib, a multi kinase inhibitor, and with chloroquine, an autophagy inhibitor. A dose-dependent decrease in cancer cell proliferation was observed by MTS assay and BrdU incorporation assay with GI50 0.7μM (T24), 4.7 μM(HT1376), 2.2μM(RT4). Treatment with 9-ING-41 induced prominent cell cycle arrest (predominantly G2 arrest) in BC cells. Expression of cell cycle related proteins, including Cyclin D, and anti-apoptotic proteins, such as XIAP and Bcl-2, were significantly decreased as detected by Western immunoblotting and real time RT-PCR. Treatment with 9-ING-41 significantly potentiated the growth inhibitory effect of cisplatin and gemcitabine in cultured cells. In addition, combination therapy with 9-ING-41 and cabozantinib or chloroquine, significantly potentiated the effect of either single agent. Our data proved that a single treatment using 9-ING-41 is effective in BC cells. Combination treatment of 9-ING-41 with standard chemotherapeutic drugs or novel agents may provide a new therapeutic approaches in BC. These data provide a rational for the inclusion of patients with advanced BC in clinical studies of 9-ING-41.

Citation Format: Hiroo Kuroki, Tsutomu Anraku, Vladimir Bilim, Masayuki Tasaki, Daniel Schmitt, Andrew Mazer, Francis J. Giles, Andrey Ugolkov, Yoshihiko Tomita. 9-ING-41, a novel inhibitor of glycogen synthase kinase-3beta (GSK-3β), is active as a single agent and within combination therapies in bladder cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4812.

Retrospective Analysis to Determine the Optimal Timing to Discontinue Continuous Antibiotic Prophylaxis in Patients with Primary Vesicoureteral Reflux

BACKGROUND

The management of febrile urinary tract infection (fUTI) in patients with vesicoureteral reflux (VUR) is crucial to prevent renal scarring. Continuous antibiotic prophylaxis (CAP) is the most widely used initial treatment for VUR. However, the optimal duration of CAP is still unclear. We aimed to clarify an appropriate patient population and the optimal timing to discontinue CAP.

METHODS

We reviewed the records of 247 patients with primary VUR between January 2000 and December 2015. Seventy-two patients who discontinued CAP despite persistent VUR were enrolled. Kaplan-Meier method and Cox proportional hazard model was used in statistical analysis.

RESULTS

Following the discontinuation of CAP, fUTI developed in 25 patients after a median of 9 months (range 0-81). VUR resolved spontaneously in 9 out of 47 patients without recurrence during follow-up. Multivariate analysis showed bilateral VUR and duration of CAP of less than 1 year after the last fUTI were significant risk factors for recurrence.

CONCLUSION

Among the risk factors examined, patients administered CAP for less than 1 year after the last fUTI and those with bilateral VUR had significantly more frequent recurrence. Our study suggests that the administration of CAP for more than 1 year after the last fUTI is beneficial in avoiding recurrent fUTI.

Upregulation of CD80 on glomerular podocytes plays an important role in development of proteinuria following pig-to-baboon xeno-renal transplantation - an experimental study

We have previously reported that co-transplantation of the kidney with vascularized donor thymus from α-1,3-galactosyltransferase gene knockout pigs with an anti-CD154 with rituximab-based regimen led to improved xenograft survival in baboons with donor-specific unresponsiveness. However, nephrotic syndrome emerged as a complication in which the glomeruli showed mild mesangial expansion with similarities to minimal change disease (MCD) in humans. Since MCD is associated with CD80 expression in glomeruli and elevated urinary excretion, we evaluated a potential role for CD80 in xenograft nephropathy. Study 1 confirmed high urinary CD80 excretion in nephrotic animals with renal xenografts showing CD80 expression in glomeruli. In Study 2, baboons receiving xenografts received CTLA4-Ig once a week from the second postoperative week or no CTLA4-Ig. The non-CTLA4-Ig group developed severe proteinuria with modest mesangial expansion with high urinary excretion of CD80 and documented CD80 expression in glomerular podocytes. All of the recipients in non-CTLA4-Ig groups had to be euthanized before POD 60. In contrast, CTLA4-Ig group showed a marked reduction in proteinuria and survived significantly longer, up to 193 days. These results demonstrate that anti-CD80 targeted therapy represents a promising strategy for reduction of proteinuria following renal xeno-transplantation with improved survival.

Re-evaluating Cut-off Points for the Expansion of Deceased Donor Criteria for Kidney Transplantation in Japan

BACKGROUND

A shortage of donors poses a serious problem for organ transplantation around the world. In response, the concept of the expanded criteria donor (ECD) has been defined to include donors with traditionally less favorable characteristics. That definition has now been accepted and is being applied in kidney transplantation in the United States and Europe. However, the ECD has not yet been defined for deceased donor kidney transplantation in Japan.

PATIENTS AND METHODS

We analyzed data on graft survival and relevant risk factors in patients who received deceased donor kidney transplants through the East Japan Branch of the Japan Organ Transplant network (n = 1051). Recipients were divided into two groups: the standard-function group (estimated glomerular filtration rate [eGFR] ≥20 mL/min/1.73 m²; n = 906) and the poor-function group (eGFR <20 mL/min/1.73 m²; n = 145; Cox proportional hazards regression analysis; P < .0001).

RESULTS

The 10-year survival rate was significantly lower in the poor-function group than in the standard-function group (85.5% vs 22.5%; P < .0001). The two groups differed significantly in recipient and donor risk for graft failure. Recipient risk factors were length of time on dialysis before renal transplantation and incidence of acute rejection after transplantation. Donor risk factors were donor category (heart death), age, history of hypertension, presence of cerebrovascular disease, mean urine output, and donor creatinine level immediately before donor nephrectomy, total ischemic time, and warm ischemic time.

CONCLUSION

Data from deceased donor transplantation should be analyzed in depth to determine which factors influence renal function after transplantation. In addition, ECD standards should be reconsidered for use in a Japanese context.

Acquired Downregulation of Donor-Specific Antibody Production After ABO-Incompatible Kidney Transplantation

The mechanism of long-term B cell immunity against donor blood group antigens in recipients who undergo ABO-incompatible (ABOi) living-donor kidney transplantation (LKTx) is unknown. To address this question, we evaluated serial anti-A and anti-B antibody titers in 50 adult recipients. Donor-specific antibody titers remained low (≤1:4) in 42 recipients (84%). However, antibodies against nondonor blood group antigens were continuously produced in recipients with blood type O. We stimulated recipients' peripheral blood mononuclear cells in vitro to investigate whether B cells produced antibodies against donor blood group antigens in the absence of graft adsorption in vivo. Antibodies in cell culture supernatant were measured using specific enzyme-linked immunosorbent assays (ELISAs). Thirty-five healthy volunteers and 57 recipients who underwent ABO-compatible LKTx served as controls. Antibody production in vitro against donor blood group antigens by cells from ABOi LKTx patients was lower than in the control groups. Immunoglobulin deposits were undetectable in biopsies of grafts of eight recipients with low antibody titers (≤1:4) after ABOi LKTx. One patient with blood type A1 who received a second ABOi LKTx from a type B donor did not produce B-specific antibodies. These findings suggest diminished donor-specific antibody production function in the setting of adult ABOi LKTx.

Tolerance of Vascularized Islet-Kidney Transplants in Rhesus Monkeys

We previously reported that transplantation (Tx) of prevascularized donor islets as composite islet-kidneys (IK) reversed diabetic hyperglycemia in both miniature swine and baboons. In order to enhance this strategy's potential clinical applicability, we have now combined this approach with hematopoietic stem cell (HSC) Tx in an attempt to induce tolerance in nonhuman primates. IKs were prepared by isolating islets from 70% partial pancreatectomies and injecting them beneath the autologous renal capsule of five rhesus monkey donors at least 3 months before allogeneic IK Tx. HSC Tx was performed after mobilization and leukapheresis of the donors and conditioning of the recipients with total body irradiation, T cell depletion, and cyclosporine. One IK was harvested for histologic analysis and four were transplanted into diabetic recipients. IK Tx was performed either 20-22 (n = 3) or 208 (n = 1) days after HSC Tx. All animals accepted IKs without rejection. All recipients required >20 U/day insulin before IK Tx to maintain <200 mg/dL, whereas after IK Tx, three animals required minimal doses of insulin (1-3 U/day) and one animal was insulin free. These results constitute a proof-of-principle that this IK tolerance strategy may provide a cure for both end-stage renal disease and diabetes without the need for immunosuppression.

Successful Second Allogeneic Stem Cell Transplantation From a Sibling Donor for Relapse of Myelodysplastic Syndrome in a Recipient of a Renal Transplant From His Mother: Case Report

There have been few reports on allogeneic stem cell transplantation in patients who have previously undergone solid organ transplantation. The clinical course of such patients is not yet well recognized. Therefore, appropriate immunosuppressive prophylaxis for the rejection of a solid organ graft or for graft-versus-host disease has not yet been established. We present the case of a successful allogeneic stem cell transplantation in a patient who relapsed after a first allogeneic stem cell transplantation for myelodysplastic syndrome and who had previously undergone renal transplantation. The prophylaxis in this case for graft-versus-host disease and rejection of the transplanted kidney was mycophenolate mofetil and tacrolimus. No hyperacute rejection of the transplanted kidney was observed. However, the patient's renal function deteriorated after the cessation of the mycophenolate mofetil and the reduction of the tacrolimus. This deterioration seemed to be due to rejection with humoral immunity of donor lymphocytes, and we were able to control it by resuming the mycophenolate mofetil and local graft irradiation.

Role of Bone Marrow Maturity, Insulin-Like Growth Factor 1 Receptor, and Forkhead Box Protein N1 in Thymic Involution and Rejuvenation

Thymic involution is associated with age-related changes of the immune system. Utilizing our innovative technique of transplantation of a thymus as an isolated vascularized graft in MHC-inbred miniature swine, we have previously demonstrated that aged thymi are rejuvenated after transplantation into juvenile swine. Here we have studied the role of insulin-like growth factor (IGF) and forkhead-box protein-N1 (FOXN1) as well as bone marrow (BM) in thymic rejuvenation and involution. We examined thymic rejuvenation and involution by means of histology and flow cytometry. Thymic function was assessed by the ability to induce tolerance of allogeneic kidneys. Aged thymi were rejuvenated in a juvenile environment, and successfully induced organ tolerance, while juvenile thymi in aged recipients involuted and had a limited ability to induce tolerance. However, juvenile BM inhibited the involution process of juvenile thymi in aged recipients. An elevated expression of both FOXN1 and IGF1 receptors (IGF-1R) was observed in juvenile thymi and rejuvenated thymi. Juvenile BM plays a role in promoting the local thymic milieu as indicated by its ability to inhibit thymic involution in aged animals. The expression of FOXN1 and IGF-1R was noted to increase under conditions that stimulated rejuvenation, suggesting that these factors are involved in thymic recovery.

Corepressive function of nuclear receptor coactivator 2 in androgen receptor of prostate cancer cells treated with antiandrogen

BACKGROUND

Recruitment of cofactors in the interaction of the androgen receptor (AR) and AR ligands plays a critical role in determining androgenic/antiandrogenic effects of the AR ligand on signaling, but the functions of key cofactors, including nuclear receptor coactivator (NCOA), remain poorly understood in prostate cancer cells treated with AR ligands.

METHODS

We examined prostate cancer cell lines LNCaP and VCaP expressing mutated and wild-type ARs, respectively, to clarify the significance of NCOAs in the effect of antiandrogens. Hydroxyflutamide showed antagonistic activity against VCaP and an agonistic effect on LNCaP. Bicalutamide served as an antagonist for both. We analyzed mRNA transcription and protein expression of NCOAs in these cells pretreated with dihydrotestosterone and thereafter treated with the mentioned antiandrogens. Transcriptional silencing of candidate NCOAs and AR was performed using small interfering RNA (siRNA). Cell proliferation was evaluated with MTT assay.

RESULTS

LNCaP treated with bicalutamide showed an about four-fold increase in the expression of NCOA2 mRNA compared to those pretreated with dihydrotestosterone alone (P <0.01). In VCaP pretreated with dihydrotestosterone, transcriptions of NCOA2 and NCOA7 were slightly increased with bicalutamide (1.96- and 2.42-fold, respectively) and hydroxyflutamide (1.33-fold in both). With Western blotting, the expression of NCOA2 protein also increased in LNCaP cells treated with bicalutamide compared with that in control cells pretreated with dihydrotestosterone alone. Following silencing with siRNA for NCOA2, PSA levels in media with LNCaP receiving bicalutamide were elevated compared with those in non-silencing controls (101.6 ± 4.2 vs. 87.8 ± 1.4 ng/mL, respectively, P =0.0495). In LNCaP cells treated with dihydrotestosterone and bicalutamide, NCOA2-silencing was associated with a higher proliferation activity compared with non-silencing control and AR-silencing.

CONCLUSION

NCOA2, which has been thought to be recruited as a coactivator, possibly plays a corepressive role in AR of prostate cancer cells when treated with antiandrogens, suggesting its potential as a therapeutic target.

Adoptive Transfer of Renal Allograft Tolerance in a Large Animal Model

Our recent studies in an inbred swine model demonstrated that both peripheral and intra-graft regulatory cells were required for the adoptive transfer of tolerance to a second, naïve donor-matched kidney. Here, we have asked whether both peripheral and intra-graft regulatory elements are required for adoptive transfer of tolerance when only a long-term tolerant (LTT) kidney is transplanted. Nine highly-inbred swine underwent a tolerance-inducing regimen to prepare LTT kidney grafts which were then transplanted to histocompatible recipients, with or without the peripheral cell populations required for adoptive transfer of tolerance to a naïve kidney. In contrast to our previous studies, tolerance of the LTT kidney transplants alone was achieved without transfer of additional peripheral cells and without strategies to increase the number/potency of regulatory T cells in the donor. This tolerance was systemic, since most subsequent, donor-matched challenge kidney grafts were accepted. These results confirm the presence of a potent tolerance-inducing and/or tolerance-maintaining cell population within LTT renal allografts. They suggest further that additional peripheral tolerance mechanisms, required for adoptive transfer of tolerance to a naïve donor-matched kidney, depend on peripheral cells that, if not transferred with the LTT kidney, require time to develop in the adoptive host.

Rat-to-Chinese tree shrew heart transplantation is a novel small animal model to study non-Gal-mediated discordant xenograft humoral rejection

Since α-1,3-galactosyltransferase knockout (GalT-KO) pigs became available, there has been an increasing interest in non-Gal natural antibody (nAb)-mediated xenograft rejection. To better understand mechanisms of non-Gal nAb-mediated rejection, a simple small animal model without gene manipulation would be extremely valuable. Here, we tested whether the Chinese tree shrew (CTS), which is a small-sized mammal that is phylogenetically close to primates, could serve as a model for discordant xenograft rejection.

METHODS

Study 1: Expression of α-Gal antigens in hearts and kidneys of CTSs and rats was assessed by IB4 lectin binding. Presence of anti-Gal and anti-non-Gal IgM and IgG nAb in CTS sera was tested by FACS using Gal+ and GalTKO PBMC as well as BSA-ELISA. Study 2: Rat hearts were transplanted into CTS recipients (group 1, n = 7), and CTS hearts were transplanted in rats [n = 10; seven received no immunosuppression (group 2) and three received FK506 + leflunomide (group 3)].

RESULTS

Study 1: Both CTSs and rats had α-Gal expression in hearts and kidneys. ELISA showed CTSs do not have anti-Gal nAb, and flow cytometry indicated CTSs have anti-non-Gal IgM and IgG nAb in serum. Study 2: Rat hearts in CTSs were uniformly rejected within 35 mins, while CTS hearts in rats continued beating until day 5 without immunosuppression, and up to day 8 with immunosuppression.

CONCLUSION

Rat-to-CTS heart transplantation is a discordant xenotransplant model, CTS-to-Rat heart transplantation is a concordant xenotransplant model. CTSs are valuable small animals to study mechanisms and strategies to avoid non-Gal nAb-mediated xenograft rejection.

Datasets from label-free quantitative proteomic analysis of human glomeruli with sclerotic lesions

Human glomeruli with intermediate (i-GS) and advanced (GS) sclerotic lesions as well as the normal control (Nor) were captured from laser microdissection, digested by trypsin and subjected to shotgun LC-MS/MS analysis (LTQ-Orbitrap XL). The label-free quantification was performed using the Normalized Spectral Index (SI N ) to assess the relative molar concentration of each protein identified in a sample. All the experimental data are shown in this article. The data is associated to the research article submitted to Journal of Proteomics [1].

High incidence of xenogenic bone marrow engraftment in pig-to-baboon intra-bone bone marrow transplantation

Previous attempts of α-1,3-galactocyltransferase knockout (GalTKO) pig bone marrow (BM) transplantation (Tx) into baboons have demonstrated a loss of macro-chimerism within 24 h in most cases. In order to achieve improved engraftment with persistence of peripheral chimerism, we have developed a new strategy of intra-bone BM (IBBM) Tx. Six baboons received GalTKO BM cells, with one-half of the cells transplanted into the bilateral tibiae directly and the remaining cells injected intravenously (IBBM/BM-Tx) with a conditioning immunosuppressive regimen. In order to assess immune responses induced by the combined IBBM/BM-Tx, three recipients received donor SLA-matched GalTKO kidneys in the peri-operative period of IBBM/BM-Tx (Group 1), and the others received kidneys 2 months after IBBM/BM-Tx (Group 2). Peripheral macro-chimerism was continuously detectable for up to 13 days (mean 7.7 days; range 3-13) post-IBBM/BM-Tx and in three animals, macro-chimerism reappeared at days 10, 14 and 21. Pig CFUs, indicating porcine progenitor cell engraftment, were detected in the host BM in four of six recipients on days 14, 15, 19 and 28. In addition, anti-pig unresponsiveness was observed by in vitro assays. GalTKO/pCMV-kidneys survived for extended periods (47 and 60 days). This strategy may provide a potent adjunct for inducing xenogeneic tolerance through BM-Tx.

The rejuvenating effects of leuprolide acetate on the aged baboon's thymus

BACKGROUND

We have previously demonstrated that the juvenile thymus plays an essential role in tolerance induced by both renal transplantation and a short course of calcineurin inhibitors. Aged thymi have a decreased ability to induce tolerance. Luteinizing hormone-releasing hormone (LHRH) is known to pharmacologically rejuvenate the thymus in rodents. In order to develop a clinically applicable regimen of transplantation tolerance in adults, we sought to determine if thymic rejuvenation would occur with LHRH agonism in non-human primates.

METHODS AND RESULTS

Thymic rejuvenation was evaluated by magnetic resonance imaging (MRI), histology, as well as in-vitro cellular and molecular tests. Four aged male hamadryas baboons underwent subcutaneous injection of a 3-month depot of Lupron (11.25mg; LI) and were followed for 3 months. Thymi increased volumetrically by MRI. After LI, thymic cellularity markedly increased within the cortical and medullary thymus. Additionally, a significant increase in the CD4(+)/CD45RA(hi+) population in the peripheral blood occurred for 50 days after LI, and flow cytometry of thymic tissue revealed a large increase in the percentage of CD4(+)/CD8(+) cells. TREC assay corroborated enhancement in thymic function.

CONCLUSION

These data indicate that LI is associated with thymic rejuvenation in baboons, and further confirm that extrinsic factors play an important role in thymic rejuvenation in a non-human primate model.

Effect of donor-recipient age difference on long-term graft survival in living kidney transplantation

PURPOSE

We aimed to examine the influence of donor age on living-donor kidney transplantation (KTx), particularly with regard to long-term graft survival in young recipients with aged kidney grafts.

METHODS

Between 1988 and 2012, 287 living-donor KTxs were performed in our center. The recipients were divided into 3 groups according to age in years: under 30 (young), 30-49 (middle-aged), and over 50 (old). The data regarding the influence of kidneys from donors aged over 50 years were retrospectively analyzed.

RESULTS

Graft survival at 1, 5, 10, and 15 years was 94.7, 94.7, 90.2, and 75.2%, respectively, in young recipients who received grafts from donors aged under 50 years, and 96.4, 91.9, 65.4, and 41.4%, respectively, in young recipients who received grafts from donors aged over 50 years (P = 0.023). In contrast, there were no significant differences regarding graft survival and donor age in the middle-aged and old recipient groups. Multivariate analysis revealed that young recipient and rejection episode were significant predictors of graft loss in transplantation from older donors. Histological examination revealed significant age-related changes in the grafts before transplant and a significant higher rate of glomerular hypertrophy at the 1-month protocol biopsy in young recipients with aged kidney grafts.

CONCLUSIONS

Kidney grafts from older living donors affected long-term graft survival in young recipients. In addition to the damage from rejection, aged kidney grafts, which have less nephron mass, may have a limited capacity to appropriately respond to increases in physiological or metabolic demands of young recipients, leading to a greater reduction in renal function.

Rituximab treatment prevents the early development of proteinuria following pig-to-baboon xeno-kidney transplantation

We previously reported life-supporting α1,3-galactosyltransferase knockout (GalTKO) thymokidney xenograft survival of >2 months in baboons. However, despite otherwise normal renal function, recipients developed proteinuria with morphologic changes (podocyte effacement), a condition that presents a major obstacle to long-term studies in this model. A recent clinical study showed that rituximab therapy after allogeneic transplant prevented proteinuria possibly associated with loss of sphingomyelin phosphodiesterase acid-like 3b (SMPDL-3b). Here, we demonstrate that rituximab prevents the disruption of pig podocytes in an SMPDL-3b-dependent manner in vitro and the early development of proteinuria after xenogeneic kidney transplantation in baboons. Immunofluorescence showed SMPDL-3b expression in pig glomerular epithelium; immunoprecipitation demonstrated rituximab binding to SMPDL-3b in glomeruli. Culture of isolated pig podocytes with naive baboon sera, which has preformed antipig natural antibodies, reduced SMPDL-3b expression, disrupted podocyte morphology, and decreased podocyte proliferation, whereas pretreatment with rituximab prevented these effects. Six baboons received rituximab before transplantation to deplete B cells and again in the peri-transplant period; 18 baboons treated only before transplantation served as historical controls. The onset of post-transplant proteinuria was significantly delayed in a B cell-independent manner in the animals that received peri-transplant rituximab treatment. Although further optimization of this protocol is required, these data provide intriguing clues to the mechanisms of post-transplant proteinuria in xenogeneic kidney transplantation and a potential strategy for its prevention.

Induction of cardiac allograft tolerance across a full MHC barrier in miniature swine by donor kidney cotransplantation

We have previously shown that tolerance of kidney allografts across a full major histocompatibility complex (MHC) barrier can be induced in miniature swine by a 12-day course of high-dose tacrolimus. However, that treatment did not prolong survival of heart allografts across the same barrier. We have now tested the effect of cotransplanting an allogeneic heart and kidney from the same MHC-mismatched donor using the same treatment regimen. Heart allografts (n = 3) or heart plus kidney allografts (n = 5) were transplanted into MHC-mismatched recipients treated with high-dose tacrolimus for 12 days. As expected, all isolated heart allografts rejected by postoperative day 40. In contrast, heart and kidney allografts survived for >200 days with no evidence of rejection on serial cardiac biopsies. Heart/kidney recipients lost donor-specific responsiveness in cell-mediated lympholysis and mixed-lymphocyte reaction assays, were free of alloantibody and exhibited prolonged survival of donor, but not third-party skin grafts. Late (>100 days) removal of the kidney allografts did not cause acute rejection of the heart allografts (n = 2) and did not abrogate donor-specific unresponsiveness in vitro. While kidney-induced cardiac allograft tolerance (KICAT) has previously been demonstrated across a Class I disparity, these data demonstrate that this phenomenon can also be observed across the more clinically relevant full MHC mismatch. Elucidating the renal element(s) responsible for KICAT could provide mechanistic information relevant to the induction of tolerance in recipients of isolated heart allografts as well as other tolerance-resistant organs.

The induction of tolerance of renal allografts by adoptive transfer in miniature swine

Our previous in vitro data have demonstrated that regulatory mechanisms are involved in tolerance of class I-mismatched renal allografts in miniature swine treated with 12 days of high dose Cyclsporin A. In this study, we attempted to induce tolerance of class I-mismatched kidneys by adoptive transfer of cells and/or kidneys from long-term tolerant animals. Fifteen SLA(dd) miniature swine received 1.5 Gy whole body irradiation and class I-mismatched (SLA(gg) ) kidneys from naïve pigs with or without cotransplanted kidneys and/or adoptively transferred cells from long-term tolerant (LTT) SLA(dd) recipients of SLA(gg) grafts. In addition, three SLA(dd) miniature swine received class I mismatched kidney with adoptively transferred cells from LTT SLA(dd) recipients. Naïve kidneys transplanted without a LTT kidney were rejected within 9 days. All recipients of naive kidneys along with cells and kidney grafts from LTT animals showed markedly prolonged survival of the naive renal grafts (day 28, >150 and >150 days). These studies suggest that (1) tolerated kidneys have potent regulatory effects and (2) cells from LTT animals infused in conjunction with kidney grafts augment these regulatory effects. To our knowledge, these studies represent the first demonstration of successful adoptive transfer of tolerance in large animals.

Clinical Significance of the Pharmacological Efficacy of Tacrolimus Estimated by the Lymphocyte Immunosuppressant Sensitivity Test (LIST) Before and After Renal Transplantation

The lymphocyte immunosuppressant sensitivity test (LIST) with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay procedure can predict the pharmacological efficacy of immunosuppressive agents. A previous study reported the pharmacological efficacy of tacrolimus evaluated by LIST just before renal transplantation significantly correlated with the incidence of acute rejection episodes. However, the pharmacological efficacy of tacrolimus has not been estimated after renal transplantation. Therefore, the present study evaluated the pharmacological efficacy of tacrolimus by LIST using the MTT assay procedure before and 1, 3, and 12 months after transplantation in 17 renal transplant recipients that received tacrolimus-based immunosuppressive therapy. The tacrolimus pharmacological efficacies before and after the procedure were also compared with incidence of acute rejection and cytomegalovirus (CMV) infection episodes. The individual values of tacrolimus 50% inhibition of lymphocyte proliferation (IC50) varied widely before transplantation, and the mean value of the IC50 was 126.4 ± 337.7 ng/ml. The patients were divided into two groups according to the tacrolimus IC50 values evaluated before transplantation. The rate of acute rejection episodes in the tacrolimus high-sensitivity group was significantly lower than that in the tacrolimus low-sensitivity group (p = 0.005). The tacrolimus IC50 deviation between patients expanded further at one and three months after surgery. However, the sensitivity deviation almost converged at 1 year after surgery. Moreover, the pharmacological efficacy of tacrolimus evaluated at 1, 3, and 12 months after transplantation did not significantly correlate with the incidence of acute rejection episodes. The pharmacological efficacies of tacrolimus evaluated at both before and after surgery were not significantly correlated with the episodes of CMV infection. These findings suggest that the pharmacological efficacy of tacrolimus evaluated with LIST before surgery is a useful biomarker for predicting the occurrence of acute allograft rejection in renal transplantation.

Effect of pre-existing anti-diphtheria toxin antibodies on T cell depletion levels following diphtheria toxin-based recombinant anti-monkey CD3 immunotoxin treatment

Diphtheria toxin (DT)-based anti-CD3 immunotoxins have clinical relevance in numerous applications including autoimmune disease therapies and organ transplantation tolerance protocols. Pre-existing anti-DT antibodies acquired either by vaccination against diphtheria toxin or infections with C. diphtheriae may interfere or inhibit the function of these anti-CD3 immunotoxins. Previously, a full-length anti-rhesus monkey CD3 immunotoxin, FN18-CRM9, was shown to be less effective at depleting circulating T cells in animals with pre-existing anti-DT antibody titers than in animals without antibodies, and subsequent doses were ineffective. In this study, the T cell depletion function of a truncated DT based recombinant anti-monkey CD3 immunotoxin, A-dmDT390-scfbDb (C207), as part of a reduced intensity conditioning regimen prior to hematopoietic cell transplantation, was compared between two groups of monkeys: those with and without pre-existing anti-diphtheria titers. T cell depletion was comparable in both groups of monkeys, and therefore appeared to be unaffected by the presence of moderate levels of pre-existing anti-diphtheria antibodies.

Comparative Study of the Cellular Pharmacodynamics of Tacrolimus in Renal Transplant Recipients Treated with and without Basiliximab

Basiliximab is a recently developed immunosuppressive agent for the prevention of acute allograft rejection in renal transplant recipients. The combination use of basiliximab and a calcineurin inhibitor was suggested to be more effective in comparison to immunosuppressive therapy using calcineurin inhibitor without basiliximab. Cyclosporine has been generally administered with basiliximab for renal transplant recipients. However, in cases of tacrolimus-based immunosuppressive regimen, the clinical efficacy and safety of combined use of tacrolimus and basiliximab remains to be elucidated. This study evaluated the tacrolimus pharmacological efficacy using a lymphocyte immunosuppressant sensitivity test (LIST) with MTT assay procedures in 16 cases of renal transplant recipients treated by tacrolimus without basiliximab and in 13 cases treated by tacrolimus in combination with basiliximab. The rate of acute rejection episodes in the recipients treated with tacrolimus plus basiliximab was 1/13 (7.7%), whereas the rate in the recipients treated with tacrolimus without basiliximab was 6/16 (37.5%). The recipients were divided into two groups according to their peripheral blood mononuclear cell (PBMC) sensitivity to tacrolimus [i.e., including a tacrolimus high sensitivity group (IC50 <1.0 ng/ml) and a low sensitivity group (IC50 >1.0 ng/ml). In the recipients treated with tacrolimus without basiliximab, the rate of acute rejection episodes in the tacrolimus high sensitivity group was 1/10 (10.0%), which was significantly lower than the rate in the low sensitivity group of 5/6 (83.3%; p = 0.008). The incidence of cytomegalovirus infection was not significantly different between the tacrolimus high and the low sensitivity groups of the recipients treated with tacrolimus with and without basiliximab. Therefore, in the case of selected tacrolimus-based immunosuppressive therapy for renal transplant recipients, the tacrolimus pharmacological efficacy should be evaluated using LIST at a time just before the transplant procedure in order to accurately predict allograft rejection. The data also suggested that low tacrolimus sensitivity recipients should be treated with tacrolimus-based immunosuppressive therapy in combination with basiliximab.