Peritoneal mesenchymal stromal cells (pMSCs) are isolated from peritoneal dialysis (PD) effluent, and treatment with the pMSCs reduces peritoneal membrane injury in rat model of PD. This study was designed to verify the identity of the pMSCs. pMSCs were grown in plastic dishes for 4-7 passages, and their cell surface phenotype was examined by staining with a panel of 242 antibodies. The positive stain of each target protein was determined by an increase in fluorescence intensity as compared with isotype controls in flow cytometrical analysis. Here, we showed that pMSCs predominantly expressed CD9, CD26, CD29, CD42a, CD44, CD46, CD47, CD49b, CD49c, CD49e, CD54, CD55, CD57, CD59, CD63, CD71, CD73, CD81, CD90, CD98, CD147, CD151, CD200, CD201, β2-micoglobulin, epithelial growth factor receptor, human leukocyte antigen (HLA) class 1, and, to a lesser extent, CD31, CD45RO, CD49a, CD49f, CD50, CD58, CD61, CD105, CD164, and CD166. These cells lacked expression of most hematopoietic markers such as CD11b, CD14, CD19, CD34, CD40, CD80, CD79, CD86, and HLA-DR. There was 38.55% difference in the expression of 83 surface proteins between bone marrow (BM)-derived MSCs and pMSCs, and 14.1% in the expression of 242 proteins between adipose tissue (AT)-derived MSCs and pMSCs. The BM-MSCs but not both AT-MSCs and pMSCs express cytokine receptors (IFNγR, TNFI/IIR, IL-1R, IL-4R, IL-6R, and IL-7R). In conclusion, pMSCs exhibited a typical cell surface phenotype of MSCs, which was not the same as on BM-MSCs or AT-MSCs, suggesting that the pMSCs may represent a different MSC lineage from peritoneal cavity.

Background A long-term of peritoneal dialysis (PD) using a hypertonic PD solution (PDS) leads to patient’s peritoneal membrane (PM) injury, resulting in ultrafiltration failure (UFF) and PD drop-out. Our previous study shows that PD effluent-derived mesenchymal stromal cells (pMSCs) prevent the PM injury in normal rats after repeated exposure of the peritoneal cavity to a PDS. This study was designed to compare the cytoprotection between pMSCs and umbilical cord-derived MSCs (UC-MSCs) in the treatment of both PM and kidney injury in uremic rats with chronic PD. Methods 5/6 nephrectomized (5/6Nx) Sprague Dawley rats were intraperitoneally (IP) injected Dianeal (4.25% dextrose, 10 mL/rat/day) and were treated with pMSCs or umbilical cord (UC)-MSCs (approximately 2 × 10 6 /rat/week, IP). Ultrafiltration was determined by IP injection of 30 mL of Dianeal (4.25% dextrose) with 1.5-h dewell time, and kidney failure by serum creatinine (SCr) and blood urea nitrogen (BUN). The structure of the PM and kidneys was assessed using histology. Gene expression was examined using quantitative reverse transcription PCR, and protein levels using flow cytometric and Western blot analyses. Results We showed a slight difference in the morphology between pMSCs and UC-MSCs in plastic dishes, and significantly higher expression levels of stemness-related genes ( NANOG , OCT4 , SOX2 , CCNA2 , RAD21 , and EXO1 ) and MSCs surface markers (CD29, CD44, CD90 and CD105) in UC-MSCs than those in pMSCs, but no difference in the differentiation to chondrocytes, osteocytes or adipocytes. pMSC treatment was more effective than UC-MSCs in the protection of the MP and remnant kidneys in 5/6Nx rats from PDS-induced injury, which was associated with higher resistance of pMSCs than UC-MSCs to uremic toxins in culture, and more reduction of peritoneal mesothelial cell death by the secretome from pMSCs than from UC-MSCs in response to PDS exposure. The secretome from both pMSCs and UC-MSCs similarly inactivated NOS2 in activated THP1 cells. Conclusions As compared to UC-MSCs, pMSCs may more potently prevent PDS-induced PM and remnant kidney injury in this uremic rat model of chronic PD, suggesting that autotransplantation of ex vivo-expanded pMSCs may become a promising therapy for UFF and deterioration of remnant kidney function in PD patients.

BACKGROUND:Ischemia reperfusion injury (IRI) is the major cause of intestinal damage in clinic. Although either mesenchymal stromal cells (MSCs) or interleukin 37 (IL-37) shows some beneficial roles to ameliorate IRI, their effects are limited. In this study, the preventative effects of IL-37 gene-modified MSCs (IL-37-MSCs) on intestinal IRI are investigated.METHODS:Intestinal IRI model was established by occluding the superior mesenteric artery for 30 minutes and then reperfused for 72 hours in rats. Forty adult male Sprague-Dawley rats were randomly divided into the sham control, IL-37-MSC-treated, MSC-treated, recombinant IL-37- (rIL-37-) treated, and untreated groups. Intestinal damage was assessed by H&E staining. The levels of gut barrier function factors (diamine oxidase and D-Lactate) and inflammation cytokine IL-1β were assayed using ELISA. The synthesis of tissue damage-related NLRP3 inflammasome and downstream cascade reactions including cleaved caspase-1, IL-1β, and IL-18 was detected by western blot. The mRNA levels of proinflammatory mediators IL-6 and TNF-α, which are downstream of IL-1β and IL-18, were determined by qPCR. Data were analyzed by one-way analysis of variance (ANOVA) after the normality test and followed by post hoc analysis with the least significant difference (LSD) test.RESULTS:IL-37-MSCs were able to migrate to the damaged tissue and significantly inhibit intestinal IRI. As compared with MSCs or the rIL-37 monotherapy group, IL-37-MSC treatment both improved gut barrier function and decreased local and systemic inflammation cytokine IL-1β level in IRI rats. In addition, tissue damage-related NLRP3 and downstream targets (cleaved caspase-1, IL-1β, and IL-18) were significantly decreased in IRI rats treated with IL-37-MSCs. Furthermore, IL-1β- and IL-18-related proinflammatory mediator IL-6 and TNF-α mRNA expressions were all significantly decreased in IRI rats treated with IL-37-MSCs.CONCLUSION:The results suggest that IL-37 gene modification significantly enhances the protective effects of MSCs against intestinal IRI. In addition, NLRP3-related signaling pathways could be associated with IL-37-MSC-mediated protection.

Major histocompatibility complex‐II (MHC‐II) plays an important role in graft rejection and class II transactivator (CIITA) is the key regulator for MHC‐II expression. The aim of this study was to determine the efficacy of intragraft inhibition of CIITA in attenuating liver transplant rejection. Three plasmids containing small hairpin RNA (shRNA) against rat CIITA (pCIITA‐shRNA) and one control plasmid of pHK‐shRNA were constructed. In vitro dendritic cell (DC) transfection and liver transfection via portal vein in donor rats (n = 8) by shRNA plasmids were performed to confirm the inhibitory effect of pCIITA‐shRNA on CIITA expression. It showed that expressions of CIITA and MHC‐II were significantly inhibited by pCIITA‐shRNA in both DC in vitro and liver of donor rats in vivo (p < 0.05 vs. control pHK‐shRNA treatment). pCIITA1‐shRNA was proved to be the best inhibitor among three pCIITA‐shRNAs and then used in high‐responder rat liver transplantation model (DA donors‐to‐Lewis recipients). Transplant groups (n = 16/group) include untreated recipients transplanted with donor liver graft pretreated with either saline, or pHK‐shRNA, or pCIITA1‐shRNA. Cyclosporine‐treated (10 mg/kg, im, day 0–7) recipients transplanted with unmodified liver grafts were used as no rejection control. The results showed that the recipient rats survived significantly longer in pCIITA1‐shRNA‐treated group with markedly attenuated liver graft rejection (p < 0.05 vs. saline and pHK‐shRNA‐treated groups). Furthermore, significantly decreased intragraft expressions of CIITA, MHC‐II, IL‐2, and IFN‐γ were found in pCIITA1‐shRNA‐treated group (p < 0.05 vs. saline and pHK‐shRNA‐treated groups). This study suggests that intragraft inhibition of CIITA could be a novel strategy for attenuating graft rejection in liver transplantation. © 2014 Wiley Periodicals, Inc. Microsurgery 35:52–59, 2015.

The cell surface protein CD83 belongs to the immunoglobulin superfamily and is highly expressed on mature dendritic cells. The soluble form of CD83, sCD83, is a potential immune suppressor. In a previous study, recombinant soluble CD83 was expressed in Escherichia coli, resulting in a lack of functional glycosylation. Although eukaryotic cell systems for producing sCD83 offer the advantages of protein processing, folding, and posttranslational modification, these systems are complicated, expensive, and produce low levels of protein. To obtain more efficient expression of sCD83, we expressed human sCD83 fused with fragment crystallizable region of human IgG1 (hIgG1 Fc) in Pichia pastoris. Under the optimal conditions (time of induction, 48 h; inoculum density (OD600), 80; concentration of methanol, 3.0 %; pH 7.0-8.0; concentration of casamino acid, 5.0 %), the purified human sCD83-hIgG1 Fc (hsCD83-Ig) fusion protein existed as dimers at 25-30 mg/L culture. Treatment with PNGase F showed that purified hsCD83-Ig was modified by N-linked glycosylation. Moreover, the hsCD83-Ig expressed in the P. pastoris system could suppress lymphocyte proliferation in ConA-stimulated and one-way mixed lymphocyte reaction systems. Thus, hsCD83-Ig expressed in P. pastoris is functional and may be used in experimental therapies for graft rejection, graft-versus-host disease, and autoimmune diseases.

Xenograft rejection poses the largest obstacle to successful xenotransplantation. Recent studies have demonstrated that miRNAs play essential roles in embryogenesis, cell proliferation, and pathogenesis of human diseases. However, the role of miRNA in regulating xenograft rejection is relatively unknown. This study was undertaken to analyze the profile of intragraft miRNA expression in a heterotopic mouse-to-rat cardiac xenotransplantation model. Using microarray analysis, a total of 579 miRNAs were detected in the grafts following transplantation. When compared with syngeneic heart grafts, 24 and 25 miRNAs were found to differentially express in xenografts at 24 and 40 hours (endpoint of rejection), respectively, following transplantation. Three major miRNAs were then further analyzed, and it was found that the xenografts showed high expression of miR-146a and miR-155, but low expression of miR-451 when compared with isograft controls. This study suggests that miRNAs detected in this model are potentially involved in the xenogeneic immune response and could play an important role in regulating xenograft rejection. (c) 2013 Wiley Periodicals, Inc.

A brown tumor is a non-neoplasm mainly caused by hyperparathyroidism. It often occurs in the pelvis, ribs, long bone shaft, clavicle, and jaw. We introduce three cases of primary hyperparathyroidism, with the first symptom of brown tumor of the ribs, and discuss the image characteristics within the literature. We then propose the value of ultrasound in the diagnosis of brown tumor.

Stomatin-like protein 2 (SLP-2) is a mitochondrial protein of the highly conserved Stomatin, Prohibitin, Flotillin, HflC/K superfamily. The function of SLP-2 has remained unclear but members of this superfamily have been linked to membrane organization. We have previously reported that SLP-2 partitions within glycolipid-enriched, detergent-insoluble microdomains, and its expression is up-regulated upon T cell activation. This correlates with increased mitochondrial biogenesis and function. Using human inducible over-expression/down-regulation systems and newly generated T cell-specific SLP-2 knockout mice, we now report that SLP-2 binds directly and selectively to cardiolipin (CL) and interacts with prohibitins. Overexpression of SLP-2 leads to increased recruitment of prohibitins to mitochondrial membranes. This translates into optimal assembly and function of complexes I and II+III of the respiratory chain. SLP-2 deficiency in T cells is associated with abnormal CL compartmentalization and decreased respiration, which correlates with a selective post-transcriptional defect in the production of IL-2 and defective T cell (mostly CD4+) responses. Therefore, we propose that SLP-2 functions as an organizer of cardiolipin-enriched domains in mitochondrial membranes. These domains are required for optimal respiration and metabolic capacity during T cell activation. Our work also reveals a novel post-transcriptional checkpoint for IL-2 production under metabolic control.

Expression and activity of drug-metabolizing enzymes are decreased in severe kidney disease; however, only a small percentage of patients with chronic kidney disease (CKD) are at the final stage of the disease. This study aimed to determine the changes in drug-metabolizing enzyme function and expression in rats with varying degrees of kidney disease. Sprague-Dawley rats were subjected to surgical procedures that allowed the generation of three distinct models of kidney function: normal kidney function, moderate kidney function, and severe kidney disease. Forty-two days after surgery, rats were sacrificed and hepatic CYP3A and CYP2C expression was determined. In addition, enzymatic activity was determined in liver microsomes by evaluating midazolam (CYP3A), testosterone (CYP3A and CYP2C), and tolbutamide (CYP2C) enzyme kinetics. Both moderate and severe kidney disease were associated with a reduction in CYP3A2 and CYP2C11 expression (p < 0.05). Likewise, moderate kidney disease resulted in more than a 60% decrease in enzyme activity (V(max)) for CYP2C11 and CYP3A, compared with controls (p < 0.05). When the degree of kidney disease was correlated with metabolic activity, an exponential decline in CYP2C- and CYP3A-mediated metabolism was observed. Our results demonstrate that CYP3A and CYP2C expression and activity are decreased in both moderate and severe CKD. Our data suggest that drug metabolism is significantly decreased in the earlier stages of CKD and imply that patients with moderate CKD may be subject to unpredictable pharmacokinetics.

Calpain has been implicated in acute myocardial injury after myocardial infarction (MI). However, the causal relationship between calpain and post-MI myocardial remodeling has not been fully understood. This study examined whether deletion of Capn4, essential for calpain-1 and calpain-2 activities, reduces myocardial remodeling and dysfunction following MI, and if yes, whether these effects of Capn4 deletion are associated with NF-κB signaling and inflammatory responses in the MI heart. A novel mouse model with cardiomyocyte-specific deletion of Capn4 (Capn4-ko) was employed. MI was induced by left coronary artery ligation. Deficiency of Capn4 dramatically reduced the protein levels and activities of calpain-1 and calpain-2 in the Capn4-ko heart. In vivo cardiac function was relatively improved in Capn4-ko mice at 7 and 30 days after MI when compared with their wild-type littermates. Deletion of Capn4 reduced apoptosis, limited infarct expansion, prevented left ventricle dilation, and reduced mortality in Capn4-ko mice. Furthermore, cardiomyocyte cross-sectional areas and myocardial collagen deposition were significantly attenuated in Capn4-ko mice, which were accompanied by down-regulation of hypertrophic genes and profibrotic genes. These effects of Capn4 knock-out correlated with restoration of IκB protein and inhibition of NF-κB activation, leading to suppression of proinflammatory cytokine expression and inflammatory cell infiltration in the Capn4-ko heart after MI. In conclusion, deficiency of Capn4 reduces adverse myocardial remodeling and myocardial dysfunction after MI. These effects of Capn4 deletion may be mediated through prevention of IκB degradation and NF-κB activation, resulting in inhibition of inflammatory responses.

You have accessJournal of UrologyTransplantation & Vascular Surgery: Renal Transplantation, Vascular Surgery1 Apr 20112066 DONOR PRECONDITIONING WITH CORM PROTECTS THE RENAL ALLOGRAFT Patrick Luke, Alp Sener, Anthony jevnikar, Zhu Lan, Bertha Garcia, Gediminas Cepinskas, Jian Deng, and Hao Wang Patrick LukePatrick Luke London, Canada More articles by this author , Alp SenerAlp Sener London, Canada More articles by this author , Anthony jevnikarAnthony jevnikar London, Canada More articles by this author , Zhu LanZhu Lan London, Canada More articles by this author , Bertha GarciaBertha Garcia London, Canada More articles by this author , Gediminas CepinskasGediminas Cepinskas London, Canada More articles by this author , Jian DengJian Deng London, Canada More articles by this author , and Hao WangHao Wang London, Canada More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2339AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We have previously shown that carbon monoxide releasing molecules (CORM) has anti-inflammatory properties in models of ischemia reperfusion injury (IRI) and isogeneic renal transplantation. Herein, the ability of kidney donor treatment with CORM to prevent IRI in an allogeneic transplant model was assessed. METHODS Brown Norway rats were transplanted into allogeneic Lewis rats after a 6 hr cold ischemic time. Rats were untreated, treated with a low dose of tacrolimus alone (0.2 mg/kg iv), pre-treated with 8 mg/kg IP CORM 18 hr prior to procurement, or treated with a combination of tacrlimus and CORM. RESULTS Without immunotherapy, animals died within 3 days from uremia (creatinine 780±150 μmol/l) using this transplant model. In our experiment, a low dose of tacrolimus (0.2 mg/kg iv) was given to allograft recipients post-operatively. Control allografted animals did not receive CORM infusion. None of the tacrolimus-treated control animals survived beyond 12 days (Fig.1) and recipients had inferior graft function vs. CORM-treated animals at 7 days (620±50 vs. 49±6 μmol/l). Excellent graft function was noted on day 70 in CORM treated animals (creatinine 52±9 μmol/l). Accordingly, histologic examination on day 10 showed lymphocytic infiltrate, glomerular congestion, and acute tubular necrosis in controls, whereas CORM treated animals had completely normal histology on day 10. By day 70, CORM treated animals demonstrated vascular lymphocytic infiltrates, despite having excellent renal function. CONCLUSIONS These results indicate that CORM preconditioning has profound effects upon allogeneic transplantation associated with reduction of transplant-relevant inflammation and damage. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e827 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Patrick Luke London, Canada More articles by this author Alp Sener London, Canada More articles by this author Anthony jevnikar London, Canada More articles by this author Zhu Lan London, Canada More articles by this author Bertha Garcia London, Canada More articles by this author Gediminas Cepinskas London, Canada More articles by this author Jian Deng London, Canada More articles by this author Hao Wang London, Canada More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Both humoral and cellular immune responses are involved in renal allograft rejection. Interleukin (IL)-6 is a regulatory cytokine for both B and Foxp3 (forkhead box P3)-expressing regulatory T (Treg) cells. This study was designed to investigate the impact of donor IL-6 production on renal allograft survival. Donor kidneys from IL-6 knockout (KO) vs. wild-type (WT) C57BL/6 mice (H-2b) were orthotopically transplanted to nephrotomized BALB/c mice (H-2d). Alloantibodies and Treg cells were examined by fluorescence-activated cell sorting analysis. Graft survival was determined by the time to graft failure. Here, we showed that a deficiency in IL-6 expression in donor kidneys significantly prolonged renal allograft survival compared with WT controls. IL-6 protein was upregulated in renal tubules and endothelium of renal allografts following rejection, which correlated with an increase in serum IL-6 compared with that in those receiving KO grafts or naive controls. The absence of graft-producing IL-6 or lower levels of serum IL-6 in the recipients receiving IL-6 KO allografts was associated with decreased circulating anti-graft alloantibodies and increased the percentage of intragraft CD4+CD25+Foxp3+Treg cells compared with those with WT allografts. In conclusion, the lack of graft-producing IL-6 significantly prolongs renal allograft survival, which is associated with reduced alloantibody production and/or increased intragraft Treg cell population, implying that targeting donor IL-6 may effectively prevent both humoral and cellular rejection of kidney transplants.

Carbon monoxide (CO) can provide beneficial antiapoptotic and anti-inflammatory effects in the context of ischemia-reperfusion injury (IRI). Here we tested the ability of pretreating the kidney donor with carbon monoxide-releasing molecules (CORM) to prevent IRI in a transplant model. Isogeneic Brown Norway donor rats were pretreated with CORM-2 18 h before kidney retrieval. The kidneys were then cold-preserved for 26 h and transplanted into Lewis rat recipients that had undergone bilateral nephrectomy. Allografts from Brown Norway to Lewis rats were also performed after 6 h of cold ischemic time with low-dose tacrolimus treatment. All recipients receiving CORM-2-treated isografts survived the transplant process and had near-normal serum creatinine levels, whereas all control animals died of uremia by the third post-operative day. This beneficial effect was also seen in isografted Lewis recipients receiving kidneys perfused with CORM-3, indicating that CORMs have direct effects on the kidney. Pretreatment of human umbilical vein endothelial cells in culture with CORM-2 for 1 h significantly reduced cytokine-induced nicotinamide adenine dinucleotide phosphate-dependent production of superoxide, activation of the inflammation-relevant transcription factor nuclear factor-kappa B, upregulated expression of E-selectin and intercellular adhesion molecule-1 adhesion proteins, and leukocyte adhesion to the endothelial cells. Thus, CORM-2-derived CO protects renal transplants from IRI by modulating inflammation. Kidney International (2011) 79, 1080-1089; doi:10.1038/ki.2010.542; published online 26 January 2011

We have previously reported that stomatin-like protein 2 (SLP-2) regulates human T cell activation through the antigen receptor. In human lymphoid tissues, SLP-2 is widely expressed in the thymus, lymph nodes and tonsils, and its expression is further up-regulated in response to lymphocyte activation. In T cells, SLP-2 is found in two pools: the most abundant is associated with mitochondria while a smaller pool is associated with the plasma membrane. To further investigate the role of SLP-2, we generated T cell-specific SLP-2 deficient mice. These mice had normal numbers of thymocytes and mature T cells. However, SLP-2 deficient T cells showed significantly less T cell activation in response to T cell stimulation in vivo and in vitro. Although SLP-2 deficient T cells did not show significant alterations in mitochondrial biogenesis, they had decreased levels of the NDUSF3, NDUFB8 and NDUFA9 subunits of complex I of the respiratory chain, suggesting a possible role for SLP-2 in regulating the stability of proteins involved in mitochondrial electron transport. SLP-2 deficient T cells also had less cardiolipin within detergent-insoluble microdomains, which may be required for proper respiratory chain assembly and function. Based on these results, we conclude that SLP-2 contributes to T cell activation, in part by regulating stability of complex I of the respiratory chain and sustaining the metabolic requirements for T cell activation.

Background - Calpain has been implicated in myocardial injury after myocardial infarction (MI). However, no direct evidence is available on the role of calpain in post-MI myocardial remodelling and dysfunction. The present study investigated the effects of cardiomyocyte-specific deletion of Capn4 , essential for calpain-1 and calpain-2 activities on myocardial remodelling and dysfunction following MI. Methods and Results - A novel mouse model with cardiomyocyte-specific deletion of Capn4 ( Capn4-ko ) was generated. MI was induced by left coronary artery ligation. Deficiency of Capn4 significantly reduced the protein levels and activities of calpain-1 and calpain-2 in the Capn4-ko heart. In vivo cardiac function was relatively improved in Capn4-ko mice at 7 and 30 days after MI compared with their wild-type littermates. Deletion of Capn4 reduced cardiac apoptosis, limited infarct expansion and infarct zone thinning, and prevented left ventricle dilation in Capn4-ko mice. Furthermore, myocardial collagen deposition and cardiomyocyte cross-sectional areas were significantly attenuated in Capn4-ko mice, which were accompanied by down-regulation of pro-fibrotic genes and hypertrophic genes. These effects of Capn4 knockout correlated with down-regulation of inflammatory mediators and normalization of matrix metalloproteinase (MMP)-9 activity in the non-infarct area of Capn4-ko mice after MI. In vivo mouse model of endotoxemia confirmed that calpain activation resulted in inflammatory gene expression and MMP-9 activity in the heart. Conclusions - Cardiomyocyte-specific knockout of calpain attenuates myocardial adverse remodelling and improves myocardial function after MI. These beneficial effects of calpain disruption may result from inhibition of cardiac apoptosis, inflammation and MMP-9 activity.

Background. Dendritic cells (DCs) are crucial regulators of immunity and important in inducing and maintaining tolerance. Here, we investigated the potential of a novel DC-immunomodulating agent, soluble CD83 (sCD83), in inducing transplant tolerance. Methods. We used the C3H-to-C57BL/6 mouse cardiac transplantation model that exhibits a combination of severe cell-mediated rejection and moderate antibody-mediated rejection and investigated whether sCD83 could augment a combination therapy consisting of Rapamycin (Rapa) and anti-CD45RB monoclonal antibody (&agr;-CD45) to prolong allograft survival. Results. Monotherapies consisting of Rapa and &agr;-CD45 were incapable of preventing rejection. However, all treatments involving sCD83 were capable of (1) down-modulating expression of various DC surface molecules, such as major histocompatibility complex class II and costimulatory molecules, (2) reducing the allogeneic stimulatory capacity of the DCs, and (3) significantly inhibiting antidonor antibody responses. Most striking results were observed in the triple therapy-treated group, sCD83+Rapa+&agr;-CD45, where cell-mediated rejection and antibody-mediated rejection were abrogated for over 100 days. Donor-specific tolerance was achieved in long-term surviving recipients, because donor skin transplants were readily accepted for an additional 100 days, whereas third-party skin grafts were rejected. Success of triple therapy treatment was accompanied by enhancement of tolerogenic-DCs that conferred antigen-specific protection on adoptive transfer to recipients of an allogeneic heart graft. Conclusions. Our study revealed that sCD83 is capable of attenuating DC maturation and function, and inducing donor-specific allograft tolerance, in the absence of toxicity. Thus, sCD83 seems to be a safe and valuable counterpart to current DC-modulating agents.

You have accessJournal of UrologyTransplantation & Vascular Surgery: Renal Transplantation, Vascular Surgery II1 Apr 20102171 RENAL TRANSPLANT PROTECTION USING PERFUSATE-BASED CARBON MONOXIDE RELEASING MOLECULES Patrick Luke, Jian Deng, Hao Wang, Hong Tao Sun, Anthony Jevnikar, and Gediminas Cepinskas Patrick LukePatrick Luke More articles by this author , Jian DengJian Deng More articles by this author , Hao WangHao Wang More articles by this author , Hong Tao SunHong Tao Sun More articles by this author , Anthony JevnikarAnthony Jevnikar More articles by this author , and Gediminas CepinskasGediminas Cepinskas More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.2274AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Carbon monoxide (CO) has previously been shown to reduce damage associated with ischemia reperfusion injury, but is difficult to store and deliver CO in a safe, controlled manner. Therefore, we assessed the ability of novel carbon monoxide releasing molecules (CORM) to prevent graft injury as well as endothelial and epithelial apoptosis. METHODS To assess the ability of CORM-3 to protect human tubular epithelial cell (TEC) and human umbilical vein endothelial cell (HUVEC) from cytokine-mediated injury, TEC were incubated in 10 ng/ml TNF-a and IFN-g for 24 hr. As well, cells were incubated in an anoxia/reoxygenation chamber. In parallel, isogeneic Lewis to Lewis renal transplants were performed with a 26 hr cold ischemic time. Group 1 animals had 100 microM CORM-3 infusion into the graft at the time of retrieval and prior to implantation along with 26 hr cold storage in University of Wisconsin solution (UW) (n = 6). Group 2 animals (n = 6) were stored for 26 hr in cold UW solution. RESULTS Using Annexin V/ 7-AAD staining, cell death was shown to be reduced in both TEC and HUVEC after pre-incubation in CORM-3 in a concentration-dependent manner with optimal protection at 100 microM of CORM-3. Pre-incubation in inactivated CORM (iCORM-3) failed to offer protection. Five of 6 recipients that received CORM-3 isografts survived the transplant process, whereas all control animals died by day 3 post-operatively. The mean serum creatinine (sCr) in Groups 1 and 2 were 191+/- 224 and 680+/-15 umol/L by 72 hr, respectively (p<0.05). Early post-operative histology revealed that CORM-3-treated grafts suffered mild acute tubular necrosis whereas controls experienced severe injury. CONCLUSIONS In summary, we have shown that perfusate-infused CORM-3 protects the renal transplant and prevents apoptosis of relevant epithelial and endothelial cells from anoxia/reoxygenation and inflammation-related injury. This provides rationale to use CORM in transplant perfusate solutions to protect the organ during cold storage and reperfusion. London, Canada© 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e845 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Patrick Luke More articles by this author Jian Deng More articles by this author Hao Wang More articles by this author Hong Tao Sun More articles by this author Anthony Jevnikar More articles by this author Gediminas Cepinskas More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Background. The immunoregulatory properties of mesenchymal stem cells (MSCs) have been observed in vitro and in vivo. However, the underlying mechanisms of this immunomodulation remain undefined. Recent research demonstrated that MSCs express the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO), known to suppress T-cell responses. This study was designed to address whether MSCs induce kidney allograft tolerance and whether IDO contributes to the immunoregulatory functions of MSCs in vivo. Methods. MSCs (1×106, intravenously) from wild-type (WT-MSCs) or IDO knockout (IDO−/−-MSCs) C57BL/6 mice were injected into BALB/c recipients 24 hr after receiving a life-supporting orthotopic C57BL/6 renal graft. Results. WT-MSC-treated recipients achieved allograft tolerance with normal histology and undetectable antidonor antibody levels. Tolerant recipients demonstrated increased circulating kynurenine levels and significantly high frequencies of tolerogenic dendritic cells. They also exhibited significantly impaired CD4+ T-cell responses consisting of decreased donor-specific proliferative ability and a Th2-dominant cytokine shift. In addition, high frequencies of CD4+CD25+Foxp3+ regulatory T cells (Tregs) were found in recipient spleens and donor grafts, with antibody-induced CD25+ cell depletion confirming the critical role of Tregs in the MSC-induced tolerance. Interestingly, renal allograft recipients treated with WT MSCs concomitant with the IDO inhibitor 1-methyl-tryptophan, or those treated with IDO−/−-MSCs alone, were unable to achieve allograft tolerance—revealing that functional IDO was necessary for the immunosuppression observed with WT-MSC treatment. Conclusions. IDO secreted by MSCs was responsible, at least in part, for induction of kidney allograft tolerance through generation of Tregs. This study supports the clinical application of MSCs in transplantation.