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1.
Animals (Basel) ; 14(7)2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38612332

ABSTRACT

Sinus venosus atrial septal defects (SVASDs), concurrent with partial anomalous pulmonary venous connections (PAPVCs), are a rare congenital heart disease in dogs. Surgical correction is essential when clinical signs or significant hemodynamic changes are present. We aimed to report on the successful surgical correction of an SVASD with PAPVCs, using a computed tomography (CT)-based customized 3D cardiac model. A 10-month-old male poodle was referred for corrective surgery for an ASD. Echocardiography confirmed a hemodynamically significant left-to-right shunting flow through an interatrial septal defect and severe right-sided heart volume overload. For a comprehensive diagnosis, a CT scan was performed, which confirmed an SVASD with PAPVCs. A customized 3D cardiac model was used for preoperative decision-making and surgical rehearsal. The defect was repaired using an autologous pericardial patch under a cardiopulmonary bypass (CPB). Temporary pacing was applied for sinus bradycardia and third-degree atrioventricular block. The patient recovered from the anesthesia without further complications. The pacemaker was removed during hospitalization and the patient was discharged without complications 2 weeks post-surgery. At the three-month follow-up, there was no shunting flow in the interatrial septum and the right-sided volume overload had been resolved. The cardiac medications were discontinued, and there were no complications. This report indicates the validity of surgical correction under CPB for an SVASD with PAPVCs, and the advantages of utilizing a CT-based 3D cardiac model for preoperative planning to increase the surgical success rate.

2.
J Vet Sci ; 24(3): e47, 2023 May.
Article in English | MEDLINE | ID: mdl-37271514

ABSTRACT

Del-Nido cardioplegia (DNc) is a single-dose cardioplegia that is widely used in human medicine because of its long duration. In this report, we describe two cases of open-heart surgery with cardiopulmonary bypass (CPB) using DNc. One dog was diagnosed with partial atrioventricular septal defect, and the other dog was diagnosed with myxomatous mitral valve disease stage D. Both dogs were treated with open-heart surgery with DNc to induce temporary cardiac arrest. No complications from DNc were observed, and the patients were discharged. Veterinary heart surgeons should consider DNc as an option for temporary cardiac arrest during open-heart surgery with CPB.


Subject(s)
Cardiac Surgical Procedures , Dog Diseases , Heart Arrest , Humans , Dogs , Animals , Cardioplegic Solutions , Heart Arrest, Induced/veterinary , Cardiac Surgical Procedures/veterinary , Heart Arrest/veterinary , Retrospective Studies , Dog Diseases/surgery
3.
Diabetes ; 68(4): 837-846, 2019 04.
Article in English | MEDLINE | ID: mdl-30679183

ABSTRACT

Mesenchymal stem cells (MSCs) may hold great promise for treating diabetic wounds. However, it is difficult for a clinician to use MSCs because they have not been commercialized. Meanwhile, a new commercial drug that contains adipose-derived stem cells (ASCs) has been developed. The purpose of this study was to examine the potential of allogeneic ASC sheets for treating diabetic foot ulcers. Fifty-nine patients with diabetic foot ulcers were randomized to either the ASC treatment group (n = 30) or a control group treated with polyurethane film (n = 29). Either an allogeneic ASC sheet or polyurethane film was applied on diabetic wounds weekly. These wounds were evaluated for a maximum of 12 weeks. Complete wound closure was achieved for 73% in the treatment group and 47% in the control group at week 8. Complete wound closure was achieved for 82% in the treatment group and 53% in the control group at week 12. The Kaplan-Meier median times to complete closure were 28.5 and 63.0 days for the treatment group and the control group, respectively. There were no serious adverse events related to allogeneic ASC treatment. Thus, allogeneic ASCs might be effective and safe to treat diabetic foot ulcers.


Subject(s)
Adipocytes/cytology , Diabetic Foot/therapy , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Stem Cell Transplantation/adverse effects , Wound Healing/physiology , Young Adult
4.
Stem Cells Transl Med ; 4(5): 532-7, 2015 May.
Article in English | MEDLINE | ID: mdl-25829404

ABSTRACT

A previous phase II clinical trial of adipose-derived stem cell (ASC) therapy for fistulae associated with Crohn's disease, a devastating condition with a high recurrence rate, demonstrated safety and therapeutic potential with a 1-year sustained response. In the present study, 41 of the 43 phase II trial patients were followed for an additional year, regardless of response in the initial year. At 24 months, complete healing was observed in 21 of 26 patients (80.8%) in modified per protocol analysis and 27 of 36 patients (75.0%) in modified intention-to-treat analysis. No adverse events related to ASC administration were observed. Furthermore, complete closure after initial treatment was well-sustained. These results strongly suggest that autologous ASCs may be a novel treatment option for Crohn's fistulae.


Subject(s)
Cell- and Tissue-Based Therapy , Crohn Disease/therapy , Fistula/therapy , Mesenchymal Stem Cell Transplantation , Adolescent , Adult , Crohn Disease/pathology , Female , Fistula/pathology , Humans , Male , Middle Aged , Transplantation, Autologous , Treatment Outcome , Wound Healing
5.
Stem Cells Transl Med ; 3(11): 1312-21, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25273542

ABSTRACT

We recently reported that autologous adipogenic differentiated adipose-derived stem cells (ASCs) can potentially be used as an effective and safe therapy for soft-tissue regeneration. In the present study, we investigated whether adipogenic differentiated ASCs can be used for allogenic applications to enlarge their therapeutic use. The allogenic immune response of adipogenic differentiated ASCs was investigated by flow cytometry and mixed lymphocyte culture. To determine whether adipogenic differentiated ASCs can form new adipose tissue without immune rejection, these cells were implanted subcutaneously into allo- or xenogenic recipient mice. In addition, the safety of the allogenic implantation of adipogenic differentiated ASCs was explored in a phase I clinical study. Adipogenic differentiated ASCs do not express major histocompatibility complex (MHC) class II molecules and costimulatory molecules, and the expression levels of MHC class I decreased after differentiation. In addition, these cells do not elicit an immune response against MHC-mismatched allogenic lymphocytes and formed new adipose tissue without immune rejection in the subcutaneous region of MHC-mismatched mice. Moreover, these cells did not induce clinically significant local and systemic immune responses or adverse events in the subcutaneous region of donor-independent healthy subjects. These results suggest that adipogenic differentiated ASCs can be used as a "universal donor" for soft-tissue engineering in MHC-mismatched recipients.


Subject(s)
Adipogenesis , Adipose Tissue , Cell Differentiation , Stem Cell Transplantation , Stem Cells , Adipose Tissue/cytology , Adipose Tissue/metabolism , Allografts , Animals , Heterografts , Humans , Male , Mice , Mice, Inbred BALB C , Stem Cells/cytology , Stem Cells/metabolism
6.
Tissue Eng Part A ; 19(21-22): 2373-81, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23701237

ABSTRACT

Fibrin glue has been widely investigated as a cell delivery vehicle for improving the therapeutic effects of mesenchymal stem cells (MSCs). Implanted MSCs produce their therapeutic effects by secreting paracrine factors and by replacing damaged tissues after differentiation. While the influence of fibrin glue on the differentiation potential of MSCs has been well documented, its effect on paracrine function of MSCs is largely unknown. Herein we investigated the influence of fibrin glue on the paracrine effects of MSCs. MSCs were isolated from human adipose tissue. The effects of fibrin glue on survival, migration, secretion of growth factors, and immune suppression of MSCs were investigated in vitro. MSCs in fibrin glue survived and secreted growth factors such as the vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) over 14 days. VEGF and immune modulators, including the transforming growth factor (TGF)-ß1 and prostaglandin E2, secreted from MSCs in fibrin glue significantly increased under inflammatory conditions. Thus, MSCs in fibrin glue effectively suppressed immune reactions. In addition, fibrin glue protected the MSCs from oxidative stress and prevented human dermal fibroblast death induced by exposure to extreme stress. In contrast, MSCs within fibrin glue hardly migrated. These results suggest that fibrin glue may sustain survival of implanted MSCs and their paracrine function. Our results provide a mechanistic data to allow further development of MSCs with fibrin glue as a clinical treatment.


Subject(s)
Fibrin Tissue Adhesive/pharmacology , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Cell Differentiation/drug effects , Cell Survival/drug effects , Cells, Cultured , Humans , Mesenchymal Stem Cells/metabolism
7.
Stem Cells ; 31(11): 2575-81, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23404825

ABSTRACT

Fistula is a representative devastating complication in Crohn's patients due to refractory to conventional therapy and high recurrence. In our phase I clinical trial, adipose tissue-derived stem cells (ASCs) demonstrated their safety and therapeutic potential for healing fistulae associated with Crohn's disease. This study was carried out to evaluate the efficacy and safety of ASCs in patients with Crohn's fistulae. In this phase II study, forty-three patients were treated with ASCs. The amount of ASCs was proportioned to fistula size and fistula tract was filled with ASCs in combination with fibrin glue after intralesional injection of ASCs. Patients without complete closure of fistula at 8 weeks received a second injection of ASCs containing 1.5 times more cells than the first injection. Fistula healing at week 8 after final dose injection and its sustainability for 1-year were evaluated. Healing was defined as a complete closure of external opening without any sign of drainage and inflammation. A modified per-protocol analysis showed that complete fistula healing was observed in 27/33 patients (82%) by 8 weeks after ASC injection. Of 27 patients with fistula healing, 26 patients completed additional observation study for 1-year and 23 patients (88%) sustained complete closure. There were no adverse events related to ASC administration. ASC treatment for patients with Crohn's fistulae was well tolerated, with a favorable therapeutic outcome. Furthermore, complete closure was well sustained. These results strongly suggest that autologous ASC could be a novel treatment option for the Crohn's fistula with high-risk of recurrence.


Subject(s)
Adipose Tissue/transplantation , Crohn Disease/surgery , Fistula/surgery , Rectal Fistula/surgery , Stem Cell Transplantation/methods , Adipose Tissue/cytology , Adult , Cell Growth Processes/physiology , Crohn Disease/complications , Female , Humans , Male , Rectal Fistula/etiology , Transplantation, Autologous , Treatment Outcome
8.
Cell Transplant ; 22(2): 279-85, 2013.
Article in English | MEDLINE | ID: mdl-23006344

ABSTRACT

The present study was designed to evaluate the safety and potential of adipose tissue-derived stem cells (ASCs) for the treatment of Crohn's fistula. In this dose escalation study, patients were sequentially enrolled into three dosing groups with at least three patients per group. The first three patients (group 1) were given 1 × 10(7) cells/ml. After 4 weeks, this dose was deemed safe, and so an additional four patients (group 2) were given 2 × 10(7) cells/ml. Four weeks later, after which this second dose was deemed safe, a third and final group of three patients were given 4 × 10(7) cells/ml. Each patient was followed for a minimum of 8 weeks. Patients who showed complete healing at week 8 were followed up for an additional 6 months. Efficacy endpoint was complete healing at week 8 after injection, defined as complete closure of the fistula track and internal and external openings without drainage or signs of inflammation. There were no grade 3 or 4 severity adverse events, and there were no adverse events related to the study drug. Two patients in group 2, treated with 2 × 10(7) ASCs/ml, showed complete healing at week 8 after injection. Of the three patients enrolled in group 3, treated with 4 × 10(7) ASCs/ml, one showed complete healing. Outcome in another patient was assessed as partial healing due to incomplete closure of the external opening, although the inside of fistula track was filled considerably and there was no drainage. All three patients with complete healing at week 8 showed a sustained effect without recurrence 8 months after injection. In conclusion, this study demonstrates the tolerability, safety, and potential efficacy of ASCs for the treatment of Crohn's fistula and provides support for further clinical study.


Subject(s)
Adipose Tissue/transplantation , Crohn Disease/surgery , Mesenchymal Stem Cell Transplantation/methods , Rectal Fistula/surgery , Adipose Tissue/cytology , Adult , Crohn Disease/drug therapy , Female , Humans , Male , Rectal Fistula/drug therapy , Treatment Outcome
9.
Acta Biomater ; 8(9): 3524-31, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22583904

ABSTRACT

Wear particles liberated from the surfaces of an implanted prosthesis are associated with peri-implant osteolysis and subsequent aseptic loosening. In the latter wear particle-induced inflammation and osteoclastogenesis have been identified as critical factors, and their inhibition as important steps in the treatment of affected patients, such as those undergoing total hip replacement. In this study the ability of luteolin to inhibit both titanium (Ti) particle-induced osteoclastogenesis in vitro and osteolysis in a murine calvaria Ti particle-induced model of osteolysis was examined. The results showed that luteolin, a highly potent and efficient inhibitor of tumor necrosis factor α (TNF-α) and interleukin-6 expression, inhibited Ti particle-induced inflammatory cytokine release, osteoclastogenesis, and bone resorption in bone marrow macrophages. Microcomputed tomography and histological analyses showed that the Ti particles caused significant bone resorption and increased TRAP(+) multinuclear osteoclasts in the murine calvarial model of osteolysis, whereas this was not the case in the luteolin treatment group, in which osteolytic suppression was accompanied by a decrease in both TNF-α production and serum levels of the osteoclast marker the C-terminal telopeptide fragment of type I collagen. These results support the use of luteolin as a natural compound in the prevention and treatment of aseptic loosening after total replacement arthroplasty.


Subject(s)
Luteolin/pharmacology , Osteolysis/chemically induced , Titanium/adverse effects , Animals , Base Sequence , Cell Differentiation , Culture Media, Conditioned , DNA Primers , Disease Models, Animal , Male , Mice , Mice, Inbred ICR , Osteoclasts/cytology , Osteoclasts/drug effects , Prostheses and Implants , Reverse Transcriptase Polymerase Chain Reaction
10.
Waste Manag ; 31(9-10): 2112-20, 2011.
Article in English | MEDLINE | ID: mdl-21612904

ABSTRACT

The costs associated with eight food waste disposal options, dry feeding, wet feeding, composting, anaerobic digestion, co-digestion with sewage sludge, food waste disposer, incineration, and landfilling, were evaluated in the perspective of global warming and energy and/or resource recovery. An expanded system boundary was employed to compare by-products. Life cycle cost was analyzed through the entire disposal process, which included discharge, separate collection, transportation, treatment, and final disposal stages, all of which were included in the system boundary. Costs and benefits were estimated by an avoided impact. Environmental benefits of each system per 1 tonne of food waste management were estimated using carbon prices resulting from CO(2) reduction by avoided impact, as well as the prices of by-products such as animal feed, compost, and electricity. We found that the cost of landfilling was the lowest, followed by co-digestion. The benefits of wet feeding systems were the highest and landfilling the lowest.


Subject(s)
Garbage , Global Warming , Models, Economic , Republic of Korea
11.
Dermatol Surg ; 37(6): 750-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21575095

ABSTRACT

BACKGROUND: Adipose tissue-derived stem cells (ASCs) are considered to be a reliable cell source for the generation of adipose tissue because they can be differentiated into adipocytes. Previous data have indicated that adipogenic differentiation of ASCs before transplantation can enhance the regeneration of adipose tissue. OBJECTIVE: To evaluate the efficacy and safety of the use of autologous differentiated adipocytes for the treatment of depressed scars. METHODS: Autologous differentiated adipocytes were produced using well-established techniques, including the harvesting of stromal vascular fraction cells from lipoaspirates, expansion of ASCs, and differentiation into adipocytes. This was an open-label, dose-escalation study. Patients were given a subcutaneous injection of differentiated adipocytes and followed for 12 weeks. RESULTS: Thirty-one patients were injected with differentiated adipocytes. When the differentiated adipocytes were injected subcutaneously into depressed scars, the average recovery in volume was 74.6% at 12 weeks. Of 17 patients who completed the follow-up after determination of dose, seven were willing to enroll for extended follow-up. Long-term follow-up revealed that the recovery in volume at 12 weeks was maintained well for at least 1 year. There were no significant adverse events. CONCLUSIONS: The use of autologous differentiated adipocytes can be a safe and effective treatment for soft tissue defects, with relatively long-term maintenance of volume. The authors have indicated no significant interest with commercial supporters.


Subject(s)
Adipocytes/transplantation , Cicatrix/therapy , Stem Cell Transplantation , Adult , Cell Differentiation/genetics , Female , Gene Expression/genetics , Humans , Male , Statistics, Nonparametric , Stem Cell Transplantation/adverse effects , Stem Cells , Treatment Outcome
12.
Dermatol Surg ; 36(7): 1078-83, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20653721

ABSTRACT

BACKGROUND: Although frozen adipose tissue is frequently used for soft tissue augmentation, the viability of frozen fat remains a controversy. The cryopreservation of adipose tissue is important for the future use of adipose-derived stem cells (ASCs) and adipocytes. OBJECTIVE: To determine whether optimal cryopreservation techniques with regard to the addition of cryopreservative agents and preservation temperature is essential for the long-term storage of adipose tissue and whether ASCs from cryopreserved adipose aspirates are reliable for use in adipogenic differentiation. MATERIALS AND METHODS: Adipose tissue was frozen directly or with cryoprotectant at -20 degrees C or -80 degrees C for 1 year. The viability of adipose aspirates and the differentiation of ASCs isolated from adipose tissue were evaluated. RESULTS: The viability of adipose aspirates frozen with dimethyl sulfoxide at -80 degrees C was approximately 87% after 2 months of storage. Moreover, ASCs from adipose tissue stored with cryoprotectant survived successfully for 1 year and differentiated into adipocytes, although ASCs were not detected in the directly frozen adipose tissue. CONCLUSION: Adipose tissue cryopreserved with cryoprotectant and stored at optimal temperature might prove to be a reliable source of human ASCs and adipocytes.


Subject(s)
Adipocytes/cytology , Adipogenesis/physiology , Adult Stem Cells/cytology , Cryopreservation/methods , Subcutaneous Fat/cytology , Cryoprotective Agents , Dimethyl Sulfoxide , Freezing , Humans , Lipectomy , Tissue Culture Techniques , Tissue Survival
13.
Sci Total Environ ; 408(19): 3998-4006, 2010 Sep 01.
Article in English | MEDLINE | ID: mdl-20580812

ABSTRACT

This study evaluated feed manufacturing including dry feeding and wet feeding, composting, and landfilling for food waste disposal options from the perspective of global warming and resource recovery. The method of the expanded system boundaries was employed in order to compare different by-products. The whole stages of disposal involved in the systems such as separate discharge, collection, transportation, treatment, and final disposal, were included in the system boundary and evaluated. The Global Warming Potential generated from 1tonne of food wastes for each disposal system was analyzed by the life cycle assessment method. The results showed that 200kg of CO(2)-eq could be produced from dry feeding process, 61kg of CO(2)-eq from wet feeding process, 123kg of CO(2)-eq from composting process, and 1010kg of CO(2)-eq from landfilling. Feed manufacturing and composting, the common treatment methods currently employed, have been known to be environment friendlier than other methods. However, this study shows that they can negatively affect the environment if their by-products are not appropriately utilized as intended.


Subject(s)
Conservation of Natural Resources , Garbage , Global Warming , Waste Management/methods , Air Pollutants/analysis , Carbon Dioxide/analysis , Methane/analysis
14.
J Am Coll Cardiol ; 51(9): 933-43, 2008 Mar 04.
Article in English | MEDLINE | ID: mdl-18308163

ABSTRACT

OBJECTIVES: The goal of this study was to investigate the effect of pre-treatment of mesenchymal stem cells (MSCs) with growth factors (GFs) on cardiomyogenic differentiation, cytoprotective action on cardiomyocytes (CMCs), and their therapeutic efficacy in myocardial infarction. BACKGROUND: Mechanisms of myocardial repair with MSC transplantation have not been fully elucidated, and therapeutic efficacy needs to be enhanced. METHODS: The MSCs obtained from the bone marrow of Fisher344 rats were treated with fibroblast growth factor-2, insulin-like growth factor-1, and bone morphogenetic protein-2. The expression of cardiac specific markers and the cytoprotective effect of MSCs with its mechanism were evaluated. Efficacy of MSCs transplantation was studied in rat myocardial infarction model. RESULTS: Treatment of MSCs with cocktails of GFs enhanced expression of cardiac transcription factors and survival. Induction of cardiac specific markers by coculture with CMCs and gap junctional communication with CMCs was more active in GF-treated MSCs than untreated MSCs. The GF-treated MSCs reduced apoptosis of neighboring CMCs in a hypoxic condition and enhanced the phosphorylated Akt and phosphorylated c-AMP response element binding protein expression of CMCs, which was markedly reduced by gap junction blockade. In a rat myocardial infarction model, transplantation of GF-treated MSCs resulted in smaller infarct size and better cardiac function than transplantation of untreated MSCs. Additionally, GF treatment enhanced gap junction formation of transplanted MSCs, which did not aggravate arrhythmia. CONCLUSIONS: Pre-treatment of MSCs with GFs enhanced cytoprotective effects on neighboring CMCs through gap junction and improved the therapeutic efficacy of MSC transplantation for myocardial repair. "Priming of MSCs with GFs" before transplantation might improve the therapeutic efficacy of cell therapy.


Subject(s)
Bone Morphogenetic Proteins/pharmacology , Fibroblast Growth Factor 2/pharmacology , Gap Junctions/drug effects , Insulin-Like Growth Factor I/pharmacology , Mesenchymal Stem Cells/drug effects , Myocardial Infarction/therapy , Myocytes, Cardiac/drug effects , Transforming Growth Factor beta/pharmacology , Animals , Bone Morphogenetic Protein 2 , Cell Differentiation/drug effects , Disease Models, Animal , Gap Junctions/metabolism , Gene Expression , Male , Mesenchymal Stem Cell Transplantation , Myocytes, Cardiac/metabolism , Rats , Rats, Inbred F344
15.
Nephrol Dial Transplant ; 23(1): 126-35, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17704110

ABSTRACT

BACKGROUND: TGF-beta is involved in peritoneal changes during long-term peritoneal dialysis (PD). TGF-beta induces betaig-h3 in several cell lines, and betaig-h3 may be a marker for biologically active TGF-beta. However, no study has reported induction of betaig-h3 in human peritoneal mesothelial cells (HPMCs) or its involvement in PD-related peritoneal membrane changes. METHODS: We used cultured HPMCs to investigate the biological roles of betaig-h3 during mesothelial cell injury and repair, employing the adhesion, spreading, scratching and cell migration assays. Changes in betaig-h3 expression after high glucose exposure in vivo were also evaluated using an animal chronic PD model. RESULTS: In vitro, TGF-beta1 induced betaig-h3 in cultured HPMCs, and betaig-h3-mediated mesothelial cell adhesion occurred via alphavbeta3 integrin. betaig-h3 enhanced mesothelial cell adhesion and migration and, in part, wound healing during mesothelial cell injury. The animal study demonstrated that compared to the control group, betaig-h3 concentrations in the dialysate effluent increased in the dialysis group with alterations in peritoneal structure and function during PD, and betaig-h3 positively correlated with peritoneal solute transport. Immunohistochemical and immunoblotting results showed that betaig-h3 localizes in the mesothelium and submesothelial matrix of the parietal peritoneum, and in the vascular endothelium of omentum. betaig-h3 protein expression was higher in the dialysis group. CONCLUSION: In vitro, betaig-h3 induced by TGF-beta1 in HPMCs improved adhesion and migration of HPMCs during wound healing. In the chronic infusion model of PD, betaig-h3 played a role in the functional deterioration of the peritoneal membrane, which is associated with fibrosis.


Subject(s)
Extracellular Matrix Proteins/physiology , Peritoneal Dialysis , Transforming Growth Factor beta/physiology , Cells, Cultured , Epithelial Cells/metabolism , Extracellular Matrix Proteins/biosynthesis , Humans , Peritoneum/cytology , Peritoneum/metabolism , Transforming Growth Factor beta/biosynthesis
16.
Ther Apher Dial ; 11(1): 56-64, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17309576

ABSTRACT

In the present study, we examined the effects of a new peritoneal dialysis fluid (PDF) with a low level of low glucose degradation products (GDP) on the functional and structural stability of the peritoneal membrane (PM). Male Sprague-Dawley rats were divided into three groups: group C (n = 8), without dialysate infusion; group P (n = 12), infused with low-level GDP solution (4.25% Physioneal, pH 7.0-7.4); and group D (n = 12), infused with conventional solution (4.25% Dianeal, pH 5.2, adjusted to pH 7.0). In groups D and P, animals were infused through a permanent catheter with 25 mL of PDF, twice daily for 8 weeks. Lipopolysaccharide was added into the PDF immediately before infusion on days 8, 9 and 10 in the two dialysis groups. When compared with group P, group D showed a higher glucose mass transfer at weeks 6 and 8, D/P urea at week 8, TGF-beta1 at weeks 4 and 8, and VEGF level at week 8. The submesothelial matrix layer of the parietal peritoneum was significantly thickened in group D and the lectin-stained blood vessels in this layer were well-visualized in group D compared with group P. There were significantly more peritoneal blood vessels in group D than group P. The transforming growth factor-beta induced gene-h3 (betaig-h3) and TGF-beta1 levels in the peritoneal effluent correlated with the submesothelial thickness, which correlated with the dialysate-to-plasma ratio (D/P) of protein and, inversely, with the rate of glucose transport (D/D(0) glucose, where D is glucose concentration in the dialysate and D(0) is glucose concentration in the dialysis solution before it is infused into the peritoneal cavity). The present study showed that low-GDP PDF effectively attenuated the peritoneal vascularization and fibrosis related to conventional solution.


Subject(s)
Dialysis Solutions/pharmacology , Glucose/pharmacology , Peritoneal Dialysis , Peritoneum/drug effects , Animals , Blotting, Western , Extracellular Matrix Proteins/metabolism , Fibrosis , Immunohistochemistry , Male , Peritoneum/blood supply , Peritoneum/metabolism , Peritoneum/pathology , Rats , Rats, Sprague-Dawley , Transforming Growth Factor beta/metabolism , Transforming Growth Factor beta1/metabolism
17.
Int Immunol ; 18(3): 435-44, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16431877

ABSTRACT

Although it is well established that antigen dose plays an important role in determining the quality of T cells induced in vitro, it has not well been determined whether antigen dose also affects T cell repertoires induced in vivo. This study demonstrates that variation of antigen doses in vivo as well as in vitro induce structurally and functionally different T cell repertoires. CTLs generated in vitro with a low antigen dose showed much higher T cell responsiveness than CTLs generated with a high antigen dose, and the two CTL populations employed different TCR Vbeta chains. This is most likely due to repertoire selection based on TCR affinity. The secondary in vivo responses with a high or low dose of antigen following the primary response raised with the same dose resulted in a reversed dominance pattern of two particular TCR Vbeta phenotypes. TCR affinity of these two T cell populations appeared different, suggesting avidity selection based on antigen availability. Indeed, they required a distinct level of antigen for maximal cytolytic function, implying a different functional avidity. These results suggest that antigen-specific T cell repertoire is substantially affected by the antigen dose employed in vivo as well as in vitro.


Subject(s)
Antigens/immunology , T-Lymphocytes, Cytotoxic/immunology , Adenovirus E1B Proteins/administration & dosage , Adenovirus E1B Proteins/immunology , Animals , Antigens/administration & dosage , Clone Cells/immunology , Dose-Response Relationship, Immunologic , Female , Male , Mice , Receptors, Antigen, T-Cell/immunology
18.
J Biochem Mol Biol ; 38(3): 334-42, 2005 May 31.
Article in English | MEDLINE | ID: mdl-15943910

ABSTRACT

Recently, the existence of T cells with dual T cell receptor (TCR) in the immune system is generally accepted, while it has been controversial whether signals through one TCR would affect the functions of the other. In this study T cells expressing two different TCR were obtained from cross-hybrids of LCMV and AND TCR transgenic mice specific for the gp33 and peptide fragment of PCC (fPCC), respectively. Peptide stimulation demonstrated that the dual TCR T cells functioned independently in an antigen-specific manner. To examine whether the tolerance targeted for the one TCR affects the responsiveness of the other, the cross-hybrids were treated with gp33. Although T cells from F1 mice were rendered anergenic to gp33, no functional changes to fPCC were observed in terms of cellular proliferation and IL-2 secretion, suggesting that the dual TCR T cells remained reactive to fPCC. We therefore propose that signaling through the TCR is receptor-specific and 'negative dominance' of one TCR by tolerance induction is not applicable in this dual TCR system.


Subject(s)
Receptors, Antigen, T-Cell/immunology , T-Lymphocytes/microbiology , Animals , CD8-Positive T-Lymphocytes/immunology , Cell Culture Techniques , Crosses, Genetic , Cytotoxicity, Immunologic , Humans , Immune Tolerance , Interleukin-2/analysis , Lymphocyte Activation , Mice , Mice, Inbred C57BL , Mice, Inbred Strains , Mice, Transgenic , Signal Transduction/immunology
19.
Biochem Biophys Res Commun ; 296(2): 434-42, 2002 Aug 16.
Article in English | MEDLINE | ID: mdl-12163038

ABSTRACT

The Src homology 3 (SH3) domain plays a crucial role in protein-protein interactions during intracellular signal transduction. Blocking the SH3-mediated protein binding may inhibit the corresponding signal transduction, and thus, block the cellular functions. In this study, a peptide that specifically binds to SH3 domain could be introduced into the intracellular region when the peptides were conjugated with dipalmitic acid and appeared to disturb intracellular signaling. The dipalmitoyl peptide appeared to inhibit the phosphorylation of ZAP-70, Lck, and T-cell antigen receptor zeta in Jurkat. Mobilization of the intracellular free calcium induced by anti-CD3 antibody was reduced after treatment with the dipalmitoyl peptide. It was also observed that the dipalmitoyl peptide inhibited cancer cell growth both in vitro and in vivo. These results suggest that the dipalmitoyl peptide that presumably disturbs SH3-mediated signal transduction may have a potent anti-proliferative activity, which would be useful as a potential anti-tumor agent.


Subject(s)
Palmitic Acids/metabolism , Peptides/metabolism , Signal Transduction/physiology , src Homology Domains/genetics , Animals , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/metabolism , Calcium/metabolism , Cell Division/drug effects , Energy Transfer , Flow Cytometry , Fluorescent Dyes/metabolism , Humans , Jurkat Cells , Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/metabolism , Membrane Proteins/metabolism , Mice , Mice, Nude , Neoplasm Transplantation , Palmitic Acids/pharmacology , Peptides/chemical synthesis , Peptides/pharmacology , Protein-Tyrosine Kinases/metabolism , Receptors, Antigen, T-Cell/metabolism , Recombinant Fusion Proteins/metabolism , Tumor Cells, Cultured , ZAP-70 Protein-Tyrosine Kinase
20.
Virology ; 295(2): 238-49, 2002 Apr 10.
Article in English | MEDLINE | ID: mdl-12033782

ABSTRACT

This study describes the characteristics of the immune responses against adenovirus in C57BL/6 mice. CTL responses could be induced against E1Bp of adenovirus type 5, when whole viruses were immunized. A panel of E1Bp-specific CTL clones showed a wide range of T cell avidity. Recognition of the E1Bp peptide and a panel of variant peptides containing a single alanine substitution by CTL clones revealed that the fine specificity of the CTL response was quite diverse, rather than being limited to a certain clonal preference. Moreover, the variant peptides with a substitution at the TCR contact residue had antagonistic properties to some of the CTL clones, while being agonistic to others, reflecting the extensive diversity of the T cells. These results imply that the functional diversity of T cells to even a single epitope should be considered in manipulating immunity to viruses and in developing adoptive immunotherapy for immunocompromised individuals.


Subject(s)
Adenovirus E1B Proteins/immunology , Adenoviruses, Human/immunology , CD8-Positive T-Lymphocytes/immunology , Epitopes, T-Lymphocyte/immunology , Receptors, Antigen, T-Cell, alpha-beta/metabolism , Adenovirus E1B Proteins/chemistry , Adenoviruses, Human/genetics , Animals , Clone Cells , Cytotoxicity Tests, Immunologic , Female , Humans , Interferon-gamma/biosynthesis , Male , Mice , Mice, Inbred C57BL , Receptors, Antigen, T-Cell, alpha-beta/genetics , Vaccination , Viral Vaccines/immunology
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