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1.
Stem Cell Res Ther ; 13(1): 350, 2022 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-35883190

RESUMEN

BACKGROUND: The purpose of this study was to investigate allogenic immune responses following the transplantation of insulin-producing cells (IPCs) differentiated from human adipose tissue-derived stem cells (hAT-MSCs) into humanized mice. METHODS: hAT-MSCs were isolated from liposuction aspirates obtained from HLA-A2-negative healthy donors. These cells were expanded and differentiated into IPCs. HLA-A2-positive humanized mice (NOG-EXL) were divided into 4 groups: diabetic mice transplanted with IPCs, diabetic but nontransplanted mice, nondiabetic mice transplanted with IPCs and normal untreated mice. Three million differentiated cells were transplanted under the renal capsule. Animals were followed-up to determine their weight, glucose levels (2-h postprandial), and human and mouse insulin levels. The mice were euthanized 6-8 weeks posttransplant. The kidneys were explanted for immunohistochemical studies. Blood, spleen and bone marrow samples were obtained to determine the proportion of immune cell subsets (CD4+, CD8+, CD16+, CD19+ and CD69+), and the expression levels of HLA-ABC and HLA-DR. RESULTS: Following STZ induction, blood glucose levels increased sharply and were then normalized within 2 weeks after cell transplantation. In these animals, human insulin levels were measurable while mouse insulin levels were negligible throughout the observation period. Immunostaining of cell-bearing kidneys revealed sparse CD45+ cells. Immunolabeling and flow cytometry of blood, bone marrow and splenic samples obtained from the 3 groups of animals did not reveal a significant difference in the proportions of immune cell subsets or in the expression levels of HLA-ABC and HLA-DR. CONCLUSION: Transplantation of IPCs derived from allogenic hAT-MSCs into humanized mice was followed by a muted allogenic immune response that did not interfere with the functionality of the engrafted cells. Our findings suggest that such allogenic cells could offer an opportunity for cell therapy for insulin-dependent diabetes without immunosuppression, encapsulation or gene manipulations.


Asunto(s)
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Células Madre Mesenquimatosas , Animales , Diferenciación Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/terapia , Antígeno HLA-A2/metabolismo , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Madre Mesenquimatosas/metabolismo , Ratones , Células Madre/metabolismo
2.
Front Immunol ; 12: 690623, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34248981

RESUMEN

Mesenchymal stem cell (MSC)-based therapy for type 1 diabetes mellitus (T1DM) has been the subject matter of many studies over the past few decades. The wide availability, negligible teratogenic risks and differentiation potential of MSCs promise a therapeutic alternative to traditional exogenous insulin injections or pancreatic transplantation. However, conflicting arguments have been reported regarding the immunological profile of MSCs. While some studies support their immune-privileged, immunomodulatory status and successful use in the treatment of several immune-mediated diseases, others maintain that allogeneic MSCs trigger immune responses, especially following differentiation or in vivo transplantation. In this review, the intricate mechanisms by which MSCs exert their immunomodulatory functions and the influencing variables are critically addressed. Furthermore, proposed avenues to enhance these effects, including cytokine pretreatment, coadministration of mTOR inhibitors, the use of Tregs and gene manipulation, are presented. As an alternative, the selection of high-benefit, low-risk donors based on HLA matching, PD-L1 expression and the absence of donor-specific antibodies (DSAs) are also discussed. Finally, the necessity for the transplantation of human MSC (hMSC)-derived insulin-producing cells (IPCs) into humanized mice is highlighted since this strategy may provide further insights into future clinical applications.


Asunto(s)
Glucemia/metabolismo , Diferenciación Celular , Diabetes Mellitus Tipo 1/cirugía , Células Secretoras de Insulina/trasplante , Insulina/metabolismo , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Animales , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/inmunología , Humanos , Células Secretoras de Insulina/inmunología , Células Secretoras de Insulina/metabolismo , Células Madre Mesenquimatosas/inmunología , Fenotipo
4.
Biomed Res Int ; 2020: 7103053, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32051828

RESUMEN

Mesenchymal stem cells (MSCs) can be differentiated in vitro to form insulin-producing cells (IPCs). However, the proportion of induced cells is modest. Extracts from injured pancreata of rodents promoted this differentiation, and three upregulated proteins were identified in these extracts. The aim of this study was to evaluate the potential benefits of adding these proteins to the differentiation medium alone or in combination. Our results indicate that the proportion of IPCs among the protein(s)-supplemented samples was significantly higher than that in the samples with no added proteins. The yield from samples supplemented with PRDX6 alone was 4-fold higher than that from samples without added protein. These findings were also supported by the results of fluorophotometry. Gene expression profiles revealed higher levels among protein-supplemented samples. Significantly higher levels of GGT, SST, Glut-2, and MafB expression were noted among PRDX6-treated samples. There was a stepwise increase in the release of insulin and c-peptide, as a function of increasing glucose concentrations, indicating that the differentiated cells were glucose sensitive and insulin responsive. PRDX6 exerts its beneficial effects as a result of its biological antioxidant properties. Considering its ease of use as a single protein, PRDX6 is now routinely used in our differentiation protocols.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Insulina/biosíntesis , Células Madre Mesenquimatosas/metabolismo , Peroxiredoxina VI/metabolismo , Peroxiredoxina VI/farmacología , Péptido C/metabolismo , Glucosa/metabolismo , Transportador de Glucosa de Tipo 2/metabolismo , Humanos , Factor de Transcripción MafB/metabolismo , Peroxiredoxina VI/genética , Somatostatina/metabolismo , Transcriptoma , gamma-Glutamiltransferasa/metabolismo
5.
Cell Transplant ; 27(6): 937-947, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29860900

RESUMEN

Ten mongrel dogs were used in this study. Diabetes was chemically induced in 7 dogs, and 3 dogs served as normal controls. For each diabetic dog, 5 million human bone marrow-derived mesenchymal stem cells/kg were differentiated to form insulin-producing cells using a trichostatin-based protocol. Cells were then loaded in 2 TheraCyte capsules which were transplanted under the rectus sheath. One dog died 4 d postoperatively from pneumonia. Six dogs were followed up with for 6 to 18 mo. Euglycemia was achieved in 4 dogs. Their glucose tolerance curves exhibited a normal pattern demonstrating that the encapsulated cells were glucose sensitive and insulin responsive. In the remaining 2 dogs, the fasting blood sugar levels were reduced but did not reach normal values. The sera of all transplanted dogs contained human insulin and C-peptide with a negligible amount of canine insulin. Removal of the transplanted capsules was followed by prompt return of diabetes. Intracytoplasmic insulin granules were seen by immunofluorescence in cells from the harvested capsules. Furthermore, all pancreatic endocrine genes were expressed. This study demonstrated that the TheraCyte capsule or a similar device can provide adequate immunoisolation, an important issue when stem cells are considered for the treatment of type 1 diabetes mellitus.


Asunto(s)
Células Madre Adultas/citología , Diferenciación Celular , Diabetes Mellitus Tipo 1/terapia , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/trasplante , Células Madre Mesenquimatosas/citología , Adulto , Animales , Células de la Médula Ósea/citología , Separación Celular , Células Cultivadas , Células Inmovilizadas/citología , Células Inmovilizadas/trasplante , Diabetes Mellitus Tipo 1/patología , Perros , Humanos , Masculino , Adulto Joven
6.
J Genet Eng Biotechnol ; 16(2): 433-440, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30733757

RESUMEN

Mesenchymal stem cells (MSCs) is a heterogeneous population. Muse cells is a rare pluripotent subpopulation within MSCs. This study aims to evaluate the pulirpotency and the ability of Muse cells to generate insulin producing cells (IPCs) after in vitro differentiation protocol compared to the non-Muse cells. Muse cells were isolated by FACSAria III cell sorter from adipose-derived MSCs and were evaluated for its pluripotency. Following in vitro differentiation, IPCs derived from Muse and non-Muse cells were evaluated for insulin production. Muse cells comprised 3.2 ±â€¯0.7% of MSCs, approximately 82% of Muse cells were positive for anti stage-specific embryonic antigen-3 (SSEA-3). Pluripotent markers were highly expressed in Muse versus non-Muse cells. The percentage of generated IPCs by flow cytometric analysis was higher in Muse cells. Under confocal microscopy, Muse cells expressed insulin and c-peptide while it was undetected in non-Muse cells. Our results introduced Muse cells as a new adult pluripotent subpopulation, which is capable to produce higher number of functional IPCs.

7.
Biomed Res Int ; 2017: 3854232, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28584815

RESUMEN

The aim of this study is to compare human bone marrow-derived mesenchymal stem cells (BM-MSCs) and adipose tissue-derived mesenchymal stem cells (AT-MSCs), for their differentiation potentials to form insulin-producing cells. BM-MSCs were obtained during elective orthotopic surgery and AT-MSCs from fatty aspirates during elective cosmetics procedures. Following their expansion, cells were characterized by phenotyping, trilineage differentiation ability, and basal gene expression of pluripotency genes and for their metabolic characteristics. Cells were differentiated according to a Trichostatin-A based protocol. The differentiated cells were evaluated by immunocytochemistry staining for insulin and c-peptide. In addition the expression of relevant pancreatic endocrine genes was determined. The release of insulin and c-peptide in response to a glucose challenge was also quantitated. There were some differences in basal gene expression and metabolic characteristics. After differentiation the proportion of the resulting insulin-producing cells (IPCs), was comparable among both cell sources. Again, there were no differences neither in the levels of gene expression nor in the amounts of insulin and c-peptide release as a function of glucose challenge. The properties, availability, and abundance of AT-MSCs render them well-suited for applications in regenerative medicine. Conclusion. BM-MSCs and AT-MSCs are comparable regarding their differential potential to form IPCs. The availability and properties of AT-MSCs render them well-suited for applications in regenerative medicine.


Asunto(s)
Tejido Adiposo/metabolismo , Células de la Médula Ósea/metabolismo , Péptido C/metabolismo , Diferenciación Celular , Insulina/metabolismo , Células Madre Mesenquimatosas/metabolismo , Tejido Adiposo/citología , Células de la Médula Ósea/citología , Humanos , Secreción de Insulina , Células Madre Mesenquimatosas/citología
8.
BJU Int ; 119(1): 142-147, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27686059

RESUMEN

OBJECTIVE: To evaluate the protective effects of selenium with vitamins A, C and E (selenium ACE, i.e. antioxidants), verapamil (calcium channel blocker), and losartan (angiotensin receptor blocker) against extracorporeal shockwave lithotripsy (ESWL)-induced renal injury. PATIENTS AND METHODS: A randomised controlled trial was conducted between August 2012 and February 2015. Inclusion criteria were adult patients with a single renal stone (<2 cm) suitable for ESWL. Patients with diabetes, hypertension, congenital renal anomalies, moderate or marked hydronephrosis, or preoperative albuminuria (>300 mg/L) were excluded. ESWL was performed using the electromagnetic DoLiS lithotripter. Eligible patients were randomised into one of four groups using sealed closed envelopes: Group1, control; Group 2, selenium ACE; Group 3, losartan; and Group 4, verapamil. Albuminuria and urinary neutrophil gelatinase-associated lipocalin (uNGAL) were estimated after 2-4 h and 1 week after ESWL. The primary outcome was differences between albuminuria and uNGAL. Dynamic contrast-enhanced magnetic resonance imaging was performed before ESWL, and at 2-4 h and 1 week after ESWL to compare changes in renal perfusion. RESULTS: Of 329 patients assessed for eligibility, the final analysis comprised 160 patients (40 in each group). Losartan was the only medication that showed significantly lower levels of albuminuria after 1 week (P < 0.001). For perfusion changes, there was a statistically significant decrease in the renal perfusion in patients with obstructed kidneys in comparison to before ESWL (P = 0.003). These significant changes were present in the control or antioxidant group, whilst in the losartan and verapamil groups renal perfusion was not significantly decreased. CONCLUSIONS: Losartan was found to protect the kidney against ESWL-induced renal injury by significantly decreasing post-ESWL albuminuria. Verapamil and losartan maintained renal perfusion in patients with post-ESWL renal obstruction.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Antioxidantes/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Riñón/lesiones , Litotricia/efectos adversos , Losartán/uso terapéutico , Selenio/uso terapéutico , Verapamilo/uso terapéutico , Vitaminas/uso terapéutico , Adulto , Ácido Ascórbico/uso terapéutico , Quimioterapia Combinada , Femenino , Humanos , Masculino , Vitamina A/uso terapéutico , Vitamina E/uso terapéutico , Heridas y Lesiones/prevención & control
9.
J Trace Elem Med Biol ; 36: 52-6, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27259352

RESUMEN

Deficiency of essential trace elements (such as Cu or Zn) and accumulation of potentially toxic trace elements (as Cd or Pb) are both known to have adverse effects in hemodialysis (HD) patients. Up to our knowledge, no studies about the permeability of low and high flux polysulfone membranes on metal ions during hemodialysis are available. Therefore, the aim of the present study was to address this issue. Forty one hemodialysis patients (19 were using high flux polysulfone membrane while the remaining were using low flux one) participated in the study. Blood levels of Cu, Zn, Cd and Pb were determined by graphite furnace atomic absorption spectrometry among HD patients, before and after dialysis session, as well as among matched 40 healthy persons. Blood concentrations of Cu and Zn in the whole hemodialysis group was significantly lower than those of the healthy control group, on the other hand the toxic metals (Cd and Pb) levels were observed to be significantly higher among HD patients compared to the normal persons. Among the hemodialysis group, there were no significant differences between the low and high flux dialyzer groups in terms of pre-dialysis blood levels of Cu, Zn, Cd and Pb. In addition, significantly decreased levels of all metal ions were observed after dialysis sessions using either low or high flux membranes. An exception was Pb which did not show any difference between pre-dialysis and post-dialysis values in the low flux groupIn conclusion Zn and Cu deficiencies should be considered in the treatment of these patients. High flux membranes are more efficient than low flux ones in removing excess Cd and Pb. Therefore, when high flux membranes are used, chelation therapy might not be required for Cd and Pb overload.


Asunto(s)
Diálisis Renal/instrumentación , Oligoelementos/sangre , Oligoelementos/aislamiento & purificación , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Biomed Res Int ; 2015: 575837, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26064925

RESUMEN

The aim of this study was to provide evidence for further in vivo maturation of insulin-producing cells (IPCs) derived from human bone marrow-derived mesenchymal stem cells (HBM-MSCs). HBM-MSCs were obtained from three insulin-dependent type 2 diabetic volunteers. Following expansion, cells were differentiated according to a trichostatin-A/GLP protocol. One million cells were transplanted under the renal capsule of 29 diabetic nude mice. Blood glucose, serum human insulin and c-peptide levels, and glucose tolerance curves were determined. Mice were euthanized 1, 2, 4, or 12 weeks after transplantation. IPC-bearing kidneys were immunolabeled, number of IPCs was counted, and expression of relevant genes was determined. At the end of in vitro differentiation, all pancreatic endocrine genes were expressed, albeit at very low values. The percentage of IPCs among transplanted cells was small (≤3%). Diabetic animals became euglycemic 8 ± 3 days after transplantation. Thereafter, the percentage of IPCs reached a mean of ~18% at 4 weeks. Relative gene expression of insulin, glucagon, and somatostatin showed a parallel increase. The ability of the transplanted cells to induce euglycemia was due to their further maturation in the favorable in vivo microenvironment. Elucidation of the exact mechanism(s) involved requires further investigation.


Asunto(s)
Diferenciación Celular/genética , Diabetes Mellitus Experimental/terapia , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Trasplante de Células Madre Mesenquimatosas , Animales , Glucemia , Células de la Médula Ósea/citología , Diabetes Mellitus Experimental/patología , Glucagón/metabolismo , Humanos , Secreción de Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Trasplante de Islotes Pancreáticos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos NOD
11.
Artículo en Inglés | MEDLINE | ID: mdl-25953570

RESUMEN

Hydroxyapatite nanorods (HAPNRs) were prepared from recycled eggshell by using precipitation method. The structure of the HAPNRs was physicochemically and morphologically characterized by X-ray diffraction, transmission electron microscopy and Fourier transform infrared spectroscopy. The resulting HAPNRs were used for solid phase extractive preconcentration of Cu(2+), Zn(2+) and Pb(2+) prior to its determination by flame atomic absorption spectrometry. Experimental variables that influence the quantitative extraction of metal ions were optimized by both batch and column methods. The analytes were quantitatively sorbed on the matrix between pHs6 and 9. The maximum sorption capacity of the HAPNRs has been found to be 2.43, 2.37 and 2.53 mmol g(-1) for Cu(2+), Zn(2+) and Pb(2+), respectively, with the preconcentration factor of 250. The 3σ detection limit and 10σ quantification limit for Cu(2+), Zn(2+) and Pb(2+) were found to be 0.72, 0.55 and 5.12 µg L(-1) and 2.40, 1.83 and 17.06 µg L(-1), respectively. The calibration curves were linear up to 250 µg L(-1) for Cu(2+), 300 µg L(-1) for Zn(2+) and 400 µg L(-1) for Pb(2+). Accuracy of the proposed method was verified using certified reference materials (NCS ZC85006 Tomato, Seronorm Trace Elements Whole Blood L-1, Seronorm Trace Elements Whole Blood L-3 and Seronorm Trace Elements Urine). The present method was successfully applied to the analysis of these metal ions in sea water, biological and food samples.


Asunto(s)
Cobre/análisis , Durapatita/química , Plomo/análisis , Nanotubos/química , Zinc/análisis , Extracción en Fase Sólida , Espectrofotometría Atómica
12.
Biomed Res Int ; 2014: 832736, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24818157

RESUMEN

INTRODUCTION: Many protocols were utilized for directed differentiation of mesenchymal stem cells (MSCs) to form insulin-producing cells (IPCs). We compared the relative efficiency of three differentiation protocols. METHODS: Human bone marrow-derived MSCs (HBM-MSCs) were obtained from three insulin-dependent type 2 diabetic patients. Differentiation into IPCs was carried out by three protocols: conophylline-based (one-step protocol), trichostatin-A-based (two-step protocol), and ß -mercaptoethanol-based (three-step protocol). At the end of differentiation, cells were evaluated by immunolabeling for insulin production, expression of pancreatic endocrine genes, and release of insulin and c-peptide in response to increasing glucose concentrations. RESULTS: By immunolabeling, the proportion of generated IPCs was modest ( ≃ 3%) in all the three protocols. All relevant pancreatic endocrine genes, insulin, glucagon, and somatostatin, were expressed. There was a stepwise increase in insulin and c-peptide release in response to glucose challenge, but the released amounts were low when compared with those of pancreatic islets. CONCLUSION: The yield of functional IPCs following directed differentiation of HBM-MSCs was modest and was comparable among the three tested protocols. Protocols for directed differentiation of MSCs need further optimization in order to be clinically meaningful. To this end, addition of an extracellular matrix and/or a suitable template should be attempted.


Asunto(s)
Células de la Médula Ósea/citología , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Insulina/biosíntesis , Células Madre Mesenquimatosas/citología , Adulto , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Péptido C/metabolismo , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Humanos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Persona de Mediana Edad , Fenotipo
13.
Biomed Res Int ; 2013: 912413, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23878820

RESUMEN

INTRODUCTION: The aim of this report is to study the graft and patient survival in a large cohort of recipients with an analysis of factors that may affect the final outcomes. METHODS: Between March 1976 and March 2008, 1967 consecutive live-donor renal transplants were carried out. Various variables that may have an impact on patients and/or graft survival were studied in two steps. Initially, a univariate analysis was carried out. Thereafter, significant variables were embedded in a stepwise regression analysis. RESULTS: The overall graft survival was 86.7% and 65.5%, at 5 and 10 years, respectively. The projected half-life for grafts was 17.5 years and for patients was 22 years. Five factors had an independent negative impact on graft survival: donor's age, genetic considerations, the type of primary immunosuppression, number of acute rejection episodes, and total steroid dose during the first 3 months after transplantation. CONCLUSIONS: Despite refinements in tissue matching techniques and improvements in immunosuppression protocols, an important proportion of grafts is still lost following living donor kidney transplantation, presumably due to chronic allograft nephropathy.


Asunto(s)
Rechazo de Injerto/mortalidad , Supervivencia de Injerto , Trasplante de Riñón/mortalidad , Donadores Vivos/estadística & datos numéricos , Complicaciones Posoperatorias/mortalidad , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Egipto/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
14.
Cell Transplant ; 22(1): 133-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22710060

RESUMEN

Harvesting, expansion, and directed differentiation of human bone marrow-derived mesenchymal stem cells (BM-MSCs) could provide an autologous source of surrogate ß-cells that would alleviate the limitations of availability and/or allogenic rejection following pancreatic or islet transplantation. Bone marrow cells were obtained from three adult type 2 diabetic volunteers and three nondiabetic donors. After 3 days in culture, adherent MSCs were expanded for two passages. At passage 3, differentiation was carried out in a three-staged procedure. Cells were cultured in a glucose-rich medium containing several activation and growth factors. Cells were evaluated in vitro by flow cytometry, immunolabeling, RT-PCR, and human insulin and c-peptide release in responses to increasing glucose concentrations. One thousand cell clusters were inserted under the renal capsule of diabetic nude mice followed by monitoring of their diabetic status. At the end of differentiation, ∼5-10% of cells were immunofluorescent for insulin, c-peptide or glucagon; insulin, and c-peptide were coexpressed. Nanogold immunolabeling for electron microscopy demonstrated the presence of c-peptide in the rough endoplasmic reticulum. Insulin-producing cells (IPCs) expressed transcription factors and genes of pancreatic hormones similar to those expressed by pancreatic islets. There was a stepwise increase in human insulin and c-peptide release by IPCs in response to increasing glucose concentrations. Transplantation of IPCs into nude diabetic mice resulted in control of their diabetic status for 3 months. The sera of IPC-transplanted mice contained human insulin and c-peptide but negligible levels of mouse insulin. When the IPC-bearing kidneys were removed, rapid return of diabetic state was noted. BM-MSCs from diabetic and nondiabetic human subjects could be differentiated without genetic manipulation to form IPCs that, when transplanted, could maintain euglycemia in diabetic mice for 3 months. Optimization of the culture conditions are required to improve the yield of IPCs and their functional performance.


Asunto(s)
Células de la Médula Ósea/metabolismo , Diabetes Mellitus Experimental/cirugía , Células Secretoras de Insulina/trasplante , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Adulto , Animales , Células de la Médula Ósea/citología , Diferenciación Celular , Femenino , Expresión Génica , Humanos , Insulina/biosíntesis , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad
15.
Exp Clin Transplant ; 9(5): 295-301, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21967254

RESUMEN

OBJECTIVES: This prospective study was designed to develop a steroid and calcineurin inhibitor-free regimen for kidney transplants using alemtuzumab. MATERIALS AND METHODS: A single dose of alemtuzumab (30 mg) was given preoperatively. Phase 1: Twenty-one patients were randomized into 2 groups; the tacrolimus (n=11) and the sirolimus groups (n=10). Steroids were given for 5 days. Azathioprine (1 mg/kg) was added when white blood cells ≥ 4000 cells/cm(3). Mean follow-up was 48 ± 2.8 and 48.2 ± 1.6 months for the tacrolimus and sirolimus groups. Phase 2: Twenty patients were included and the study design was modified. Tacrolimus was given for 2 months, and was replaced by sirolimus thereafter. The mean follow-up was 28.3 ± 2.1 months. RESULTS: Phase 1: Acute rejection episodes were encountered in 5 patients of the tacrolimus versus 2 cases in the sirolimus group (P = .44). Antibody-mediated rejection was diagnosed in 2 recipients in each group. Four patients were switched from sirolimus to tacrolimus owing to resistant rejection, significant proteinuria, persistent thrombocytopenia, lymphocele, and urinary leakage. One patient was shifted from tacrolimus to sirolimus owing to Kaposi sarcoma. Glomerular filtration rate was significantly higher in the sirolimus group. Currently, 14 patients (8 tacrolimus, and 6 sirolimus) are steroid-free. One patient died from the tacrolimus group owing to fulminant hepatitis. Two grafts were lost in the sirolimus group versus 1 graft in the tacrolimus group. Phase 2: Five patients developed successfully treated borderline changes with no antibody-mediated rejection. Mean serum creatinine was 114.9 ± 17.7 µmol/L. Currently, 17 patients are steroid free and 15 of them are calcineurin inhibitor-free as well. In this phase, only 1 patient died with a functioning graft. CONCLUSIONS: This clinical trial provides a good insight into a potentially effective steroid and calcineurin inhibitor-free protocol with the use of alemtuzumab induction in combination with sirolimus.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Antineoplásicos/administración & dosificación , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Inmunosupresores/administración & dosificación , Trasplante de Riñón , Donadores Vivos , Acondicionamiento Pretrasplante/métodos , Adolescente , Adulto , Alemtuzumab , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Antineoplásicos/efectos adversos , Azatioprina/administración & dosificación , Inhibidores de la Calcineurina , Esquema de Medicación , Sustitución de Medicamentos , Quimioterapia Combinada , Egipto , Femenino , Rechazo de Injerto/inmunología , Rechazo de Injerto/mortalidad , Humanos , Inmunosupresores/efectos adversos , Trasplante de Riñón/inmunología , Trasplante de Riñón/mortalidad , Masculino , Persona de Mediana Edad , Ácido Micofenólico/administración & dosificación , Ácido Micofenólico/análogos & derivados , Estudios Prospectivos , Sirolimus/administración & dosificación , Esteroides/administración & dosificación , Tacrolimus/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
16.
Exp Clin Transplant ; 9(4): 247-51, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21819369

RESUMEN

OBJECTIVES: The effect of basiliximab induction therapy on long-term patient and graft survival is not clear. We sought to evaluate if there is any advantage to routine basiliximab induction on the long-term outcome of living-related donor kidney transplants. MATERIALS AND METHODS: One hundred adult recipients with their first kidney allograft were randomized into 2 treatment groups; 1 group received basiliximab, and the second served as a control. All patients received a maintenance triple immunosuppressive therapy (steroids, cyclosporine, microemulsion, and azathioprine). We followed them for 10 years. RESULTS: Basiliximab reduced the proportion of patients who experienced an acute rejection in the first year (18/50) when compared with the control group (31/50) (P = .009), and in 10 years (28/50) when compared with controls (37/50) (P = .059). The cumulative steroid dosage used throughout the study was significantly lower in the basiliximab group. The overall incidence of posttransplant complications was comparable among the 2 groups. There was no significant difference in patient and graft survival; 10-year patient and graft survival were 92% and 76% for basiliximab and 90% and 68% for the control group. CONCLUSIONS: Routine basiliximab induction significantly reduces the incidence of acute rejection without any noticeable effects on the long-term renal transplant outcome.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Inmunosupresores/uso terapéutico , Trasplante de Riñón , Donadores Vivos , Proteínas Recombinantes de Fusión/uso terapéutico , Adulto , Basiliximab , Distribución de Chi-Cuadrado , Quimioterapia Combinada , Egipto , Femenino , Rechazo de Injerto/inmunología , Humanos , Estimación de Kaplan-Meier , Trasplante de Riñón/inmunología , Masculino , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
17.
Exp Clin Transplant ; 7(2): 104-9, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19715514

RESUMEN

OBJECTIVES: Endothelial cells that line the vasculature are targets for immune-mediated assault through anti-endothelial cell antibodies. The aim of this work was to detect anti-endothelial cell antibodies and describe the association with kidney allograft rejection and graft survival. MATERIALS AND METHODS: The study included 60 patients who had undergone live-donor kidney transplant. Inclusion criteria included first kidney transplant, panel reactive antibody titer less than 5%, cause of end-stage renal disease not including vasculitis or systemic lupus erythematosus, and age > 18 years. Patients were classified into 2 groups: 40 patients with anti-endothelial cell antibodies (referred to as the positive group) and 20 patients without anti-endothelial cell antibodies (referred to as the negative group). RESULTS: Serum creatinine level was higher in the positive group at 1 month and 1 year (P = .04). The occurrence of acute rejection was not significantly different in the positive group (18 patients [45.0%]) compared with the negative group (5 patients [25.0%], P = .5). However, the number of acute rejection episodes was higher in the positive group (22 episodes) compared with the negative group (6 episodes, P = .04). In patients who experienced acute rejection, chronic nephropathy was more frequent in the positive group (6 of 18 patients, 33.3%) compared with the negative group (1 of 5 patients, 20.0%) (P = .03). One-year and 5-year graft survival was 91% and 79% in the positive group, and 100% and 91% in the negative group, respectively. The difference at 5 years was significant (P = .04). CONCLUSIONS: The presence of anti-endothelial cell antibodies was associated with a higher number of acute rejection episodes and lower long-term graft survival in kidney transplants. It could be an informative test to identify patients at high risk for immunological graft loss.


Asunto(s)
Autoanticuerpos/sangre , Rechazo de Injerto/epidemiología , Rechazo de Injerto/inmunología , Trasplante de Riñón/inmunología , Cuidados Preoperatorios , Adulto , Biomarcadores/sangre , Creatinina/sangre , Femenino , Estudios de Seguimiento , Rechazo de Injerto/mortalidad , Humanos , Incidencia , Estimación de Kaplan-Meier , Fallo Renal Crónico/cirugía , Masculino , Valor Predictivo de las Pruebas
18.
Eur J Intern Med ; 20(5): 490-3, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19712851

RESUMEN

BACKGROUND: Viral hepatitis is an important etiological agent of chronic hepatitis and liver disease and is a major cause of morbidity and mortality especially in Egypt since it has the highest prevalence of hepatitis C virus (HCV) infection. We aimed to assess if there is any change in the annual seroprevalence of both HCV and hepatitis B virus (HBV) infection in Egypt in the current era. METHODS: Our study included 55,922 potentially healthy asymptomatic blood donors; 52,280 males and 3642 females with mean age of 30.98+/-8.6 years. All of them were volunteers for the first time and 70% were from rural areas. We applied our own questionnaire that included past medical history, surgical history, and history of blood donation. We screened their sera for the presence or absence of anti-HCV antibodies with the 3rd generation enzyme-linked immunosorbent assay (ELISA) and the presence or absence of hepatitis B surface antigen (HBsAg) with ELISA. RESULTS: The cumulative seroprevalence of HCV and HBV infection was 11.95% and 1.3% respectively. The annual seroprevalence of both viruses showed a declining pattern throughout the study period from 17.7% to 7.4% regarding HCV and HBV infection from 2.3% to 0.9%. The decline trends for both viral infections were observed for both genders. CONCLUSION: This study carries a glimmer of hope because of a decline in seroprevalence of viral hepatitis in Egypt. However stringent implementation of infection control programs in Egypt is mandatory to face this furious health problem.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Adulto , Control de Enfermedades Transmisibles/organización & administración , Estudios Transversales , Egipto/epidemiología , Femenino , Hepatitis B/complicaciones , Hepatitis B/diagnóstico , Hepatitis C/complicaciones , Hepatitis C/diagnóstico , Humanos , Masculino , Estudios Seroepidemiológicos , Distribución por Sexo , Adulto Joven
19.
Clin Exp Nephrol ; 13(1): 66-72, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18716711

RESUMEN

BACKGROUND/AIM: This retrospective study was conducted to assess the efficacy and safety of immunosuppression conversion on progression of chronic allograft nephropathy (CAN). METHODS: One-hundred and seventy-four cyclosporin (CsA)-treated renal transplant recipients were studied. Patients were included if they had a biopsy-proven CAN (mild to moderate) with serum creatinine < or =3.5 mg/dL. Patient treatment was switched to either: (A) MMF/reduced dose CsA (MMF for azathioprine (Aza); n = 132); or (B) Aza/Tac for CsA (n = 42). Patient records were checked for graft function and survival, and for co-morbidities after conversion. RESULTS: Mean follow-up before conversion was 52.2 +/- 31.1 and 47.9 +/- 27.4 months for groups A and B, respectively. There was significant deterioration of graft function in group B after five years (P < 0.5). Ten-year actuarial graft survival was 38% in group A and 19% in group B (P = 0.04). Nine patients (five patients and four patients in groups A and B, respectively) started dialysis within 12 months. Tacrolimus-treated patients had a lower insignificant incidence of hyperlipidemia (P = 0.05), but a significantly higher incidence of diabetes mellitus (P = 0.04).There was no significant change or difference in blood pressure between groups. CONCLUSIONS: Our results suggest that in patients with CAN and deteriorating allograft function, CsA minimization and addition of MMF achieved favorable efficacies in retarding the decline of graft function. Further prospective studies with larger cohorts are needed for validation.


Asunto(s)
Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Inmunosupresores/administración & dosificación , Enfermedades Renales/tratamiento farmacológico , Trasplante de Riñón/efectos adversos , Adulto , Azatioprina/administración & dosificación , Enfermedad Crónica , Ciclosporina/administración & dosificación , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Rechazo de Injerto/etiología , Humanos , Inmunosupresores/efectos adversos , Estimación de Kaplan-Meier , Enfermedades Renales/etiología , Enfermedades Renales/fisiopatología , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Ácido Micofenólico/administración & dosificación , Ácido Micofenólico/análogos & derivados , Estudios Retrospectivos , Tacrolimus/administración & dosificación , Factores de Tiempo , Trasplante Homólogo , Resultado del Tratamiento
20.
Nephrology (Carlton) ; 14(2): 255-61, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19017277

RESUMEN

AIM: Mycophenolate mofetil (MMF) is a powerful immunosuppressive drug with established efficacy and safety. The long-term use of MMF may bring increased risk of for infection and malignancy and also increased cost of transplantation. The search for minimization of immunosuppressive protocol has led to an open randomized clinical trial of conversion from MMF to azathioprine (AZA). METHODS: A total of 50 kidney allograft recipients treated with prednisone, sirolimus and MMF were randomized into two groups: converted (AZA group) and continuing (MMF group). The average duration of MMF therapy prior to conversion was 43 months in each group. Inclusion criteria included: patients with serum creatinine levels of less than 200 micromol/L; no past history of acute vascular rejection or recent acute rejection 6 months before randomization; and normal liver function tests. RESULTS: Baseline demographics were similar in the two groups. During the 12 month observation period, there were no acute rejection episodes in either group. There were no significant differences in overall patient or graft survival or function. AZA-treated patients had a lower incidence of gastrointestinal complications (P=0.03). Daily cost reduction in the AZA group was more than $US8.79/day per patient. CONCLUSION: In general, replacing MMF with AZA in stable renal transplant recipients is well tolerated and was cost effective with no increased risk of rejection. As the this study was on relatively small samples, larger and longer follow-up studies will be needed to confirm these expected advantages for the long-term outcome and to assess the long-term safety of this minimization of immunosuppressive therapy.


Asunto(s)
Azatioprina/uso terapéutico , Inmunosupresores/uso terapéutico , Trasplante de Riñón , Ácido Micofenólico/análogos & derivados , Sirolimus/uso terapéutico , Adulto , Azatioprina/efectos adversos , Costos y Análisis de Costo , Femenino , Humanos , Riñón/efectos de los fármacos , Riñón/fisiopatología , Trasplante de Riñón/mortalidad , Masculino , Ácido Micofenólico/efectos adversos , Ácido Micofenólico/uso terapéutico , Estudios Prospectivos
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