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1.
PLoS One ; 18(8): e0290460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37616230

RESUMO

Novel biotherapies for Type 1 Diabetes that provide a significantly expanded donor pool and that deliver all islet hormones without requiring anti-rejection drugs are urgently needed. Scoring systems have improved islet allotransplantation outcomes, but their use may potentially result in the waste of valuable cells for novel therapies. To address these issues, we created "Neo-Islets" (NIs), islet-sized organoids, by co-culturing in ultralow adhesion flasks culture-expanded islet (ICs) and Mesenchymal Stromal Cells (MSCs) (x 24 hrs, 1:1 ratio). The MSCs exert powerful immune- and cyto-protective, anti-inflammatory, proangiogenic, and other beneficial actions in NIs. The robust in vitro expansion of all islet hormone-producing cells is coupled to their expected progressive de-differentiation mediated by serum-induced cell cycle entry and Epithelial-Mesenchymal Transition (EMT). Re-differentiation in vivo of the ICs and resumption of their physiological functions occurs by reversal of EMT and serum withdrawal-induced exit from the cell cycle. Accordingly, we reported that allogeneic, i.p.-administered NIs engraft in the omentum, increase Treg numbers and reestablish permanent normoglycemia in autoimmune diabetic NOD mice without immunosuppression. Our FDA-guided pilot study (INAD 012-0776) in insulin-dependent pet dogs showed similar responses, and both human- and canine-NIs established normoglycemia in STZ-diabetic NOD/SCID mice even though the utilized islets would be scored as unsuitable for transplantation. The present study further demonstrates that islet gene expression profiles (α, ß, γ, δ) in human "non-clinical grade" islets obtained from diverse, non-diabetic human and canine donors (n = 6 each) closely correlate with population doublings, and the in vivo re-differentiation of endocrine islet cells clearly corresponds with the reestablishment of euglycemia in diabetic mice. Conclusion: human-NIs created from diverse, "non-clinical grade" donors have the potential to greatly expand patient access to this curative therapy of T1DM, facilitated by the efficient in vitro expansion of ICs that can produce ~ 270 therapeutic NI doses per donor for 70 kg recipients.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Transplante de Células-Tronco Hematopoéticas , Ilhotas Pancreáticas , Animais , Cães , Humanos , Camundongos , Camundongos SCID , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Experimental/terapia , Projetos Piloto , Camundongos Endogâmicos NOD , Doadores de Tecidos , Terapia Biológica , Organoides
3.
PLoS One ; 16(10): e0259043, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34710142

RESUMO

Globally, individuals with autoimmune Type 1 diabetes mellitus (T1DM) continue to depend for survival on insulin injections. While pancreas and intrahepatic pancreatic islet transplants can produce insulin-independence and ameliorate serious complications, both therapies depend on potentially toxic anti-rejection drugs. Furthermore, the scarcity of pancreas donors and islet transplant failures limit the general availability of such interventions. Recently, fetal and induced Pluripotent Stem Cells have been successfully differentiated to generate insulin producing ß-like cells that generate euglycemia in diabetic mice. However, their clinical use still depends on anti-rejection drugs or immune-isolating encapsulation systems. We reported recently that allogeneic "Neo-Islets" (NI), 3-D organoids of Mesenchymal Stromal and Islet Cells are immune protected and permanently correct autoimmune diabetes in NOD mice by omental engraftment and endocrine cell redifferentiation. This new "endocrine pancreas" delivers islet hormones physiologically into the hepatic portal vein. Furthermore, treatment of insulin-dependent dogs with allogeneic canine NIs (ongoing FDA-approved Pilot Study) consistently improved glycemic control without the need for antirejection drugs. As there remains a critical need for curative therapies of T1DM, we engineered human NIs and tested their ability, after i.p. administration, to reestablish euglycemia in streptozotocin (STZ)-diabetic NOD/SCID mice. This diabetes model reproduces, in part, the clinical situation in which recipients of allogeneic biotherapies must take potent anti-rejection drugs that similarly create a life-long immune-compromised status. The present study demonstrates that human NI therapy (2x10e5/kg bw NIs/mouse) of STZ-diabetic NOD/SCID mice (n = 6), compared to controls (n = 6) significantly improved glycemic control, and most importantly, that a second dose given to the initial group normalized blood glucose levels long-term. Conclusion: Despite the limitations of the utilized diabetic NOD/SCID mouse model, the obtained data show that human NIs are curative, an observation that has high translational relevance and significantly supports the planned conduct of clinical trials with human NIs.


Assuntos
Glicemia , Diabetes Mellitus Experimental/sangue , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Células-Tronco Mesenquimais , Animais , Sobrevivência de Enxerto , Humanos , Injeções Intraperitoneais , Camundongos , Organoides
4.
Artigo em Inglês | MEDLINE | ID: mdl-32792355

RESUMO

INTRODUCTION: Diabetic hyperglycemia causes progressive and generalized damage to the microvasculature. In renal glomeruli, this results in the loss of podocytes with consequent loss of constitutive angiopoietin-1 (Ang1) signaling, which is required for stability of the glomerular endothelium. Repeated tail vein injection of adenovirus expressing COMP-Ang1 (a stable bioengineered form of Ang1) was previously reported to improve diabetic glomerular damage despite the liver and lungs being primary targets of adenoviral infection. We thus hypothesized that localizing delivery of sustained COMP-Ang1 to the kidney could increase its therapeutic efficacy and safety for the treatment of diabetes. RESEARCH DESIGN AND METHODS: Using AAVrh10 adeno-associated viral capsid with enhanced kidney tropism, we treated 10-week-old uninephrectomized db/db mice (a model of type 2 diabetes) with a single dose of AAVrh10.COMP-Ang1 delivered via the intracarotid artery, compared with untreated diabetic db/db control and non-diabetic db/m mice. RESULTS: Surprisingly, both glomerular and pancreatic capillaries expressed COMP-Ang1, compensating for diabetes-induced loss of tissue Ang1. Importantly, treatment with AAVrh10.COMP-Ang1 yielded a significant reduction of glycemia (blood glucose, 241±193 mg/dL vs 576±31 mg/dL; glycosylated hemoglobin, 7.2±1.5% vs 11.3±1.3%) and slowed the progression of albuminuria and glomerulosclerosis in db/db mice by 70% and 61%, respectively, compared with untreated diabetic db/db mice. Furthermore, COMP-Ang1 ameliorated diabetes-induced increases of NF-kBp65, nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase-2 (Nox2), p47phox and productions of myeloperoxidase, the inflammatory markers in both renal and pancreatic tissues, and improved beta-cell density in pancreatic islets. CONCLUSIONS: These results highlight the potential of localized Ang1 therapy for treatment of diabetic visceropathies and provide a mechanistic explanation for reported improvements in glucose control via Ang1/Tie2 signaling in the pancreas.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ilhotas Pancreáticas , Angiopoietina-1/genética , Animais , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/terapia , Rim , Camundongos
5.
PLoS One ; 14(9): e0218688, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31536503

RESUMO

We previously reported that allogeneic, intraperitoneally administered "Neo-Islets," composed of cultured pancreatic islet cells co-aggregated with high numbers of immunoprotective and cytoprotective Adipose-derived Stem Cells, reestablished, through omental engraftment, redifferentiation and splenic and omental up-regulation of regulatory T-cells, normoglycemia in autoimmune Type-1 Diabetic Non-Obese Diabetic (NOD) mice without the use of immunosuppressive agents or encapsulation devices. Based on these observations, we are currently testing this Neo-Islet technology in an FDA guided pilot study (INAD 012-776) in insulin-dependent, spontaneously diabetic pet dogs by ultrasound-guided, intraperitoneal administration of 2x10e5 Neo-Islets/kilogram body weight to metabolically controlled (blood glucose, triglycerides, thyroid and adrenal functions) and sedated animals. We report here interim observations on the first 4 canine Neo-Islet-treated, insulin-dependent pet dogs that are now in the early to intermediate-term follow-up phase of the planned 3 year study (> 6 months post treatment). Current results from this translational study indicate that in dogs, Neo-Islets appear to engraft, redifferentiate and physiologically produce insulin, and are rejected by neither auto- nor allo-immune responses, as evidenced by (a) an absent IgG response to the allogeneic cells contained in the administered Neo-Islets, and (b) progressively improved glycemic control that achieves up to a 50% reduction in daily insulin needs paralleled by a statistically significant decrease in serum glucose concentrations. This is accomplished without the use of anti-rejection drugs or encapsulation devices. No adverse or serious adverse events related to the Neo-Islet administration have been observed to date. We conclude that this minimally invasive therapy has significant translational relevance to veterinary and clinical Type 1 diabetes mellitus by achieving complete and at this point partial glycemic control in two species, i.e., diabetic mice and dogs, respectively.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Diabetes Mellitus Tipo 1/veterinária , Doenças do Cão/terapia , Transplante das Ilhotas Pancreáticas , Animais , Biomarcadores , Glicemia , Terapia Baseada em Transplante de Células e Tecidos/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Diabetes Mellitus Experimental , Doenças do Cão/imunologia , Doenças do Cão/metabolismo , Cães , Feminino , Perfilação da Expressão Gênica , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas/efeitos adversos , Transplante das Ilhotas Pancreáticas/métodos , Isoanticorpos/imunologia , Masculino , Células-Tronco/citologia , Células-Tronco/metabolismo
6.
Stem Cells Transl Med ; 6(7): 1631-1643, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28467694

RESUMO

Novel interventions that reestablish endogenous insulin secretion and thereby halt progressive end-organ damage and prolong survival of patients with autoimmune Type 1 diabetes mellitus (T1DM) are urgently needed. While this is currently accomplished with allogeneic pancreas or islet transplants, their utility is significantly limited by both the scarcity of organ donors and life-long need for often-toxic antirejection drugs. Coadministering islets with bone marrow-derived mesenchymal stem cells (MSCs) that exert robust immune-modulating, anti-inflammatory, anti-apoptotic, and angiogenic actions, improves intrahepatic islet survival and function. Encapsulation of insulin-producing cells to prevent immune destruction has shown both promise and failures. Recently, stem cell-derived insulin secreting ß-like cells induced euglycemia in diabetic animals, although their clinical use would still require encapsulation or anti-rejection drugs. Instead of focusing on further improvements in islet transplantation, we demonstrate here that the intraperitoneal administration of islet-sized "Neo-Islets" (NIs), generated by in vitro coaggregation of allogeneic, culture-expanded islet cells with high numbers of immuno-protective and cyto-protective MSCs, resulted in their omental engraftment in immune-competent, spontaneously diabetic nonobese diabetic (NOD) mice. This achieved long-term glycemic control without immunosuppression and without hypoglycemia. In preparation for an Food and Drug Administration-approved clinical trial in dogs with T1DM, we show that treatment of streptozotocin-diabetic NOD/severe combined immunodeficiency mice with identically formed canine NIs produced durable euglycemia, exclusively mediated by dog-specific insulin. We conclude that this novel technology has significant translational relevance for canine and potentially clinical T1DM as it effectively addresses both the organ donor scarcity (>80 therapeutic NI doses/donor pancreas can be generated) and completely eliminates the need for immunosuppression. Stem Cells Translational Medicine 2017;6:1631-1643.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Animais , Células Cultivadas , Cães , Feminino , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante Homólogo/métodos
7.
Oncotarget ; 7(31): 48963-48977, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27374092

RESUMO

Bone marrow mesenchymal stromal cells (MSC) have anti-inflammatory, anti-apoptotic and immunosuppressive properties and are a potent source for cell therapy. Cell fusion has been proposed for rapid generation of functional new reprogrammed cells. In this study, we aimed to establish a fusion protocol of bone marrow-derived human MSCs with the rat beta-cell line (INS-1E) as well as human isolated pancreatic islets in order to generate insulin producing beta-MSCs as a cell-based treatment for diabetes.Human eGFP+ puromycin+ MSCs were co-cultured with either stably mCherry-expressing rat INS-1E cells or human dispersed islet cells and treated with phytohemagglutinin (PHA-P) and polyethylene glycol (PEG) to induce fusion. MSCs and fused cells were selected by puromycin treatment.With an improved fusion protocol, 29.8 ± 2.9% of all MSCs were ß-MSC heterokaryons based on double positivity for mCherry and eGFP.After fusion and puromycin selection, human NKX6.1 and insulin as well as rat Neurod1, Nkx2.2, MafA, Pdx1 and Ins1 mRNA were highly elevated in fused human MSC/INS-1E cells, compared to the mixed control population. Such induction of beta-cell markers was confirmed in fused human MSC/human dispersed islet cells, which showed elevated NEUROD1, NKX2.2, MAFA, PDX1 and insulin mRNA compared to the mixed control. Fused cells had higher insulin content and improved insulin secretion compared to the mixed control and insulin positive beta-MSCs also expressed nuclear PDX1. We established a protocol for fusion of human MSCs and beta cells, which resulted in a beta cell like phenotype. This could be a novel tool for cell-based therapies of diabetes.


Assuntos
Fusão Celular/métodos , Células Secretoras de Insulina/citologia , Células-Tronco Mesenquimais/citologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células da Medula Óssea , Diferenciação Celular , Separação Celular , Técnicas de Cocultura , Feminino , Glucose/química , Proteínas de Fluorescência Verde/metabolismo , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodomínio , Humanos , Insulina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares , Fenótipo , Fito-Hemaglutininas/química , Polietilenoglicóis/química , Ratos , Fatores de Transcrição
8.
J Am Soc Nephrol ; 27(11): 3394-3404, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26984884

RESUMO

Erythropoietin (EPO) may be a beneficial tissue-protective cytokine. However, high doses of EPO are associate with adverse effects, including thrombosis, tumor growth, and hypertension. Carbamylated erythropoietin (CEPO) lacks both erythropoietic and vasoconstrictive actions. In this study, we compared the renoprotective, hemodynamic, and hematologic activities and survival effects of identical EPO and CEPO doses in rat models of clinically relevant AKI presentations, including ischemia-reperfusion-induced AKI superimposed on CKD (5000 U/kg EPO or CEPO; three subcutaneous injections) and ischemia-reperfusion-induced AKI in old versus young animals and male versus female animals (1000 U/kg EPO or CEPO; three subcutaneous injections). Compared with EPO therapy, CEPO therapy induced greater improvements in renal function and body weight in AKI on CKD animals, with smaller increases in hematocrit levels and similarly improved survival. Compared with EPO therapy in the other AKI groups, CEPO therapy induced greater improvements in protection and recovery of renal function and survival, with smaller increases in systolic BP and hematocrit levels. Overall, old or male animals had more severe loss in kidney function and higher mortality rates than young or female animals, respectively. Notably, mRNA and protein expression analyses confirmed the renal expression of the heterodimeric EPO receptor/CD131 complex, which is required for the tissue-protective effects of CEPO signaling. In conclusion, CEPO improves renal function, body and kidney weight, and survival in AKI models without raising hematocrit levels and BP as substantially as EPO. Thus, CEPO therapy may be superior to EPO in improving outcomes in common forms of clinical AKI.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Eritropoetina/análogos & derivados , Eritropoetina/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Fatores Etários , Animais , Feminino , Masculino , Ratos , Ratos Endogâmicos F344 , Fatores Sexuais
10.
F1000Prime Rep ; 6: 83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25343040

RESUMO

Acute kidney injury (AKI) is a common clinical entity associated with high morbidity and mortality and clinical costs. The pathophysiology is multifaceted and involves inflammation, tubular injury, and vascular damage. Recently identified components include necroptosis, a special form of cell death, and autophagy. Most of the pathophysiological knowledge is obtained from animal models but these do not directly reflect the reality of the clinical situation. Tubular cells have a remarkable capacity to regenerate, and the role of stem/progenitor cells is discussed. Acute kidney injury is frequently associated with chronic kidney disease, and the implications are widespread.

12.
Am J Kidney Dis ; 60(6): 1012-22, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23036928

RESUMO

Acute kidney injury (AKI) is a common clinical entity with high morbidity and mortality rates and ever increasing medical costs. A large number of patients who are hospitalized with morbidities such as diabetes, vascular disease, or chronic kidney disease are at high risk to develop AKI due to ischemic and nephrotoxic insults. The pathophysiology of ischemic and toxic forms of AKI is complex and includes tubular and vascular cell damage and inflammation. Given the seriousness of this essentially therapy-resistant complication, treatment beyond supportive measures and renal replacement therapy is urgently needed. Recent stem cell research has shown promising results, and cell therapy-based interventions are advancing into clinical trials. An example is our phase 1 clinical trial (NCT00733876) in which cardiac surgery patients at high risk of postoperative AKI were treated safely with allogeneic mesenchymal stem cells. Together with the introduction of biomarkers for an earlier and specific AKI diagnosis, currently tested stem cell-based therapies are expected to provide an entirely new class of diagnostic and therapeutic tools.


Assuntos
Injúria Renal Aguda/fisiopatologia , Injúria Renal Aguda/terapia , Rim/fisiologia , Transplante de Células-Tronco Mesenquimais/métodos , Regeneração/fisiologia , Injúria Renal Aguda/diagnóstico , Idoso , Ensaios Clínicos Fase I como Assunto/tendências , Humanos , Masculino , Diálise Renal/métodos
13.
Kidney Int ; 81(10): 939-941, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22543903

RESUMO

Because pharmacological interventions for the treatment of acute kidney injury (AKI) have remained ineffective, cell-based therapies have been developed. Marrow stromal cells have been found to be safe and potentially effective in study subjects. Jung et al. demonstrate that macrophages made to overexpress anti-inflammatory interleukin-10 protect rats with AKI through iron-mediated upregulation of lipocalin-2 and its receptors, eliciting both anti-inflammatory and proliferative responses. These data further advance our understanding of cell-based therapies for AKI.


Assuntos
Injúria Renal Aguda/prevenção & controle , Transferência Adotiva , Interleucina-10/biossíntese , Isquemia/terapia , Rim/metabolismo , Lipocalinas/metabolismo , Macrófagos/transplante , Traumatismo por Reperfusão/prevenção & controle , Animais , Humanos , Lipocalina-2 , Masculino
14.
Clin J Am Soc Nephrol ; 7(5): 844-50, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22442182

RESUMO

Acute kidney injury (AKI) remains a complex clinical problem associated with significant short-term morbidity and mortality and lacking effective pharmacologic interventions. Patients with AKI experience longer-term risks for progressive chronic ESRD, which diminish patients' health-related quality of life and create a larger burden on the healthcare system. Although experimental models have yielded numerous promising agents, translation into clinical practice has been unsuccessful, possibly because of issues in clinical trial design, such as delayed drug administration, masking of therapeutic benefit by adverse events, and inadequate sample size. To address issues of clinical trial design, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored a workshop titled "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers" in December 2010. Workshop participants included representatives from academia, industry, and government agencies whose areas of expertise spanned basic science, clinical nephrology, critical care medicine, biostatistics, pharmacology, and drug development. This document summarizes the discussions of collaborative workgroups that addressed issues related to patient selection, study endpoints, the role of novel biomarkers, sample size and power calculations, and adverse events and pilot/feasibility studies in prevention and treatment of AKI. Companion articles outline the discussions of workgroups for model trials related to prevention or treatment of established AKI in different clinical settings, such as in patients with sepsis.


Assuntos
Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Ensaios Clínicos como Assunto/métodos , Biomarcadores , Determinação de Ponto Final , Estudos de Viabilidade , Humanos , Seleção de Pacientes , Projetos Piloto , Tamanho da Amostra , Estatística como Assunto
15.
Clin J Am Soc Nephrol ; 7(5): 856-60, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22442184

RESUMO

AKI remains an important clinical problem, with a high mortality rate, increasing incidence, and no Food and Drug Administration-approved therapeutics. Advances in addressing this clinical need require approaches for rapid diagnosis and stratification of injury, development of therapeutic agents based on precise understanding of key pathophysiological events, and implementation of well designed clinical trials. In the near future, AKI biomarkers may facilitate trial design. To address these issues, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored a meeting, "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers," in December of 2010 that brought together academic investigators, industry partners, and representatives from the National Institutes of Health and the Food and Drug Administration. Important issues in the design of clinical trials for interventions in AKI in patients with sepsis or AKI in the setting of critical illness after surgery or trauma were discussed. The sepsis working group discussed use of severity of illness scores and focus on patients with specific etiologies to enhance homogeneity of trial participants. The group also discussed endpoints congruent with those endpoints used in critical care studies. The second workgroup emphasized difficulties in obtaining consent before admission and collaboration among interdisciplinary healthcare groups. Despite the difficult trial design issues, these clinical situations represent a clinical opportunity because of the high event rates, severity of AKI, and poor outcomes. The groups considered trial design issues and discussed advantages and disadvantages of several short- and long-term primary endpoints in these patients.


Assuntos
Injúria Renal Aguda/terapia , Ensaios Clínicos como Assunto/métodos , Sepse/complicações , Injúria Renal Aguda/complicações , Injúria Renal Aguda/diagnóstico , Cuidados Críticos , Estado Terminal , Determinação de Ponto Final , Humanos , Consentimento Livre e Esclarecido , Seleção de Pacientes , Período Pós-Operatório , Índice de Gravidade de Doença , Ferimentos e Lesões/complicações
16.
Clin J Am Soc Nephrol ; 7(5): 851-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22442188

RESUMO

AKI is an important clinical problem that has become increasingly more common. Mortality rates associated with AKI remain high despite advances in supportive care. Patients surviving AKI have increased long-term mortality and appear to be at increased risk of developing CKD and progressing to ESRD. No proven effective pharmacologic therapies are currently available for the prevention or treatment of AKI. Advances in addressing this unmet need will require the development of novel therapeutic agents based on precise understanding of key pathophysiological events and the implementation of well designed clinical trials. To address this need, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored the "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers" workshop in December 2010. The event brought together representatives from academia, industry, the National Institutes of Health, and the US Food and Drug Administration. We report the discussions of workgroups that developed outlines of clinical trials for the prevention of AKI in two patient populations: patients undergoing elective surgery who are at risk for or who develop AKI, and patients who are at risk for contrast-induced AKI. In both of these populations, primary prevention or secondary therapy can be delivered at an optimal time relative to kidney injury. The workgroups detailed primary and secondary endpoints for studies in these groups, and explored the use of adaptive clinical trial designs for trials of novel preventive strategies to improve outcomes of patients with AKI.


Assuntos
Injúria Renal Aguda/prevenção & controle , Ensaios Clínicos como Assunto/métodos , Biomarcadores , Determinação de Ponto Final , Estudos de Viabilidade , Humanos , Seleção de Pacientes , Projetos Piloto , Tamanho da Amostra , Estatística como Assunto
17.
Kidney Int ; 79(11): 1159-61, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21566636

RESUMO

Novel urinary biomarkers for the early, sensitive, and specific diagnosis of acute kidney injury (AKI) show promise for the improved management of patients with this treatment-resistant complication. Several biomarkers (Kim-1, lipocalin-2, osteopontin, gluthathione S-transferases) that were tested by Rouse et al. during gentamicin-induced AKI and its recovery possess renoprotective activities, capabilities that may guide the development of novel interventions. However, despite the increased commercial availability of biomarkers, effective therapies for clinical AKI await discovery.


Assuntos
Injúria Renal Aguda/diagnóstico , Biomarcadores/urina , Túbulos Renais Proximais/metabolismo , Proteômica , Injúria Renal Aguda/patologia , Injúria Renal Aguda/fisiopatologia , Injúria Renal Aguda/terapia , Injúria Renal Aguda/urina , Animais , Apoptose , Biomarcadores/sangue , Diagnóstico Precoce , Glutationa Transferase/urina , Humanos , Túbulos Renais Proximais/patologia , Túbulos Renais Proximais/fisiopatologia , Lipocalinas/urina , Necrose , Osteopontina/urina , Valor Preditivo dos Testes , Proteômica/métodos , Receptores Virais/metabolismo , Regeneração , Fatores de Tempo
18.
Organogenesis ; 7(2): 96-100, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21521944

RESUMO

An extensive body of preclinical and clinical data has shown that administration of adult multipotent marrow stromal cells (MSCs) effectively ameliorates experimental and clinical conditions of many different organ systems. Differentiation into organ parenchymal cells, however, is very rare, and the main mechanism for organ protection and regeneration from different types of injury is the exertion of paracrine effects and stimulation of tissue repair. A large number of clinical trials have been conducted and are ongoing to investigate the safety and efficacy of MSCs in different organs after various types of organ injury. This article intends to give a brief overview about current applications of MSCs and mechanisms involved in organ protection and regeneration.


Assuntos
Células da Medula Óssea/citologia , Regeneração Tecidual Guiada/métodos , Células-Tronco Multipotentes/citologia , Humanos , Especificidade de Órgãos , Transplante de Células-Tronco , Células Estromais/citologia
19.
Kidney Int Suppl (2011) ; 1(3): 74-76, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25018905

RESUMO

Mesenchymal stromal cells (mSCs) are presently studied for the prophylaxis and therapy of a variety of diseases such as acute graft-versus-host disease after allogeneic stem cell transplantation, cardiac indications, bone degeneration, Crohn's disease, and organ rejection, as well as prevention of acute renal failure in high-risk situations. mSCs appear to function through paracrine mechanisms that exert immunosuppressive, anti-inflammatory, anti-apoptotic, mitogenic, and other organ-protective and repair-stimulating actions. mSCs are either cultured in the presence of fetal calf serum (FCS) or platelet lysate (PL). PL lysate-generated mSCs exhibit faster doubling times, different gene expression profiles, and more potent immunosuppressive activity compared with FSC-generated mSCs. The utility of mSCs in the treatment of chronic inflammatory diseases is being evaluated in prospective studies.

20.
Kidney Int Suppl (2011) ; 1(3): 87-89, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25018907

RESUMO

Both the homing of hematopoietic stem cells (HSCs) to the bone marrow and their engraftment in recipients of bone marrow transplants are primarily mediated by the chemokine stromal-derived factor-1 (SDF-1) or CXCL12, which activates CXCR4, its cognate receptor on HSCs. We showed that the recruitment and temporary attachment of CXCR4-expressing cells, such as HSCs and a fraction of mesenchymal stem cells (MSCs), to the kidney, following ischemia/reperfusion acute kidney injury, are similarly mediated by robustly upregulated SDF-1 in the kidney, indicating that such organ injury appears to lead to the transient expression of a facultative stem cell niche. This SDF-1 response of the injured kidney facilitates both the mobilization from the bone marrow and homing of precursor cells, and other CXCR4-expressing cells such as administered MSCs, to the kidney, where they aid in its protection and repair. Similar responses have been observed subsequent to the injury of other solid organs such as the heart, liver, and brain.

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