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1.
Eur Rev Med Pharmacol Sci ; 25(12): 4435-4438, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34227081

RESUMEN

OBJECTIVE: We aimed at explaining the mechanism of therapeutic effect of Umbilical Cord Mesenchymal Stem Cells (UC-MSC) in subjects with COVID-19 Acute Respiratory Distress Syndrome (ARDS). Patients with COVID-19 ARDS present with a hyperinflammatory response characterized by high levels of circulating pro-inflammatory mediators, including tumor necrosis factor α and ß (TNFα and TNFß). Inflammatory functions of these TNFs can be inhibited by soluble TNF Receptor 2 (sTNFR2). In patients with COVID-19 ARDS, UC-MSC appear to impart a robust anti-inflammatory effect, and treatment is associated with remarkable clinical improvements. We investigated the levels of TNFα, TNFß and sTNFR2 in blood plasma samples collected from subjects with COVID-19 ARDS enrolled in our trial of UC-MSC treatment. PATIENTS AND METHODS: We analyzed plasma samples from subjects with COVID-19 ARDS (n=24) enrolled in a Phase 1/2a randomized controlled trial of UC-MSC treatment. Plasma samples were obtained at Day 0 (baseline, before UC-MSC or control infusion), and Day 6 post infusion. Plasma concentrations of sTNFR2, TNFα, and TNFß were evaluated using a quantitative multiplex protein array. RESULTS: Our data indicate that at Day 6 after infusion, UC-MSC recipients develop significantly increased levels of plasma sTNFR2 and significantly decreased levels of TNFα and TNFß, compared to controls. CONCLUSIONS: These observations suggest that sTNFR2 plays a mechanistic role in mediating UC-MSC effect on TNFα and TNFß plasma levels, determining a decrease in inflammation in COVID-19 ARDS.


Asunto(s)
COVID-19/sangre , Linfotoxina-alfa/sangre , Trasplante de Células Madre Mesenquimatosas/métodos , Receptores Tipo II del Factor de Necrosis Tumoral/sangre , Síndrome de Dificultad Respiratoria/sangre , Factor de Necrosis Tumoral alfa/sangre , Cordón Umbilical/trasplante , Biomarcadores/sangre , COVID-19/terapia , Método Doble Ciego , Humanos , Síndrome de Dificultad Respiratoria/terapia , Cordón Umbilical/citología
2.
Artículo en Inglés | MEDLINE | ID: mdl-34164564

RESUMEN

The coronavirus SARS-CoV-2 is cause of a global pandemic of a pneumonia-like disease termed Coronavirus Disease 2019 (COVID-19). COVID-19 presents a high mortality rate, estimated at 3.4%. More than 1 out of 4 hospitalized COVID-19 patients require admission to an Intensive Care Unit (ICU) for respiratory support, and a large proportion of these ICU-COVID-19 patients, between 17% and 46%, have died. In these patients COVID-19 infection causes an inflammatory response in the lungs that can progress to inflammation with cytokine storm, Acute Lung Injury (ALI), Acute Respiratory Distress Syndrome (ARDS), thromboembolic events, disseminated intravascular coagulation, organ failure, and death. Mesenchymal Stem Cells (MSCs) are potent immunomodulatory cells that recognize sites of injury, limit effector T cell reactions, and positively modulate regulatory cell populations. MSCs also stimulate local tissue regeneration via paracrine effects inducing angiogenic, anti-fibrotic and remodeling responses. MSCs can be derived in large number from the Umbilical Cord (UC). UC-MSCs, utilized in the allogeneic setting, have demonstrated safety and efficacy in clinical trials for a number of disease conditions including inflammatory and immune-based diseases. UC-MSCs have been shown to inhibit inflammation and fibrosis in the lungs and have been utilized to treat patients with severe COVID-19 in pilot, uncontrolled clinical trials, that reported promising results. UC-MSCs processed at our facility have been authorized by the FDA for clinical trials in patients with an Alzheimer's Disease, and in patients with Type 1 Diabetes (T1D). We hypothesize that UC-MSC will also exert beneficial therapeutic effects in COVID-19 patients with cytokine storm and ARDS. We propose an early phase controlled, randomized clinical trial in COVID-19 patients with ALI/ARDS. Subjects in the treatment group will be treated with two doses of UC-MSC (l00 × 106 cells). The first dose will be infused within 24 hours following study enrollment. A second dose will be administered 72 ± 6 hours after the first infusion. Subject in the control group will receive infusion of vehicle (DPBS supplemented with 1% HSA and 70 U/kg unfractionated Heparin, delivered IV) following the same timeline. Subjects will be evaluated daily during the first 6 days, then at 14, 28, 60, and 90 days following enrollment (see Schedule of Assessment for time window details). Safety will be determined by adverse events (AEs) and serious adverse events (SAEs) during the follow-up period. Efficacy will be defined by clinical outcomes, as well as a variety of pulmonary, biochemical and immunological tests. Success of the current study will provide a framework for larger controlled, randomized clinical trials and a means of accelerating a possible solution for this urgent but unmet medical need. The proposed early phase clinical trial will be performed at the University of Miami (UM), in the facilities of the Diabetes Research Institute (DRI), UHealth Intensive Care Unit (ICU) and the Clinical Translational Research Site (CTRS) at the University of Miami Miller School of Medicine and at the Jackson Memorial Hospital (JMH).

3.
Transplant Proc ; 40(2): 424-6, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18374089

RESUMEN

At the present time, transplantation of pancreatic islet cells is considered an experimental therapy for a selected cohort of patients with type 1 diabetes, and is conducted under an Investigational New Drug (IND) application. Encouraging results of the Edmonton Protocol published in the year 2000 sparked a renewed interest in clinical transplantation of allogeneic islets, triggering a large number of IND applications for phase I clinical trials. Promising results reported by a number of centers since then prompted the Food and Drug Administration (FDA) to consider the possibility of licensing allogeneic islets as a therapeutic treatment for patients with type 1 diabetes. However, prior to licensure, issues such as safety, purity, efficacy, and potency of the islet product must be addressed. This is complicated by the intricate nature of pancreatic islets and limited characterization prior to transplantation. In this context, control of the manufacturing process plays a critical role in the definition of the final product. Despite significant progress made in standardization of the donor organ preservation methods, reagents used, and characterization assays performed to qualify an islet cell product, control of the isolation process remains a challenge. Within the scope of the FDA regulations, islet cells meet the definition of a biologic product, somatic cell therapy, and a drug. In addition, AABB standards that address cellular therapy products apply to manufacturing facilities accredited by this organization. Control of the source material, isolation process, and final product are critical issues that must be addressed in the context of FDA and other relevant regulations applicable to islet cell products.


Asunto(s)
Islotes Pancreáticos/citología , Islotes Pancreáticos/fisiología , Diabetes Mellitus Tipo 1/cirugía , Humanos , Trasplante de Islotes Pancreáticos/legislación & jurisprudencia , Trasplante de Islotes Pancreáticos/métodos , Selección de Paciente , Donantes de Tejidos , Trasplante Homólogo/legislación & jurisprudencia , Estados Unidos , United States Food and Drug Administration
4.
Diabetes ; 46(7): 1120-3, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9200645

RESUMEN

Enzymatic digestion of donor pancreases is a vital step in human and large mammalian islet isolation. The variable enzymatic activities of different batches of commercially available collagenase is a major obstacle in achieving reproducibility in islet isolation procedures. In the present work, the effectiveness of Liberase, a standardized mixture of highly purified enzymes recently developed for the separation of human islets, was compared with that of a traditional collagenase preparation (type P). The results of 50 islet isolations using Liberase enzyme were compared with those of 36 isolations with collagenase, type P. No significant differences in donor age, cold ischemia time, digestion time, or weight of the pancreases were observed between the two groups. Islet yield was significantly higher in the group where the Liberase enzyme was used. All parameters examined (islet number, islet number per gram of tissue, islet equivalent number, and islet equivalent number per gram of tissue) were significantly improved when Liberase enzyme was used. Different lots of Liberase enzyme were tested, and no difference was observed. Islets isolated with Liberase enzyme were also of larger size and were much less fragmented, suggesting a gentler enzymatic action and better preservation of anatomical integrity. Islets isolated with Liberase enzyme, assessed both in vitro and in vivo, revealed a functional profile similar to that of islets separated with collagenase. Liberase enzyme appears, therefore, to represent a new powerful tool for improving the quality of human islet isolation.


Asunto(s)
Colagenasas/metabolismo , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/citología , Páncreas/metabolismo , Termolisina/metabolismo , Adulto , Animales , Glucemia/análisis , Glucemia/metabolismo , Humanos , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Páncreas/patología , Factores de Tiempo
5.
Neurology ; 57(1): 130-2, 2001 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-11445642

RESUMEN

Six patients who fulfilled strictly defined criteria for migrainous cerebral infarction and in whom other causes of stroke were ruled out were observed. All had a long-standing history of migraine with aura. In most, stroke was mild with good recovery and no recurrence. Headache frequency and severity decreased after the stroke. It is hypothesized that the improvement in migraine may be due to reduced nociceptive transmission as result of loss in vasoreactivity of the affected cerebral blood vessel.


Asunto(s)
Migraña con Aura/complicaciones , Migraña con Aura/fisiopatología , Accidente Cerebrovascular/etiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/fisiopatología
6.
Placenta ; 17(7): 431-41, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8899872

RESUMEN

We have previously demonstrated that epidermal growth factor (EGF), colony stimulating factor-1 (CSF-I), and granulocyte-monocyte colony stimulating factor (GMCSF) stimulate, while transforming growth factor beta 1 (TGF beta 1) inhibits, cytotrophoblast differentiation. To identify genes mediating EGF induced differentiation, we constructed a subtracted cDNA library between undifferentiated cytotrophoblast and differentiating cytotrophoblast. We identified six novel genes and four known syncytial products alpha-human chorionic gonadotrophin (alpha hCG) pregnancy-specific beta 1-glycoprotein, 3 beta-hydroxysteroid dehydrogenase, and plasminogen activator inhibitor type 1 whose mRNAs increased during differentiation. Ten other genes were identified whose mRNAs increased during differentiation. Five of these (keratin 19, calcreticulin, heat shock protein 27, serum and glucocorticoid-regulated kinase and adrenomedullin) were not previously reported to be expressed in placenta. Five other genes known to be expressed in placenta were identified. keratin 8, fibronectin, mitochondrial ATP synthase, 1119, and cytosolic copper-zinc superoxide dismutase (SOD-1). Several of these genes may have regulatory functions in trophoblast differentiation.


Asunto(s)
Diferenciación Celular/genética , Hibridación de Ácido Nucleico , Trofoblastos/citología , 3-Hidroxiesteroide Deshidrogenasas/genética , Factor de Crecimiento Epidérmico/farmacología , Femenino , Fibronectinas/genética , Hormonas Glicoproteicas de Subunidad alfa/genética , Humanos , Datos de Secuencia Molecular , Inhibidor 1 de Activador Plasminogénico/genética , Embarazo , Glicoproteínas beta 1 Específicas del Embarazo/genética , ARN Mensajero/metabolismo , Superóxido Dismutasa/genética
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