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1.
Pediatr Surg Int ; 37(10): 1383-1392, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34245339

RESUMEN

BACKGROUND: Chronic pancreatitis (CP) and acute recurrent pancreatitis (ARP) in pediatric patients are strongly associated with genetic mutations and lead to pan-parenchymal disease refractory to medical and endoscopic treatment. Our aim was to assess pain resolution and glucose control in patients with CP and ARP following total pancreatectomy with islet auto-transplantation (TPIAT). METHODS: We retrospectively analyzed prospectively collected clinical data of 12 children who developed CP and ARP and underwent TPIAT when 21 years old or younger at the University of Chicago between December 2009 and June 2020. Patients with recurrent or persistent abdominal pain attributed to acute or chronic pancreatic inflammation and a history of medical interventions attempted for the relief of pancreatic pain were selected by a multi-disciplinary team for TPIAT. We followed patients post-operatively and reported data for pre-TPIAT, post-operative day 75, and yearly post-TPIAT. RESULTS: All 12 patients experienced complete resolution of pancreatic pain. The overall insulin-independence rate after 1 year was 66% (8/12) and 50% (3/6) at 4 years. Shorter duration of CP/ARP pre-TPIAT, higher mass of islets infused, and lower BMI, BMI percentile, and BSA were associated with insulin-independence post-TPIAT. CONCLUSIONS: TPIAT is a viable treatment option for pediatric patients with CP and ARP. Pediatric patients undergoing TPIAT for CP achieved resolution of pancreatic-type pain and reduced opioid requirements. The majority were able to achieve insulin-independence which was associated with lower pre-TPIAT BMI and higher islet mass transplanted (i.e., over 2000 IEQ/kg), the latter of which can be achieved by earlier TPIAT. LEVEL OF EVIDENCE: Treatment study, Level IV.


Asunto(s)
Glucemia , Pancreatitis Crónica , Dolor Abdominal , Niño , Humanos , Pancreatectomía , Pancreatitis Crónica/cirugía , Estudios Retrospectivos , Trasplante Autólogo , Resultado del Tratamiento
2.
Am J Transplant ; 20(3): 844-851, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31597009

RESUMEN

This study aimed to evaluate whether the BETA-2 score is a reliable early predictor of graft decline and loss of insulin independence after islet allotransplantation. Islet transplant procedures were stratified into 3 groups according to clinical outcome: long-term insulin independence without islet graft decline (group 1, N = 9), initial insulin independence with subsequent islet graft decline and loss of insulin independence (group 2, N = 13), and no insulin independence (group 3, N = 13). BETA-2 was calculated on day 75 and multiple times afterwards for up to 145 months posttransplantation. A BETA-2 score cut-off of 17.4 on day 75 posttransplantation was discerned between group 1 and groups 2 and 3 (area under the receiver operating characteristic 0.769, P = .005) with a sensitivity and negative predictive value of 100%. Additionally, BETA-2 ≥ 17.4 at any timepoint during follow-up reflected islet function required for long-term insulin independence. While BETA-2 did not decline below 17.4 for each of the 9 cases from group 1, the score decreased below 17.4 for all transplants from group 2 with subsequent loss of insulin independence. The reduction of BETA-2 below 17.4 predicted 9 (1.5-21) months in advance subsequent islet graft decline and loss of insulin independence (P = .03). This finding has important implications for posttransplant monitoring and patient care.


Asunto(s)
Diabetes Mellitus Tipo 1 , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos , Glucemia , Péptido C , Diabetes Mellitus Tipo 1/cirugía , Humanos , Insulina
3.
Transpl Int ; 32(3): 280-290, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30353611

RESUMEN

We investigated six indices based on a single fasting blood sample for evaluation of the beta-cell function after total pancreatectomy with islet autotransplantation (TP-IAT). The Secretory Unit of Islet Transplant Objects (SUITO), transplant estimated function (TEF), homeostasis model assessment (HOMA-2B%), C-peptide/glucose ratio (CP/G), C-peptide/glucose creatinine ratio (CP/GCr) and BETA-2 score were compared against a 90-min serum glucose level, weighted mean C-peptide in mixed meal tolerance test (MMTT), beta score and the Igls score adjusted for islet function in the setting of IAT. We analyzed values from 32 MMTTs in 15 patients after TP-IAT with a follow-up of up to 3 years. Four (27%) individuals had discontinued insulin completely prior to day 75, while 6 out of 12 patients (50%) did not require insulin support at 1-year follow-up with HbA1c 6.0% (5.5-6.8). BETA-2 was the most consistent among indices strongly correlating with all reference measures of beta-cell function (r = 0.62-0.68). In addition, it identified insulin independence (cut-off = 16.2) and optimal/good versus marginal islet function in the Igls score well, with AUROC of 0.85 and 0.96, respectively. Based on a single fasting blood sample, BETA-2 score has the most reliable discriminant value for the assessment of graft function in patients undergoing TP-IAT.


Asunto(s)
Ayuno/sangre , Células Secretoras de Insulina/fisiología , Trasplante de Islotes Pancreáticos , Pancreatectomía , Adolescente , Adulto , Glucemia/análisis , Péptido C/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Trasplante Autólogo , Adulto Joven
4.
Am J Transplant ; 18(4): 990-997, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29218834

RESUMEN

Six single fasting blood sample-based indices-Secretory Unit of Islet Transplant Objects (SUITO), Transplant Estimated Function (TEF), Homeostasis Model Assessment (HOMA)2-B%, C-peptide/glucose ratio (CP/G), C-peptide/glucose creatinine ratio (CP/GCr), and BETA-2 score-were compared against commonly used 90-minute mixed meal tolerance test (MMTT) serum glucose and beta score to assess which of them best recognizes the state of acceptable blood glucose control without insulin supplementation after islet allotransplantation (ITx). We also tested whether the indices could identify the success of ITx based on the Igls classification of beta cell graft function. We analyzed values from 47 MMTT tests in 4 patients with up to 140 months follow-up and from 54 MMTT tests in 13 patients with up to 42 months follow-up. SUITO, CP/G, HOMA2-B%, and BETA-2 correlated well with the 90-minute glucose of the MMTT and beta-score (r 0.54-0.76), whereas CP/GCr showed a modest performance (r 0.41-0.52) while TEF showed little correlation. BETA-2 and SUITO were the best identifiers and predictors of the need for insulin support, glucose intolerance, and ITx success (P < .001), while HOMA2-B% and TEF were unreliable. Single fasting blood sample SUITO and BETA-2 scores are very practical alternative tools that allow for frequent assessments of graft function.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/terapia , Ayuno/sangre , Supervivencia de Injerto , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/fisiología , Adulto , Glucemia/análisis , Péptido C/sangre , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad , Pronóstico
6.
Hum Mol Genet ; 24(6): 1646-54, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25398947

RESUMEN

Non-coding variation within TCF7L2 remains the strongest genetic determinant of type 2 diabetes risk in humans. A considerable effort has been placed in understanding the functional roles of TCF7L2 in pancreatic beta cells, despite evidence of TCF7L2 expression in various peripheral tissues important in glucose homeostasis. Here, we use a humanized mouse model overexpressing Tcf7l2, resulting in glucose intolerance, to infer the contribution of Tcf7l2 overexpression in beta cells and in other tissues to the metabolic phenotypes displayed by these mice. Restoring Tcf7l2 expression specifically in beta cells to endogenous levels, in face of its overexpression elsewhere, results in impaired insulin secretion, reduced beta cell number and islet area, corroborating data obtained in humans showing similar phenotypes as a result of manipulations leading to Tcf7l2 loss of function. Interestingly, the persistent overexpression of Tcf7l2 in non-pancreatic tissues results in a significant worsening in glucose tolerance in vivo, indicating that Tcf7l2 overexpression in beta cells does not account for the glucose intolerance in the Tcf7l2 overexpression mouse model. Collectively, these data posit that Tcf7l2 plays key roles in glucose metabolism through actions beyond pancreatic beta cells, and further points to functionally opposing cell-type specific effects for Tcf7l2 on the maintenance of balanced glucose metabolism, thereby urging a careful examination of its role in non-pancreatic tissues as well as its composite metabolic effects across distinct tissues. Uncovering these roles may lead to new therapeutic targets for type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Intolerancia a la Glucosa/genética , Glucosa/metabolismo , Proteína 2 Similar al Factor de Transcripción 7/genética , Animales , Modelos Animales de Enfermedad , Expresión Génica , Humanos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Masculino , Ratones , Ratones Transgénicos , Regulación hacia Arriba
7.
J Biol Chem ; 289(23): 16290-302, 2014 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-24770419

RESUMEN

Among the defects in the early events of insulin biosynthesis, proinsulin misfolding and endoplasmic reticulum (ER) stress have drawn increasing attention as causes of ß cell failure. However, no studies have yet addressed potential defects at the cytosolic entry point of preproinsulin into the secretory pathway. Here, we provide the first evidence that inefficient translocation of preproinsulin (caused by loss of a positive charge in the n region of its signal sequence) contributes to ß cell failure and diabetes. Specifically, we find that, after targeting to the ER membrane, preproinsulin signal peptide (SP) mutants associated with autosomal dominant late-onset diabetes fail to be fully translocated across the ER membrane. The newly synthesized, untranslocated preproinsulin remains strongly associated with the ER membrane, exposing its proinsulin moiety to the cytosol. Rather than accumulating in the ER and inducing ER stress, untranslocated preproinsulin accumulates in a juxtanuclear compartment distinct from the Golgi complex, induces the expression of heat shock protein 70 (HSP70), and promotes ß cell death. Restoring an N-terminal positive charge to the mutant preproinsulin SP significantly improves the translocation defect. These findings not only reveal a novel molecular pathogenesis of ß cell failure and diabetes but also provide the first evidence of the physiological and pathological significance of the SP n region positive charge of secretory proteins.


Asunto(s)
Diabetes Mellitus/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Precursores de Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Diabetes Mellitus/patología , Retículo Endoplásmico/metabolismo , Humanos , Insulina/química , Islotes Pancreáticos/patología , Ratones , Datos de Secuencia Molecular , Precursores de Proteínas/química , Transporte de Proteínas , Ratas , Homología de Secuencia de Aminoácido
8.
Eur J Transl Clin Med ; 6(1): 9-13, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37693941

RESUMEN

Pregnancy increases metabolic demand for insulin and may lead to the exhaustion of intraportally transplanted islets and post-gestational hyperglycemia. To prevent these complications, we implemented preemptive insulin supplementation during two subsequent pregnancies in an insulin-independent islet transplant recipient. This strategy resulted in optimal blood glucose control during the pregnancies, the preservation of the optimal islet graft function and the postpartum maintenance of long-term insulin independence.

9.
Ann Surg ; 254(3): 512-8; discussion 518-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21865948

RESUMEN

OBJECTIVES: To develop a novel approach for local immunoprotection using CD4(+)CD25(high)CD127(-) T regulatory cells (Tregs) attached to the surface of the islets before transplantation. BACKGROUND: Tregs expanded ex vivo can control allo and autoreactivity, therefore, Treg-based therapy may offer more effective protection for transplanted islets from immunologic attack than currently used immunosuppression. Local application of Tregs can make such therapy more clinically feasible and efficient. METHODS: Human islets were isolated and coated with allogeneic ex vivo expanded Tregs using biotin-poly(ethylene glycol)-N-hydroxysuccinimide ester (biotin-PEG-NHS) and streptavidin as binding molecules. RESULTS: Coating pancreatic islets with Tregs did not affect islet viability (>90% fluorescein diacetate/propidium iodide) or the insulin secretion profile in dynamic islet perifusion assays. After in vitro incubation with allogeneic T effector cells, Treg-coated islets revealed preserved function with higher insulin secretion compared with controls-native islets, coated islets with T effector cells or when Tregs were added to the culture, but not attached to islets (P < 0.05). In addition, the Enzyme-linked immunosorbent spot (ELISPOT) assay revealed suppression of interferon (IFN)-γ secretion, when T effector cells were challenged with Treg-coated islets comparing to controls (99 ± 7 vs 151 ± 8 dots, respectively; P < 0.01). CONCLUSIONS: We demonstrated, for the first time, the ability to bind immune regulatory cells to target cells with preservation of their viability and function and protective activity against immune attack. If successfully tested in an animal model, local delivery of immunoprotective Tregs on the surface of transplanted pancreatic islets may be an alternative or improvement to the currently used immunosuppression.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Interferón gamma/inmunología , Trasplante de Islotes Pancreáticos/inmunología , Islotes Pancreáticos/inmunología , Linfocitos T Reguladores/inmunología , Tolerancia al Trasplante , Ensayo de Immunospot Ligado a Enzimas , Estudios de Factibilidad , Humanos , Terapia de Inmunosupresión/métodos , Técnicas In Vitro , Interferón gamma/efectos de los fármacos , Tolerancia al Trasplante/inmunología
10.
J Clin Med ; 10(12)2021 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-34205321

RESUMEN

(1) Background: The correlation between titers of islet autoantibodies (IAbs) and the loss of transplanted islets remains controversial. We sought to evaluate the prognostic utility of monitoring IAbs in diabetic patients after islet transplantation (ITx); (2) Methods: Twelve patients with Type 1 diabetes mellitus and severe hypoglycemia underwent ITx. Serum concentration of glutamic acid decarboxylase (GAD), insulinoma antigen 2 (IA-2), and zinc transport 8 (ZnT8) autoantibodies was assessed before ITx and 0, 7, and 75 days and every 3 months post-operatively; (3) Results: IA-2A (IA-2 antibody) and ZnT8A (ZnT8 antibody) levels were not detectable before or after ITx in all patients (median follow-up of 53 months (range 24-61)). Prior to ITx, GAD antibody (GADA) was undetectable in 67% (8/12) of patients. Of those, 75% (6/8) converted to GADA+ after ITx. In 67% (4/6) of patients with GADA+ seroconversion, GADA level peaked within 3 months after ITx and subsequently declined. All patients with GADA+ seroconversion maintained long-term partial or complete islet function (insulin independence) after 1 or 2 ITx. There was no correlation between the presence of IAb-associated HLA haplotypes and the presence of IAbs before or after ITx; (4) Conclusions: There is no association between serum GADA trends and ITx outcomes. IA-2A and ZnT8A were not detectable in any of our patients before or after ITx.

11.
Cell Transplant ; 30: 9636897211001774, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33908301

RESUMEN

A recent randomized, multicenter trial did not show benefit of a CXCR1/2 receptor inhibitor (Reparixin) when analysis included marginal islet mass (>3,000 IEQ/kg) for allotransplantation and when immunosuppression regimens were not standardized among participating centers. We present a post-hoc analysis of trial patients from our center at the University of Chicago who received an islet mass of over 5,000 IEQ/kg and a standardized immunosuppression regimen of anti-thymocyte globulin (ATG) for induction. Twelve islet allotransplantation (ITx) recipients were randomized (2:1) to receive Reparixin (N = 8) or placebo (N = 4) in accordance with the multicenter trial protocol. Pancreas and donor characteristics did not differ between Reparixin and placebo groups. Five (62.5%) patients who received Reparixin, compared to none in the placebo group, achieved insulin independence after only one islet infusion and remained insulin-free for over 2 years (P = 0.08). Following the first ITx with ATG induction, distinct cytokine, chemokine, and miR-375 release profiles were observed for both the Reparixin and placebo groups. After excluding procedures with complications, islet engraftment on post-operative day 75 after a single transplant was higher in the Reparixin group (n = 7) than in the placebo (n = 3) group (P = 0.03) when islet graft function was measured by the ratio of the area under the curve (AUC) for c-peptide to glucose in mixed meal tolerance test (MMTT). Additionally, the rate of engraftment was higher when determined via BETA-2 score instead of MMTT (P = 0.01). Our analysis suggests that Reparixin may have improved outcomes compared to placebo when sufficient islet mass is transplanted and when standardized immunosuppression with ATG is used for induction. However, further studies are warranted. Investigation of Reparixin and other novel agents under more standardized and optimized conditions would help exclude confounding factors and allow for a more definitive evaluation of their role in improving outcomes in islet transplantation. Clinical trial reg. no. NCT01817959, clinicaltrials.gov.


Asunto(s)
Inmunosupresores/uso terapéutico , Trasplante de Islotes Pancreáticos/métodos , Alotrasplante Compuesto Vascularizado/métodos , Adulto , Animales , Chicago , Método Doble Ciego , Femenino , Humanos , Inmunosupresores/farmacología , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Estudios Prospectivos , Estados Unidos
12.
J Clin Med ; 10(13)2021 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-34209541

RESUMEN

The Food and Drug Administration (FDA) has been regulating human islets for allotransplantation as a biologic drug in the US. Consequently, the requirement of a biological license application (BLA) approval before clinical use of islet transplantation as a standard of care procedure has stalled the development of the field for the last 20 years. Herein, we provide our commentary to the multiple FDA's position papers and guidance for industry arguing that BLA requirement has been inappropriately applied to allogeneic islets, which was delivered to the FDA Cellular, Tissue and Gene Therapies Advisory Committee on 15 April 2021. We provided evidence that BLA requirement and drug related regulations are inadequate in reassuring islet product quality and potency as well as patient safety and clinical outcomes. As leaders in the field of transplantation and endocrinology under the "Islets for US Collaborative" designation, we examined the current regulatory status of islet transplantation in the US and identified several anticipated negative consequences of the BLA approval. In our commentary we also offer an alternative pathway for islet transplantation under the regulatory framework for organ transplantation, which would address deficiencies of in current system.

13.
J Pancreatol ; 3(2): 86-92, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33005475

RESUMEN

Total pancreatectomy with islet autotransplantation (TPIAT) is an effective treatment option for non-diabetic patients with intractable chronic pancreatitis. The outcome and potential benefits for pre-diabetic and diabetic patients are less well established. Thirty-four patients underwent TPIAT were retrospectively divided into 3 groups according to pre-operative glycemic control: diabetes mellitus (DM) (n=5, 15%), pre-DM (n=11, 32%) and non-DM (n=18, 54%). Pre-operative fasting c-peptide was detectable and similar in all 3 groups. Islet yield in the DM group was comparable to pre-DM and non-DM groups (median islet equivalents [IEQ] was 191,800, 111,800, and 232,000IEQ, respectively). Patients received islet mass of over the target level of 2000IEQ/kg in pre-DM and DM at lower but clinically meaningful rates compared to the non-DM group: 45% (5/11) and 60% (3/5) for a combined 50% (8/16) rate, respectively, compared to 83% (15/18) for the non-DM group. At 1 year, fasting c-peptide and HbA1c did not differ between DM and pre-DM groups but c-peptide was significantly higher in non-DM. Islet transplantation failed (negative c-peptide) only in 1 patient. Pre-operatively, all patients experienced pancreatic pain with daily opioid dependence in 60% to 70%. Pancreatic-type pain gradually subsided completely in all groups with no differences in other painful somatic symptoms. Diabetic patients with measurable pre-operative c-peptide can achieve similar benefit from TPIAT, with comparable outcomes to pre-diabetic and non-diabetic patients including pain relief and the metabolic benefit of transplanted islets. Not surprisingly, endocrine outcomes for diabetic and pre-diabetics patients are substantially worse than in those with normal pre-operative glucose control.

14.
J Gastrointest Surg ; 23(11): 2201-2210, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30719679

RESUMEN

INTRODUCTION: We assessed whether positive microbiological cultures from the islet preparation had any effect on the risk of infectious complications (IC) after total pancreatectomy with islet autotransplantation (TPIAT) in our center. METHODS: We analyzed preservation fluid and final islet product surveillance cultures with reference to clinical data of patients undergoing TPIAT. All patients received routine prophylactic broad-spectrum antibiotics. RESULTS: The study involved 10 men and 18 women with a median age of 39 years. Over 30% of surveillance cultures during pancreas processing grew bacterial strains with predominantly polymicrobial contaminations (13 of 22 (59%)). At least one positive culture was identified in almost half of the patients (46%) undergoing TPIAT and a third had both surveillance cultures positive. Infectious complications affected 50% of patients. After excluding cases of PICC line-associated bacteremia/fungemia present on admission, incidence of IC was higher in cases of positive final islet product culture than in those with negative result (57% vs. 21%), which also corresponded with the duration of chronic pancreatitis (p = 0.04). Surgical site infections were the most common IC, followed by fever of unknown origin. There was no concordance between pathogens isolated from the pancreas and those identified during the infection. CONCLUSIONS: While IC was common among TPIAT patients, we found no concordance between pathogens isolated from the pancreas and those identified during infection. Contamination of the final islet product was of clinical importance and could represent a surrogate marker for higher susceptibility to infection.


Asunto(s)
Trasplante de Islotes Pancreáticos/efectos adversos , Pancreatectomía/efectos adversos , Pancreatitis Crónica/cirugía , Infección de la Herida Quirúrgica/etiología , Adolescente , Adulto , Niño , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/epidemiología , Factores de Tiempo , Trasplante Autólogo , Estados Unidos/epidemiología , Adulto Joven
15.
Cell Transplant ; 28(2): 185-194, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30520321

RESUMEN

The selection of optimal pancreas donors is one of the key factors in determining the ultimate outcome of clinical islet isolation. North American Islet Donor Score (NAIDS) allows for estimating the chance of the success of islet isolation. It was developed based on the data from over 1000 donors from 11 islet isolation centers and validated in the University of Alberta, Edmonton, on the cohort from the most active islet transplant center. Now we aimed to also validate it in our much less active program. Areas under the receiver operating characteristic curves (AUROCs) and logistic regression analyses were obtained to test if NAIDS would better predict successful islet isolation (defined as post-purification islet yield >400,000 islet equivalents (IEQ)) than previously described Edmonton islet donor score (IDS) and our modified version of IDS. We analyzed the donor scores with reference to 82 of our islet isolation outcomes. The success rate increased proportionally as NAIDS increased, from 0% success in NAIDS < 50 points to 40% success in NAIDS ≥ 80 points. AUROCs were 0.67 (95% confidence interval (CI) 0.55-0.79) for NAIDS, 0.58 (95% CI 0.44-0.71) for modified IDS, and 0.51 (95% CI 0.37-0.65) for IDS and did not differ significantly. However, based on logistic regression analyses, NAIDS was the only statistically significant predictor of successful isolation (p = 0.01). The main advantage of NAIDS is an enhanced ability to discriminate poor-quality donors than previously used scoring systems at University of Chicago, with 0% chance for success when NAIDS was <50 as compared with 40% success rate for IDS <50. NAIDS was found to be the most useful available tool for donor pancreas selection in clinical and research practice in our center, allowing for identification and rejection of poor-quality donors, saving time and resources.


Asunto(s)
Trasplante de Islotes Pancreáticos/estadística & datos numéricos , Páncreas/cirugía , Adulto , Selección de Donante , Humanos , Modelos Logísticos , América del Norte
16.
Transplantation ; 86(3): 478-81, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18698254

RESUMEN

Recent advances in nanotechnology and molecular self-assembly may provide novel solutions to current cell transplantation deficiencies. Heparin-binding peptide amphiphiles (HBPAs) self-assemble from aqueous media into nanofibers that bind growth factors through interactions with the bioactive polymer heparin. In this report, we demonstrate that delivery of vascular endothelial growth factor and fibroblast growth factor-2 from HBPA scaffolds significantly increases blood vessel density in the mouse omentum over control scaffolds without growth factors (P<0.0005) and significantly enhances islet engraftment. Diabetic recipients transplanted with 250 isologous islets and HBPA scaffolds containing vascular endothelial growth factor/fibroblast growth factor-2 achieved normoglycemia at a higher rate (78%) than control animals receiving identical scaffolds without growth factors (30%; P<0.05) or growth factors alone (20%). These data indicate that the enhanced engraftment can be attributed to specific growth factor effects that were made possible by the delivery mechanism of HBPA nanostructures.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Factor 2 de Crecimiento de Fibroblastos/farmacología , Heparina/metabolismo , Trasplante de Islotes Pancreáticos , Nanoestructuras , Péptidos/metabolismo , Andamios del Tejido , Factor A de Crecimiento Endotelial Vascular/farmacología , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Diabetes Mellitus Experimental/cirugía , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Humanos , Masculino , Ratones , Ratones Transgénicos , Neovascularización Fisiológica/efectos de los fármacos , Epiplón/irrigación sanguínea , Epiplón/cirugía , Péptidos/química , Proteínas Recombinantes/metabolismo , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
17.
Cell Transplant ; 26(1): 33-44, 2017 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-27524672

RESUMEN

This study investigates manufacturing procedures that affect islet isolation outcomes from donor pancreata standardized by the North American Islet Donor Score (NAIDS). Islet isolations performed at the University of Illinois, Chicago, from pancreata with NAIDS ≥65 were investigated. The research cohort was categorized into two groups based on a postpurification yield either greater than (group A) or less than (group B) 400,000 IEQ. Associations between manufacturing procedures and islet isolation outcomes were analyzed using multivariate logistic or linear regressions. A total of 119 cases were retrieved from 630 islet isolations performed since 2003. Group A is composed of 40 cases with an average postpurified yield of 570,098 IEQ, whereas group B comprised 79 cases with an average yield of 235,987 IEQ. One third of 119 cases were considered successful islet isolations that yielded >400,000 IEQ. The prepurified and postpurified islet product outcome parameters were detailed for future reference. The NAIDS (>80 vs. 65-80) [odds ratio (OR): 2.91, 95% confidence interval (CI): 1.27-6.70], cold ischemic time (≤10 vs. >10 h) (OR: 3.68, 95% CI: 1.61-8.39), and enzyme perfusion method (mechanical vs. manual) (OR: 2.38, 95% CI: 1.01-5.56) were independent determinants for postpurified islet yield ≥400,000 IEQ. The NAIDS (>80, p < 0.001), cold ischemic time (≤10 h, p < 0.05), increased unit of collagenase (p < 0.01), and pancreatic duct cannulation time (<30 min, p < 0.01) all independently correlated with better islet quantity parameters. Furthermore, cold ischemic time (≤10 h, p < 0.05), liberase MTF (p < 0.001), increased unit of collagenase (p < 0.05), duct cannulation time (<30 min, p < 0.05), and mechanical enzyme perfusion (p < 0.05) were independently associated with better islet morphology score. Analysis of islet manufacturing procedures from the pancreata with standardized quality is essential in identifying technical issues within islet isolation. Adequate processing duration in each step of islet isolation, using liberase MTF, and mechanical enzyme perfusion all affect isolation outcomes.


Asunto(s)
Trasplante de Islotes Pancreáticos/normas , Islotes Pancreáticos/cirugía , Donantes de Tejidos/estadística & datos numéricos , Adulto , Anciano , Glucemia , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , América del Norte , Páncreas
18.
Cell Transplant ; 25(7): 1219-25, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26610269

RESUMEN

Quantity and quality assessment of human pancreatic islets are essential processes to define a safe and potent quality product used for clinical transplantation. The conventional method of manual assessment has been used in the field for longer than two decades. The high degree of variability in product quantity and lack of archival imaging records of the product for verification are two major disadvantages of using the manual method for quantity and quality assessment of human pancreatic islets. Investigators have developed promising new methods for technical improvement. In this study, we briefly review the published methods and highlight the advantages of digital imaging analysis (DIA) when compared to the manual method. The application of DIA reduces measurement variability and increases the precision of islet equivalent (IEQ) determination for batch analysis. It produces images that can be archived for retrospective analysis and validation, and the data can be transmitted electronically for off-site analysis. These features are important for quality pancreatic islet assessment and are consistent with FDA requirements of current good manufacturing practice for clinical islet transplantation.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Islotes Pancreáticos/anatomía & histología , Animales , Color , Humanos
19.
Diabetes ; 65(11): 3418-3428, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27465220

RESUMEN

Eight manufacturing facilities participating in the National Institutes of Health-sponsored Clinical Islet Transplantation (CIT) Consortium jointly developed and implemented a harmonized process for the manufacture of allogeneic purified human pancreatic islet (PHPI) product evaluated in a phase 3 trial in subjects with type 1 diabetes. Manufacturing was controlled by a common master production batch record, standard operating procedures that included acceptance criteria for deceased donor organ pancreata and critical raw materials, PHPI product specifications, certificate of analysis, and test methods. The process was compliant with Current Good Manufacturing Practices and Current Good Tissue Practices. This report describes the manufacturing process for 75 PHPI clinical lots and summarizes the results, including lot release. The results demonstrate the feasibility of implementing a harmonized process at multiple facilities for the manufacture of a complex cellular product. The quality systems and regulatory and operational strategies developed by the CIT Consortium yielded product lots that met the prespecified characteristics of safety, purity, potency, and identity and were successfully transplanted into 48 subjects. No adverse events attributable to the product and no cases of primary nonfunction were observed.


Asunto(s)
Trasplante de Islotes Pancreáticos/métodos , Adolescente , Adulto , Anciano , Femenino , Humanos , Islotes Pancreáticos , Trasplante de Islotes Pancreáticos/economía , Masculino , Persona de Mediana Edad , National Institutes of Health (U.S.) , Estados Unidos , Adulto Joven
20.
Cell Transplant ; 25(8): 1515-1523, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26922947

RESUMEN

Selection of an optimal donor pancreas is the first key task for successful islet isolation. We conducted a retrospective multicenter study in 11 centers in North America to develop an islet donor scoring system using donor variables. The data set consisting of 1,056 deceased donors was used for development of a scoring system to predict islet isolation success (defined as postpurification islet yield >400,000 islet equivalents). With the aid of univariate logistic regression analyses, we developed the North American Islet Donor Score (NAIDS) ranging from 0 to 100 points. The c index in the development cohort was 0.73 (95% confidence interval 0.70-0.76). The success rate increased proportionally as the NAIDS increased, from 6.8% success in the NAIDS < 50 points to 53.7% success in the NAIDS ≥ 80 points. We further validated the NAIDS using a separate set of data consisting of 179 islet isolations. A comparable outcome of the NAIDS was observed in the validation cohort. The NAIDS may be a useful tool for donor pancreas selection in clinical practice. Apart from its utility in clinical decision making, the NAIDS may also be used in a research setting as a standardized measurement of pancreas quality.


Asunto(s)
Trasplante de Islotes Pancreáticos/métodos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Páncreas/cirugía , Estudios Retrospectivos , Donantes de Tejidos , Adulto Joven
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