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1.
Physiol Rev ; 98(3): 1143-1167, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717931

RESUMO

Diabetes mellitus results from disturbed glucose homeostasis due to an absolute (type 1) or relative (type 2) deficiency of insulin, a peptide hormone almost exclusively produced by the beta cells of the endocrine pancreas in a tightly regulated manner. Current therapy only delays disease progression through insulin injection and/or oral medications that increase insulin secretion or sensitivity, decrease hepatic glucose production, or promote glucosuria. These drugs have turned diabetes into a chronic disease as they do not solve the underlying beta cell defects or entirely prevent the long-term complications of hyperglycemia. Beta cell replacement through islet transplantation is a more physiological therapeutic alternative but is severely hampered by donor shortage and immune rejection. A curative strategy should combine newer approaches to immunomodulation with beta cell replacement. Success of this approach depends on the development of practical methods for generating beta cells, either in vitro or in situ through beta cell replication or beta cell differentiation. This review provides an overview of human beta cell generation.


Assuntos
Técnicas de Cultura de Células , Células Secretoras de Insulina/fisiologia , Regeneração , Animais , Homeostase , Humanos , Células Secretoras de Insulina/transplante
2.
Diabetologia ; 59(9): 1948-58, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27318836

RESUMO

AIMS/HYPOTHESIS: When the beta cell mass or function declines beyond a critical point, hyperglycaemia arises. Little is known about the potential pathways involved in beta cell rescue. As two cytokines, epidermal growth factor (EGF) and ciliary neurotrophic factor (CNTF), restored a functional beta cell mass in mice with long-term hyperglycaemia by reprogramming acinar cells that transiently expressed neurogenin 3 (NGN3), the current study assesses the effect of these cytokines on the functional beta cell mass after an acute chemical toxic insult. METHODS: Glycaemia and insulin levels, pro-endocrine gene expression and beta cell origin, as well as the role of signal transducer and activator of transcription 3 (STAT3) signalling, were assessed in EGF+CNTF-treated mice following acute hyperglycaemia. RESULTS: The mice were hyperglycaemic 1 day following i.v. injection of the beta cell toxin alloxan, when the two cytokines were applied. One week later, 68.6 ± 4.6% of the mice had responded to the cytokine treatment and increased their insulin(+) cell number to 30% that of normoglycaemic control mice, resulting in restoration of euglycaemia. Although insulin(-) NGN3(+) cells appeared following acute EGF+CNTF treatment, genetic lineage tracing showed that the majority of the insulin(+) cells originated from pre-existing beta cells. Beta cell rescue by EGF+CNTF depends on glycaemia rather than on STAT3-induced NGN3 expression in acinar cells. CONCLUSIONS/INTERPRETATION: In adult mice, EGF+CNTF allows the rescue of beta cells in distress when treatment is given shortly after the diabetogenic insult. The rescued beta cells restore a functional beta cell mass able to control normal blood glucose levels. These findings may provide new insights into compensatory pathways activated early after beta cell loss.


Assuntos
Fator Neurotrófico Ciliar/uso terapêutico , Fator de Crescimento Epidérmico/uso terapêutico , Hiperglicemia/tratamento farmacológico , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Aloxano/toxicidade , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Glicemia/efeitos dos fármacos , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Diabetologia ; 59(9): 1834-7, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27053238

RESUMO

The generation of beta(-like) cells to compensate for their absolute or relative shortage in type 1 and type 2 diabetes is an obvious therapeutic strategy. Patients first received grafts of donor islet cells over 25 years ago, but this procedure has not become routine in clinical practice because of a donor cell shortage and (auto)immune problems. Transplantation of differentiated embryonic and induced pluripotent stem cells may overcome some but not all the current limitations. Reprogramming exocrine cells towards functional beta(-like) cells would offer an alternative abundant and autologous source of beta(-like) cells. This review focuses on work by our research group towards achieving such a source of cells. It summarises a presentation given at the 'Can we make a better beta cell?' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Amin Ardestani and Kathrin Maedler, DOI: 10.1007/s00125-016-3892-9 , and by Heiko Lickert and colleagues, DOI: 10.1007/s00125-016-3949-9 ) and a commentary by the Session Chair, Shanta Persaud (DOI: 10.1007/s00125-016-3870-2 ).


Assuntos
Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Pâncreas/citologia , Animais , Diferenciação Celular/fisiologia , Humanos , Macrófagos/metabolismo , Fatores de Transcrição/metabolismo
4.
Cancer Chemother Pharmacol ; 92(6): 455-464, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37505272

RESUMO

The first-in-patient (FIP) starting dose for oncology agents should be reasonably safe and provide potential therapeutic benefit to the patient. For late-stage oncology patients, this dose is often based on the ICH S9 guidance, which was developed primarily based on experience with cytotoxic chemotherapeutic agents using the rodent STD10 or non-rodent HNSTD and an appropriate safety factor. With the increase in molecularly targeted chemotherapeutics, it is prudent to re-evaluate how the FIP dose is derived to ensure that the appropriate balance between risk and therapeutic benefit to the patient is achieved. Blinded data on 92 small molecule oncology compounds from 12 pharmaceutical companies who are members of the IQ DruSafe consortium were gathered to investigate if a NOAEL-based starting dose without a safety factor would have been tolerated in the FIP trial and if so, estimating how many dose escalation cohorts could have been reduced. Our analysis suggests that the NOAEL-based alternative starting dose would have been tolerated in most cases evaluated, with an anticipated mean reduction of 2.3 cohorts. Of the 12 cases where the alternative approach resulted in a starting dose that would have exceeded the MTD/RP2D, none of the nonclinical toxicities in these cases were considered irreversible and would be monitorable in all but one instance. Most non-tolerated cases were within two-threefold of the MTD/RP2D, with the clinical AEs considered manageable and mitigated by dose de-escalation. No one method of FIP dose calculation will likely be appropriate for all oncology small molecules and starting dose selection should be performed using a case-by-case approach. However, the NOAEL-based method that does not utilize a safety factor should be considered when appropriate to minimize the number of patients exposed to sub-therapeutic doses of an investigational oncology agent and accelerating development to RP2D.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Nível de Efeito Adverso não Observado , Antineoplásicos/efeitos adversos , Dose Máxima Tolerável , Neoplasias/tratamento farmacológico , Oncologia , Relação Dose-Resposta a Droga
6.
MAbs ; 11(2): 422-433, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30550367

RESUMO

Bispecific antibody production using single host cells has been a new advancement in the antibody engineering field. We previously showed comparable in vitro biological activity and in vivo mouse pharmacokinetics (PK) for two novel single cell variants (v10 and v11) and one traditional dual cell in vitro-assembled anti-human epidermal growth factor receptor 2/CD3 T-cell dependent bispecific (TDB) antibodies. Here, we extended our previous work to assess single cell-produced bispecific variants of a novel TDB against FcRH5, a B-cell lineage marker expressed on multiple myeloma (MM) tumor cells. An in vitro-assembled anti- FcRH5/CD3 TDB antibody was previously developed as a potential treatment option for MM. Two bispecific antibody variants (designs v10 and v11) for manufacturing anti-FcRH5/CD3 TDB in single cells were compared to in vitro-assembled TDB in a dual-cell process to understand whether differences in antibody design and production led to any major differences in their in vitro biological activity, in vivo mouse PK, and PK/pharmacodynamics (PD) or immunogenicity in cynomolgus monkeys (cynos). The binding, in vitro potencies, in vitro pharmacological activities and in vivo PK in mice and cynos of these single cell TDBs were comparable to those of the in vitro-assembled TDB. In addition, the single cell and in vitro-assembled TDBs exhibited robust PD activity and comparable immunogenicity in cynos. Overall, these studies demonstrate that single cell-produced and in vitro-assembled anti-FcRH5/CD3 T-cell dependent bispecific antibodies have similar in vitro and in vivo properties, and support further development of single-cell production method for anti-FcRH5/CD3 TDBs and other single-cell bispecifics.


Assuntos
Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/farmacocinética , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/farmacocinética , Receptores Fc/química , Animais , Anticorpos Biespecíficos/imunologia , Anticorpos Monoclonais Humanizados/imunologia , Complexo CD3/imunologia , Desenho de Fármacos , Humanos , Técnicas In Vitro , Macaca fascicularis , Camundongos , Mieloma Múltiplo , Linfócitos T/imunologia
8.
Nat Biotechnol ; 32(1): 76-83, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24240391

RESUMO

Reprogramming of pancreatic exocrine cells into cells resembling beta cells may provide a strategy for treating diabetes. Here we show that transient administration of epidermal growth factor and ciliary neurotrophic factor to adult mice with chronic hyperglycemia efficiently stimulates the conversion of terminally differentiated acinar cells to beta-like cells. Newly generated beta-like cells are epigenetically reprogrammed, functional and glucose responsive, and they reinstate normal glycemic control for up to 248 d. The regenerative process depends on Stat3 signaling and requires a threshold number of Neurogenin 3 (Ngn3)-expressing acinar cells. In contrast to previous work demonstrating in vivo conversion of acinar cells to beta-like cells by viral delivery of exogenous transcription factors, our approach achieves acinar-to-beta-cell reprogramming through transient cytokine exposure rather than genetic modification.


Assuntos
Fator Neurotrófico Ciliar/administração & dosagem , Diabetes Mellitus/tratamento farmacológico , Fator de Crescimento Epidérmico/administração & dosagem , Células Secretoras de Insulina/efeitos dos fármacos , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fator Neurotrófico Ciliar/genética , Diabetes Mellitus/genética , Fator de Crescimento Epidérmico/genética , Hiperglicemia/tratamento farmacológico , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Endogâmicos NOD/genética , Transdução de Sinais
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