RESUMO
Human adipose stem cells (HASCS) play a crucial role in the fields of regenerative medicine and tissue engineering for different reasons: the abundance of adipose tissue, their easy harvesting, the ability to multipotent differentiation and the fact that they do not trigger allogeneic blood response or secrete cytokines that act as immunosuppressants. The vast majority of protocols use animal origin reagents, with the underlying risk of transmitting infections by non-human pathogens. We have designed a protocol to isolate and maintain the properties of hASCs avoiding xenogeneic reagents. These changes not only preserve hASCs morphology, but also increase cell proliferation and maintain their stem cell marker profile. On the other hand, human serum albumin (HSA), Tryple® and human Serum (HS), do not affect hASCs multipotent differentiation ability. The amendments introduced do not trigger modifications in the transcriptional profile of hASCs, alterations in key biochemical pathways or malignization. Thus, we have proven that it is possible to isolate and maintain hASCs avoiding animal reagents and, at the same time, preserving crucial culture parameters during long term culture. Thereby we have revealed a novel and effective tool for the improvement of clinical, cell-based therapies.
Assuntos
Adipócitos/citologia , Células-Tronco/citologia , Adipócitos/metabolismo , Adolescente , Adulto , Animais , Biomarcadores , Diferenciação Celular , Proliferação de Células , Separação Celular , Terapia Baseada em Transplante de Células e Tecidos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Humanos , Redes e Vias Metabólicas , Cultura Primária de Células , Medicina Regenerativa , Células-Tronco/metabolismo , Engenharia Tecidual , Adulto JovemRESUMO
Neural stem cells (NSCs) persist in the subventricular zone (SVZ) of the adult brain. Location within this germinal region determines the type of neuronal progeny NSCs generate, but the mechanism of adult NSC positional specification remains unknown. We show that sonic hedgehog (Shh) signaling, resulting in high gli1 levels, occurs in the ventral SVZ and is associated with the genesis of specific neuronal progeny. Shh is selectively produced by a small group of ventral forebrain neurons. Ablation of Shh decreases production of ventrally derived neuron types, while ectopic activation of this pathway in dorsal NSCs respecifies their progeny to deep granule interneurons and calbindin-positive periglomerular cells. These results show that Shh is necessary and sufficient for the specification of adult ventral NSCs.
Assuntos
Movimento Celular/fisiologia , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/fisiologia , Proteínas Hedgehog/metabolismo , Células-Tronco Neurais/fisiologia , Transdução de Sinais/fisiologia , Fatores Etários , Animais , Calbindinas , Colina O-Acetiltransferase/metabolismo , Citarabina/farmacologia , Antagonistas de Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Proteínas Hedgehog/genética , Imunossupressores/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Luminescentes/genética , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/metabolismo , Bulbo Olfatório/citologia , RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteína G de Ligação ao Cálcio S100/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor Smoothened , Estilbamidinas , Tamoxifeno/farmacologia , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo , Proteína GLI1 em Dedos de ZincoRESUMO
Optic nerve (ON) oligodendrocyte precursors (OPCs) are generated under the influence of the Sonic hedgehog (Shh) in the preoptic area from where they migrate to colonise the entire nerve. The molecular events that control this migration are still poorly understood. Recent studies suggested that Shh is often used by the same cell population to control different processes, including cell proliferation and migration, raising the possibility that Shh could contribute to these aspects of OPC development. In support of this idea, we show here that Shh induces the proliferation of OPCs derived from embryonic mouse ON explants and acts as a chemoattractant for their migration. In ovo injections of hybridomas secreting Shh-specific blocking antibody decreases the number of OPCs present in chick ONs, particularly in the retinal portion of the nerve. Altogether these data indicate that Shh contributes to OPC proliferation and distribution along the ON, in addition to their specification.