Video Experimental Relacionado
Updated: Aug 7, 2026

08:14
Direct Induction of Hemogenic Endothelium and Blood by Overexpression of Transcription Factors in Human Pluripotent Stem Cells
Published on: December 3, 2015
La hematopoyesis definitiva es iniciada de forma autónoma por la región AGM
1National Institute for Medical Research, London, United Kingdom.
Cell
|September 20, 1996
Resumen
Las células madre hematopoyéticas (HSC) son cruciales para el desarrollo de la sangre de los mamíferos. Este estudio identifica la región aorta-gonada-mesonefros (AGM) como la fuente embrionaria exclusiva de HSC definitivos, aclarando su origen.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- La hematopoyesis es la hematopoyesis.
- La investigación con células madre.
Sus antecedentes:
- El origen y el desarrollo temprano de las células madre hematopoyéticas de mamíferos (HSC) durante la embriogénesis no se entienden completamente.
- La actividad hematopoyética se produce en el saco vitelino y en la región aorta-gonada-mesonefros (AGM) antes de la colonización del hígado, pero se debaten sus respectivos roles en la generación de HSC.
Objetivo del estudio:
- Determinar el origen embrionario y el lugar de la generación inicial de células madre hematopoyéticas definitivas.
- Investigar el potencial para la expansión in vitro de las células madre hematopoyéticas embrionarias.
Principales métodos:
- Se empleó un nuevo sistema de cultivo de órganos in vitro para estudiar tejidos embrionarios.
- La región aorta-gonadas-mesonefros (AGM) y el saco vitelino del día 10 de gestación de embriones de ratón fueron cultivados.
- Se evaluó la generación y expansión de células madre hematopoyéticas dentro de estos tejidos cultivados.
Principales resultados:
- Se observó que las células madre hematopoyéticas inician de manera autónoma y exclusiva dentro de la región aorta-gonadas-mesonefrosis (AGM) en el día 10 de la gestación.
- Se obtuvo evidencia de la expansión in vitro de células madre hematopoyéticas dentro de la región AGM cultivada.
- La contribución del saco de la yema a la generación definitiva de HSC no fue respaldada por estos hallazgos.
Conclusiones:
- La región aorta-gonadas-mesonefros (AGM) se identifica como la fuente embrionaria primaria de células madre hematopoyéticas definitivas.
- Estos hallazgos indican que la región AGM siembra el hígado, estableciendo el sistema hematopoyético adulto definitivo.
- El estudio proporciona información crítica sobre los orígenes del desarrollo temprano del sistema hematopoyético de los mamíferos.
Videos de Conceptos Relacionados
Lineage Commitment
Commitment is the process whereby stem cells:
Production of Formed Elements
Hemangioblasts are multipotent stem cells originating from the mesoderm. They give rise to hematopoietic stem cells (HSCs), which undergo hematopoiesis to produce all the formed elements of blood. This process is regulated by a complex network of hematopoietic growth factors, including transcription factors, growth factors, and cytokines. These factors stimulate the HSCs to divide and differentiate, though some HSCs remain undifferentiated to maintain a self-renewing pool.
Most HSCs commit to...
Most HSCs commit to...
Vascular Spasm
The vascular phase, also known as vasospasm, is the initial stage of hemostasis, crucial for preventing excessive bleeding when a blood vessel is injured. After a vessel is cut, nerves in the damaged area trigger pain and other sensory impulses. Simultaneously, the smooth muscles in the vessel wall contract, resulting in a vascular spasm. This contraction reduces the vessel's diameter at the injury site, slowing or stopping blood loss through the vessel wall. Vascular spasms typically last for...
Formation of the Platelet Plug
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
Autoregulation of Blood Flow
Autoregulation mechanisms are characterized by their inherent capacity for self-regulation without necessitating specific nervous stimulation or endocrine control. These mechanisms facilitate the adjustment of blood flow and, therefore, perfusion specific to each tissue region. This self-regulation encompasses chemical signals and myogenic controls.
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Development of Blood Vessels
The development of the vascular system in a fetus is a complex and intricate process that begins as early as 15 to 16 days post-conception. This process starts outside the embryo, specifically in the mesoderm of the yolk sac, chorion, and connecting stalk. Approximately two days later, the formation of blood vessels occurs within the embryo itself.
The initial formation of this system is facilitated by the small amount of yolk present in the ovum and yolk sac. Blood vessels originate from...
The initial formation of this system is facilitated by the small amount of yolk present in the ovum and yolk sac. Blood vessels originate from...

