Related Experiment Video
Updated: Jul 27, 2025
08:14
Direct Induction of Hemogenic Endothelium and Blood by Overexpression of Transcription Factors in Human Pluripotent Stem Cells
Published on: December 3, 2015
7.6K
Rapid activation of hematopoietic stem cells
Roshina Thapa1, Erez Elfassy2, Leonid Olender1
1The Shraga Segal Department of Microbiology, Immunology, and Genetics, Faculty of Health Sciences, National Institute for Biotechnology in the Negev, The Ben-Gurion University of the Negev, 84105, Beer Sheva, Israel.
Stem Cell Research & Therapy
|June 6, 2023
Summary
Hematopoietic stem cells (HSCs) rapidly activate within 2 hours of immune stimulation. This early response, marked by CD69 and CD317 expression, quickly moves HSCs out of quiescence.
Area of Science:
- Hematology
- Immunology
- Stem Cell Biology
Background:
- Adult hematopoietic stem cells (HSCs) reside in a quiescent state within the bone marrow (BM).
- HSCs can be activated by perturbations like infection or blood loss, but early activation stages are poorly understood.
Purpose of the Study:
- To investigate the earliest molecular events and kinetics of HSC activation following immune stimulation.
- To identify reliable surface markers indicative of rapid HSC activation.
Main Methods:
- Utilized surface markers CD69 and CD317 to track HSC activation.
- Applied viral-like (poly-Inosinic-poly-Cytidylic) and bacterial-like (Lipopolysaccharide) immune stimuli.
- Quantified dose-response relationships and marker expression dynamics.
Main Results:
- HSC activation was detected as early as 2 hours post-stimulation.
- Dynamic expression patterns of CD69 and CD317 varied with different immune stimuli.
- A low dose threshold and high sensitivity were observed for HSC and progenitor activation.
- Increased expression of activation markers correlated with an early exit from quiescence.
Conclusions:
- The response of adult stem cells to immune stimuli is rapid and highly sensitive.
- Immune challenges quickly induce HSCs to exit their quiescent state, initiating activation processes.
Related Concept Videos
01:01Regulation of Hematopoietic Stem Cells
3.2K
All blood and immune cells are produced from the multipotent hematopoietic stem cells (HSCs) by the process of hematopoiesis. However, they all have a limited life span. In addition, many are depleted in immune surveillance or combatting an injury or infection. This makes blood one of the most regenerative tissues. Hematopoiesis helps replenish these blood and immune cells, restoring the body's normal functioning. However, overproduction of blood and immune cells can make them cancerous or...
3.2K
01:19Multipotency of Hematopoietic Stem Cells
3.2K
The hematopoietic stem cells or HSCs are multipotent, meaning they can differentiate and give rise to all blood and immune cells. HSCs are maintained in the quiescent stage until an external stimulus initiates their differentiation. The multipotent HSCs exist as two heterogeneous populations, long-term repopulating cells (LTRC) and short-term repopulating cells (STRC). The two HSC populations have different surface markers or receptors and are classified based on quiescence and long-term...
3.2K
01:21Hematopoiesis
5.4K
The process of blood cell formation is called hematopoiesis. Hematopoiesis starts early during development, on the seventh day of embryogenesis. This phase of hematopoiesis is called the primitive wave, wherein the extraembryonic yolk sac allows the production of erythroid cells and endothelial cells from a common precursor called hemangioblast. The erythroid cells provide oxygen to support the growth of the rapidly dividing embryo. Hemangioblasts later develop into hematopoietic stem cells or...
5.4K
01:20Overview of Hematopoiesis
4.1K
Hematopoiesis, or blood cell production, is a vital biological process that begins early in embryonic development and continues throughout life. This process generates the various types of cells found in blood, including red blood cells, white blood cells, and platelets from hematopoietic stem cells (HSCs).
Developmental Phases of Hematopoiesis
Initially, HSCs are formed in the embryonic yolk sac, a critical site for early blood cell production. These stem cells subsequently migrate to other...
Developmental Phases of Hematopoiesis
Initially, HSCs are formed in the embryonic yolk sac, a critical site for early blood cell production. These stem cells subsequently migrate to other...
4.1K
01:34Production of Formed Elements
1.5K
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...
1.5K
01:28Role of Hematopoietic Growth Factors
1.4K
Hematopoietic growth factors are molecules that regulate the differentiation rate of hematopoietic stem cells (HSCs). Erythropoietin (EPO), primarily produced by the kidneys, plays a crucial role in erythrocyte production. When oxygen levels in the blood are low, EPO is released into the bloodstream, reaching the bone marrow, where it stimulates HSCs to differentiate and mature into erythrocytes, which are vital for oxygen transport.
Thrombopoietin (TPO), mainly released by the liver,...
Thrombopoietin (TPO), mainly released by the liver,...
1.4K