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Updated: Jul 18, 2026
07:14
A Culture Method to Maintain Quiescent Human Hematopoietic Stem Cells
Published on: May 17, 2021
Chromatin-modifying agents permit human hematopoietic stem cells to undergo multiple cell divisions while retaining
Hiroto Araki1, Kazumi Yoshinaga, Piernicola Boccuni
1Section of Hematology/Oncology, Department of Medicine, University of Illinois at Chicago, 909 S. Wolcott Avenue, Chicago, IL 60612, USA.
Blood
|December 23, 2006
Summary
Chromatin-modifying agents 5-aza-2'-deoxycytidine (5azaD) and trichostatin A (TSA) can reverse the loss of function in human hematopoietic stem cells (HSCs) during in vitro expansion. Treated HSCs retain their marrow repopulating potential after cell division.
Area of Science:
- Stem cell biology
- Epigenetics
- Hematopoiesis
Background:
- Human hematopoietic stem cells (HSCs) lose functional properties upon cytokine-induced proliferation in vitro.
- This loss is presumed to result from the silencing of a critical HSC genetic program.
Purpose of the Study:
- To investigate if chromatin-modifying agents can reverse the silencing of the HSC genetic program.
- To determine if treated HSCs can retain their functional properties after in vitro expansion.
Main Methods:
- Sequential treatment of human cord blood CD34(+) cells with 5-aza-2 -deoxycytidine (5azaD) and trichostatin A (TSA).
- In vitro culture with cytokines and subsequent transplantation into immunodeficient mice.
- Analysis of cell division rates, marrow repopulating potential, and gene expression.
Main Results:
- 5azaD/TSA treated cells exhibited reduced proliferation compared to cytokine-only treated cells but retained marrow repopulating potential after 5-10 divisions.
- CD34(+)CD90(+) cells treated with 5azaD/TSA maintained their ability to repopulate marrow in immunodeficient mice.
- Expression of key self-renewal genes was upregulated in 5azaD/TSA treated cells.
Conclusions:
- Sequential treatment with 5azaD and TSA can preserve the functional properties of human HSCs during in vitro expansion.
- Chromatin modification offers a potential strategy to maintain HSC marrow repopulating potential for therapeutic applications.
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