Evaluating Interaction of Cord Blood Hematopoietic Stem/Progenitor Cells with Functionally Integrated...

Area of Science:

• * Stem Cell Biology
• * Regenerative Medicine
• * Hematopoiesis

Background:

• * Current ex vivo expansion of cord blood-derived hematopoietic stem/progenitor cells (CB-HSPC) faces challenges in achieving sufficient cell numbers for adult transplantation.
• * Two-dimensional (2D) cultures lead to a decrease in the percentage of primitive stem cells over time.

Purpose of the Study:

• * To investigate the efficacy of bioengineered three-dimensional (3D) liver constructs as surrogate fetal liver environments for ex vivo expansion of CB-HSPC.
• * To compare the maintenance of primitive HSPC in 3D-ECM scaffolds with cellular components versus 2D cultures.

Main Methods:

• * Creation of bioengineered 3D-liver-extracellular-matrix (3D-ECM) constructs seeded with hepatoblasts, fetal liver-derived (LvSt), or bone marrow-derived stromal cells.
• * Comparison of 3D constructs with respective 2D culture counterparts.
• * Assessment of HSPC viability, primitive subpopulation maintenance (flow cytometry, colony forming assays), and differentiation potential.

Main Results:

• * Cellular components within 3D-ECM scaffolds were essential for maintaining HSPC viability.
• * 3D-ECM structures, regardless of the microenvironment, preserved a higher percentage of primitive HSPC compared to 2D cultures.
• * Fetal liver-derived stromal cells (LvSt) in 3D-ECM provided the optimal balance between preserving primitive CB-HSPC and promoting cellular differentiation.

Conclusions:

• * Bioengineered 3D liver constructs, particularly those incorporating fetal liver stromal cells, offer a promising approach for ex vivo expansion of CB-HSPC.
• * This strategy can maintain the critical primitive stem cell population, addressing a key limitation in current expansion methods.
• * The findings suggest potential for generating sufficient CB-HSPC for adolescent and adult transplantation.