Murine and human very small embryonic-like cells: a perspective

Area of Science:

• Stem cell biology
• Developmental biology
• Hematology

Background:

• Very small embryonic-like (VSEL) stem cells were identified in murine bone marrow (mBM) and human umbilical cord blood (hUCB) in 2006.
• Murine VSEL cells have been linked to mesenchymal stem cells (MSCs), suggesting a potential overlap.
• The pluripotency of VSEL cells remains a subject of debate, particularly regarding human populations.

Purpose of the Study:

• To critically re-examine the evidence supporting stemness and pluripotency in both murine and human VSEL cells.
• To compare the characteristics of VSEL cells from murine and human sources.
• To investigate the in vitro behavior and properties of human VSEL cells.

Main Methods:

• Comparative analysis of existing data on murine and human VSEL cells.
• In vitro culture and characterization of human VSEL cell populations.
• Re-evaluation of evidence for pluripotency and stem cell markers.

Main Results:

• Murine VSEL cells show overlap with neural crest-derived MSCs.
• Human VSEL cells demonstrated minimal similarity to murine VSEL cells.
• Human VSEL cells were found to be inactive, unable to expand in vitro, and lacked embryonic or adult stem cell properties.

Conclusions:

• The concept of embryonic-like stem cells in murine bone marrow may be influenced by the presence of mesenchymal precursors.
• Human VSEL cells do not exhibit stem cell characteristics and appear to be an aberrant population.
• Further research is needed to clarify the nature and potential of VSEL cells in different species.