Are endothelial outgrowth cells a potential source for future re-vascularization therapy?

Area of Science:

• Cell Biology
• Regenerative Medicine
• Vascular Biology

Background:

• Endothelial progenitor cells (EPCs), including endothelial outgrowth cells (EOCs), are crucial for repairing blood vessels after ischemic events.
• In vitro expansion is necessary for therapeutic applications due to low circulating cell numbers, but potential aging effects are a concern.

Purpose of the Study:

• To investigate morphological and functional changes in human umbilical cord blood-derived EOCs during in vitro expansion (aging).
• To evaluate the impact of long-term culture on EOCs' potential for therapeutic use in vasculogenesis.

Main Methods:

• Isolation and culture of EOCs from human umbilical cord blood using two distinct purification methods.
• Assessment of EOCs over time using flow cytometry, growth assays, tube formation assays, and beta-galactosidase activity measurement.

Main Results:

• EOCs exhibited altered morphology, becoming larger and more granular with decreased growth rates over time.
• Late-passage EOCs showed increased beta-galactosidase expression, indicating senescence, and reduced ability to form tubes.

Conclusions:

• Long-term in vitro expansion leads to senescence in EOCs, compromising their functionality and therapeutic potential.
• Optimizing cell harvest timing is essential to ensure the use of functional EOCs for regenerative therapies.
• Local injection of EOCs may reduce the need for extensive in vitro expansion, preserving therapeutic efficacy.