Expanded CD133⁺ Cells from Human Umbilical Cord Blood Improved Heart Function in Rats after Severe Myocardial...

Area of Science:

• Cardiovascular Research
• Regenerative Medicine
• Cell Therapy

Background:

• Pharmacological treatments for myocardial infarction have limited efficacy.
• Cell therapy, particularly using endothelial progenitor cells (EPCs), offers new therapeutic avenues for ischemic conditions.
• CD133+ cells are a promising source for EPC enrichment.

Purpose of the Study:

• To evaluate the therapeutic potential of purified and expanded human umbilical cord blood-derived CD133+ cells after acute myocardial infarction (AMI) in rats.
• To compare the efficacy of purified versus expanded CD133+ cells in promoting cardiac recovery and vascular regeneration.

Main Methods:

• Intramyocardial transplantation of purified or expanded CD133+ cells into infarcted rat hearts.
• Assessment of cardiac function using electrocardiogram (ECG).
• Histological analysis and fluorescence in situ hybridization (FISH) to evaluate neovascularization and cell engraftment.

Main Results:

• Expanded CD133+ cells exhibited an endothelial-like phenotype (CD31+, vWF+) after in vitro expansion.
• Rats receiving expanded CD133+ cells showed significantly improved cardiac contraction and reduced cardiac remodeling compared to those receiving purified cells.
• Both purified and expanded CD133+ cells promoted equivalent neovascularization in the infarcted myocardium.
• Limited detection of human cells at 28 days post-transplantation suggests paracrine mechanisms are key.

Conclusions:

• Expanded CD133+ cells are more effective than purified CD133+ cells in improving cardiac function and reducing adverse remodeling post-AMI.
• Both cell types facilitate vascular regeneration, but expanded CD133+ cells demonstrate superior therapeutic benefits.
• The therapeutic effects are likely mediated by paracrine signaling, highlighting expanded CD133+ cells as promising candidates for vascular regeneration therapies.