High-level sustained transgene expression in human embryonic stem cells using lentiviral vectors

Area of Science:

• * Stem Cell Biology
• * Gene Therapy
• * Molecular Biology

Background:

• * Lentiviral vectors are utilized for gene delivery into human embryonic stem cells (hESCs).
• * Achieving sustained transgene expression in hESCs is critical for various research and therapeutic applications.
• * Optimizing vector design is essential for efficient and stable gene integration and expression.

Purpose of the Study:

• * To describe sustained transgene expression in hESCs using self-inactivating lentiviral vectors.
• * To evaluate the impact of vector modifications (SAR, insulator) on transgene expression levels and variability.
• * To assess transgene expression stability during differentiation of hESCs into hematopoietic precursors.

Main Methods:

• * Transduction of hESCs with vesicular stomatitis virus-pseudotyped lentiviral vectors encoding green fluorescent protein (GFP).
• * Incorporation of scaffold attachment region (SAR) and a chromatin insulator into the vector backbone.
• * Differentiation of transduced hESCs into CD34(+) hematopoietic precursors in vitro.
• * Monitoring of GFP expression over 60 days and during differentiation.

Main Results:

• * High-efficiency transduction of hESCs with lentiviral vectors, resulting in sustained GFP expression for over 60 days.
• * SAR incorporation increased average GFP expression, while SAR plus insulator reduced expression variability.
• * GFP expression was maintained with minimal silencing during differentiation into CD34(+) cells.

Conclusions:

• * Self-inactivating lentiviral vectors enable efficient and sustained transgene expression in hESCs.
• * Vector engineering with SAR and insulators can optimize transgene expression characteristics.
• * Stable transgene expression in hESCs has significant implications for gain-of-function studies and regenerative medicine.