Generation of PTEN knockout bone marrow mesenchymal stem cell lines by CRISPR/Cas9-mediated genome editing

Area of Science:

• Stem cell biology
• Gene editing
• Tissue engineering

Background:

• The tumor suppressor PTEN regulates crucial cell functions including proliferation, differentiation, and apoptosis.
• Loss of PTEN in bone mesenchymal stem cells (BMSCs) affects their function in tissue repair.
• CRISPR/Cas9 gene editing offers a flexible method for precise genetic manipulation.

Purpose of the Study:

• To generate and characterize PTEN-knockout (PTEN-KO) bone mesenchymal stem cells (BMSCs) using CRISPR/Cas9.
• To investigate the impact of PTEN knockout on BMSC proliferation and multi-lineage differentiation potential.

Main Methods:

• PTEN gene knockout in MSCs using CRISPR/Cas9 system.
• Validation of PTEN knockout via PCR, Western blot, and sequencing.
• Assessment of cell proliferation using CCK-8 assay and Trypan blue staining.
• Evaluation of osteogenic and adipogenic differentiation using Alizarin red and Oil red staining, respectively.
• Analysis of differentiation marker gene expression (Id4, Runx2, ALP, PPARγ) via qPCR and immunocytochemistry.

Main Results:

• PTEN-KO MSCs exhibited significantly increased cell viability and survival compared to wild-type cells.
• Following osteogenic and adipogenic induction, PTEN-KO cells showed reduced expression of key differentiation markers (Runx2, PPARγ).
• Alizarin red and Oil red staining confirmed a decrease in osteogenic and adipogenic differentiation capacity in PTEN-KO cells.
• PTEN-KO cells demonstrated enhanced proliferation but diminished multi-directional differentiation potential.

Conclusions:

• PTEN knockout in BMSCs enhances proliferation but compromises their differentiation potential.
• The PTEN gene plays a critical role in maintaining the multi-lineage differentiation capacity of BMSCs.
• PTEN status can serve as a valuable indicator for assessing BMSC suitability in tissue engineering applications.