Inflammation-induced transgene expression in genetically engineered equine mesenchymal stem cells

Area of Science:

• Regenerative Medicine
• Gene Therapy
• Osteoarthritis Research

Background:

• Osteoarthritis is a leading cause of disability with limited treatment options.
• Cell-based therapies, particularly using mesenchymal stem cells (MSCs), show promise for regenerative medicine.
• Targeted gene therapy could enhance MSC capabilities, requiring controllable transgene expression systems.

Purpose of the Study:

• To develop a system for inducible transgene expression in equine MSCs.
• To utilize a nuclear factor κB (NFκB)-responsive promoter regulated by inflammatory cytokines.
• To assess the feasibility of on-demand gene expression for potential osteoarthritis applications.

Main Methods:

• Equine bone marrow-derived MSCs were transduced with a lentiviral vector containing the luciferase gene under an NFκB-responsive promoter.
• Luciferase activity was measured in response to varying concentrations of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNFα).
• Inducibility was tested in both undifferentiated and chondrogenically differentiated MSCs.

Main Results:

• Cytokine stimulation (TNFα and IL-1β) dose-dependently increased luciferase expression in transduced MSCs.
• TNFα induced higher transgene expression than IL-1β.
• Transgene expression could be modulated on and off through repeated stimulation cycles, even in differentiated cells.

Conclusions:

• An NFκB-responsive promoter enables on-demand transgene expression in equine MSCs, controlled by inflammatory cytokines.
• This system allows for inducible gene expression in both undifferentiated and differentiated MSCs.
• The findings support the potential of this system for cell-based osteoarthritis therapies.