A comparative study on intra-articular versus systemic gene electrotransfer in experimental arthritis

Area of Science:

• Biotechnology
• Gene Therapy
• Immunology

Background:

• Electric pulse-mediated gene transfer, or electrotransfer (ET), is a successful in vivo technique for DNA delivery.
• Anti-inflammatory cytokine strategies are effective in experimental arthritis models.
• Investigating ET for non-viral gene transfer into arthritic joint tissue is crucial.

Purpose of the Study:

• To compare the therapeutic efficiency of local versus systemic delivery of interleukin-10 (IL-10) using in vivo ET for arthritis treatment.
• To evaluate the effectiveness of electrotransfer for gene delivery into arthritic joints.

Main Methods:

• A plasmid vector encoding IL-10 was delivered into DBA/1 mouse knee joints using ET.
• Kinetics of transgene expression were analyzed via ELISA in sera and knees.
• Therapeutic efficiency of intra-articular (i.a.) ET was compared to intra-muscular (i.m.) ET in a collagen-induced arthritis (CIA) mouse model.

Main Results:

• Local IL-10 secretion peaked at day 7 post-i.a. ET and decreased within 2 weeks.
• Intra-muscular ET of 25 microg of IL-10 significantly inhibited all clinical and biological features of arthritis.
• Intra-articular ET showed only mild improvement, even with weekly 100 microg doses.

Conclusions:

• Gene transfer into arthritic joints via ET is effective for delivering anti-inflammatory cytokines.
• Short transgene expression duration limits the therapeutic effect of i.a. ET for arthritis.
• Intra-muscular ET is more potent than i.a. ET for clinical benefit in CIA models.