Injection of Affibodies by a Self-Organizing Bacterial Syringe to Interfere with Intracellular Signaling

Area of Science:

• Microbiology and Molecular Biology
• Cellular Biology
• Biotechnology

Background:

• Photorhabdus luminescens utilizes a toxin complex for cellular invasion.
• Targeting intracellular signaling pathways remains a challenge in cell biology and therapeutics.

Purpose of the Study:

• To engineer the Photorhabdus toxin complex (PTC) for the delivery of foreign proteins into mammalian cells.
• To demonstrate the potential of this system for therapeutic intervention by inhibiting cancer cell proliferation.

Main Methods:

• Recombinant expression and engineering of the Photorhabdus toxin complex (PTC).
• Development of trimeric affibodies as cargo proteins.
• Application of the engineered PTC system for protein translocation across cellular membranes in mammalian cells.
• Inhibition of Ras-driven tumor cell proliferation using an affibody targeting Raf kinase.

Main Results:

• Successful engineering of the recombinant Photorhabdus toxin complex (PTC) for cargo protein translocation.
• Demonstrated efficient injection of trimeric affibodies into mammalian cells.
• Proof-of-principle inhibition of Ras-driven tumor cell proliferation via targeted affibody delivery.

Conclusions:

• The engineered Photorhabdus toxin complex (PTC) system provides a novel platform for delivering functional proteins into cells.
• This technology has broad applicability for targeting diverse signaling molecules in cell biology and therapeutic strategies.
• Potential for developing new treatments for diseases driven by specific signaling pathways.