AXL-Receptor Targeted 14FN3 Based Single Domain Proteins (Pronectins™) from 3 Synthetic Human Libraries as Components...

Area of Science:

• Biotechnology
• Protein Engineering
• Cancer Therapeutics

Background:

• The AXL receptor is a key target in cancer therapy.
• Developing highly specific protein binders is crucial for targeted drug delivery.
• Non-immunogenic scaffolds are preferred to minimize adverse reactions.

Purpose of the Study:

• To isolate and characterize novel, highly specific protein binders targeting the AXL receptor.
• To develop a new class of bispecific T cell engager for cancer treatment.
• To evaluate the anti-tumor activity of AXL-targeted proteins.

Main Methods:

• Utilized synthetic libraries based on the 14th domain of Fibronectin III (14FN3) scaffold.
• Employed phage and yeast display techniques for protein binder selection.
• Conducted FACS analysis and in vitro cell-based assays to assess specificity and efficacy.

Main Results:

• Isolated 59 AXL receptor-targeted Pronectins™ with high affinity (KD 2-100 nM).
• Identified AXL54 as a lead candidate with exquisite AXL receptor specificity.
• Developed the first bispecific T cell engager (AXL54-linker-scFV CD3) for anti-tumor testing.

Conclusions:

• Pronectins™ represent a promising new class of AXL-targeted protein binders.
• AXL54 demonstrates significant potential for targeted cancer therapy.
• The developed bispecific T cell engager warrants further in vitro and in vivo investigation for anti-tumor efficacy.