IMPROVED EFFICACY OF ANTI-AMYLOID SCFV BY MULTIMERIZATION AND INCREASED STABILITY
- YONA LEVITES, United States of America
Abstract
Aims
Search for effective therapies for Alzheimer’s Disease (AD) and related neurodegenerative diseases remains a significant unmet medical need, thus immunotherapeutic approaches such as single chain fragments have gained increasing interest as research tools and as pharmacological drugs in recent years, but they are limited by low expression efficiency, low binding affinity and short half life. To overcome these problems we generated a fusion protein comprising a specific anti-Aβ scFv and collagen domain of a C1QTNF protein (CD).
Methods
Anti-Aβ recombinant scFvs fused to CD were packaged in AAV and delivered to newborn CRND8 mice as well as stereotaxically injected into the hippocampus of adult CRND8 mice with preexisting pathology. Amyloid burden and Aβ levels in the soluble, SDS soluble and SDS-insoluble, Formic Acid soluble fractions were compared between various cohorts. Non –specific scFv-CD as well as CD alone served as controls.
Results
We have cloned several anti-Aβ scFv (fibril-specific, anti-Aβ42, or pan-Aβ) fused CD. We then characterized scFv-CD compared wth scFv alone in vivo. Further we tested disease-modifying potential of new scFv-CD in CRND8 mice in a prevention as well as therapeutic paradigm. ScFv-CD was more efficacious in preventing formation of amyloid plaques. Further assessment whether efficacy can be improved by functionalizing scFv-CDs is underway.
Conclusions
CD fusion increases stability and half life of scFv, while retaining its binding properties. Moreover, multimerization may increase the functional affinity of the binding domain of scFvs. Thus, our studies provide a framework for identifying an optimized immunotherapy for AD, and potentially other neurodegenerative disorders.