Conformational Fingerprinting Using Monoclonal Antibodies (on the Example of Angiotensin I-Converting Enzyme-ACE)

Area of Science:

• Biochemistry
• Immunology
• Molecular Biology

Background:

• Over 30 years, 40+ monoclonal antibodies (mAbs) were generated against human and animal angiotensin-converting enzyme (ACE).
• These mAbs were utilized for ACE detection and quantification via ELISA, Western blotting, flow cytometry, and immunohistochemistry, typically using single antibodies.

Purpose of the Study:

• To explore novel insights into ACE structure and function by employing the entire collection of mAbs targeting diverse epitopes.
• To establish a new methodology termed 'conformational fingerprinting of ACE' for enhanced ACE characterization.

Main Methods:

• Epitope mapping of all generated mAbs against ACE, with a focus on conformational epitopes.
• Utilizing the complete set of mAbs to investigate ACE conformational changes, mutations, and tissue-specific characteristics.
• Application of mAbs for potential organ-specific drug/gene delivery, particularly targeting lung capillaries.

Main Results:

• Demonstrated that certain mAbs are highly sensitive to local conformational changes on the ACE surface.
• Successfully detected, localized, and characterized human ACE mutations.
• Established the concept of 'conformational fingerprinting of ACE', providing evidence for tissue-specific ACE variants.

Conclusions:

• The comprehensive use of mAbs provides a powerful tool for studying ACE structure, function, and mutations.
• Conformational fingerprinting of ACE offers promising scientific and diagnostic perspectives, including tissue-specific ACE identification.
• This mAb-based concept holds potential applicability for characterizing other glycoproteins.