Fc γ receptor compositional heterogeneity: Considerations for immunotherapy development

Area of Science:

• Immunology
• Molecular Biology
• Therapeutic Antibody Engineering

Background:

• Fcγ receptors (FcγRs) mediate cellular responses to antibody-bound targets, playing a key role in therapeutic monoclonal antibody (mAb) efficacy.
• Despite their importance, FcγR development lags behind antibody engineering, hindering optimization of immune responses.
• FcγRs exhibit significant heterogeneity due to genetic variations, isoforms, and post-translational modifications, complicating their study and engineering.

Purpose of the Study:

• To review the composition of endogenous FcγRs found on human leukocytes.
• To summarize recent advancements in engineering FcγRs for improved therapeutic applications.
• To identify potential FcγR features that could enhance clinical function and accelerate development of new therapies.

Main Methods:

• Analysis of FcγR composition from primary human leukocytes.
• Review of current literature on FcγR engineering strategies.
• Identification of key FcγR structural and functional elements for targeted modification.

Main Results:

• FcγRs are highly heterogeneous, with diverse alleles, forms (membrane-tethered, soluble), and glycosylation patterns.
• Engineered cell-based immunotherapies offer a platform for introducing modified FcγRs into clinical settings.
• A fundamental lack of knowledge regarding endogenous FcγR forms limits current improvement efforts.

Conclusions:

• Understanding the endogenous FcγR landscape is critical for rational engineering.
• Targeted engineering of FcγRs holds promise for developing more effective immunotherapies.
• Further research into FcγR biology can accelerate treatments for immune-related diseases.