Explainers
Explained: How do monoclonal antibodies impact modern medicine?
Monoclonal antibodies are life-saving therapeutics that can be used for a myriad of conditions from infectious diseases to cancer.
Traditional drug modalities often fall short in targeting complex disease mechanisms with both precision and low toxicity. Monoclonal antibodies (mAbs) offer a flexible, specific platform that addresses these challenges. Innovations in mAb design are driving modern cancer therapies, improving diagnostics, and accelerating target validation for future drug discovery.
Download this Explainer Article to learn:
- How antibody engineering and bispecific design are expanding therapeutic targets
- The role of mAbs in intracellular targeting and immune modulation
- How mAbs are transforming biomarker discovery and personalized medicine
Top Image Credit:
iStock.com/nopparit
10 | DRUGDISCOVERYNEWS.COM MARCH 2025 DRUGDISCOVERYNEWS.COM MARCH 2025 | 11
Antibodies are the immune system’s precision-
guided missiles that recognize and neutralize
harmful invaders with high specificity.
These Y-shaped proteins, produced by B cells,
patrol the body in search of foreign molecules
or antigens to bind and eliminate (1). Their
specificity lies in the intricate architecture
of their antigen-binding sites, which interact
with unique molecular structures on antigens
called epitopes. Each antibody is composed
of two heavy chains and two light chains,
linked by disulfide bonds that provide stability
(1). These chains’ variable regions form the
fragment antigen-binding (Fab) region, where
specialized loops known as complementaritydetermining
regions (CDRs) create an exact
molecular fit with the target antigen (1,2).
The binding between an antibody and its
epitope is governed by an interplay of noncovalent
forces, including hydrogen bonding,
electrostatic interactions, and van der Waals
forces (3). Once an epitope locks into the Fab
region, subtle conformational changes, usually
in the Fab region but sometimes in the
epitope, further strengthen the bond, ensuring
a firm grip on the antigen.
In addition to target binding, the fragment
crystallizable (Fc) region at the antibody’s
stem plays a crucial role in immune signaling,
activating pathways such as antibodydependent
cellular cytotoxicity (ADCC) and
complement-dependent cytotoxicity (CDC)
(4). These processes recruit immune cells like
natural killer (NK) cells and macrophages to
destroy the marked pathogens or abnormal
cells (4). The Fc region binds to specific receptors
on immune cells, such as the Fcγ receptors
on NK cells and macrophages, which
then trigger these immune responses.
How do monoclonal
antibodies impact
modern medicine?
Monoclonal antibodies are life-saving therapeutics
that can be used for a myriad of conditions from
infectious diseases to cancer.
By MARNIE WILLMAN, PHD | Illustrations by KRISTYN REID
ANTIBODIES ARE HIGHLY SPECIALIZED PROTEINS THAT
recognize and neutralize threats with precision. Beyond their
natural immune function, scientists have engineered them
into powerful tools for targeting cancer, autoimmune diseases,
and infections. Advances in antibody-based therapies continue to
improve specificity, overcome biological barriers, and enable more precise
interventions. Ongoing research is refining these strategies, addressing
challenges in drug development, manufacturing, and clinical applications.
With innovations in protein engineering, bispecific antibodies, and targeted
delivery systems, antibody therapeutics are becoming increasingly
versatile and effective.
How do antibodies recognize their targets?
Antigen binding site
Antibody binding
Epitope
Disulfide
bonds
Heavy chain
Fab
Fc
region
Variable region
Complimentaritydetermining
region
Fc region of the
antibody binds to Fc
receptors on NK cells
and macrophages.
The epitope is
attracted to the
binding site of
the antibody.
Light chain
Target
cell
10 | DRUGDISCOVERYNEWS.COM MARCH 2025 DRUGDISCOVERYNEWS.COM MARCH 2025 | 11
Antibodies are the immune system’s precision-
guided missiles that recognize and neutralize
harmful invaders with high specificity.
These Y-shaped proteins, produced by B cells,
patrol the body in search of foreign molecules
or antigens to bind and eliminate (1). Their
specificity lies in the intricate architecture
of their antigen-binding sites, which interact
with unique molecular structures on antigens
called epitopes. Each antibody is composed
of two heavy chains and two light chains,
linked by disulfide bonds that provide stability
(1). These chains’ variable regions form the
fragment antigen-binding (Fab) region, where
specialized loops known as complementaritydetermining
regions (CDRs) create an exact
molecular fit with the target antigen (1,2).
The binding between an antibody and its
epitope is governed by an interplay of noncovalent
forces, including hydrogen bonding,
electrostatic interactions, and van der Waals
forces (3). Once an epitope locks into the Fab
region, subtle conformational changes, usually
in the Fab region but sometimes in the
epitope, further strengthen the bond, ensuring
a firm grip on the antigen.
In addition to target binding, the fragment
crystallizable (Fc) region at the antibody’s
stem plays a crucial role in immune signaling,
activating pathways such as antibodydependent
cellular cytotoxicity (ADCC) and
complement-dependent cytotoxicity (CDC)
(4). These processes recruit immune cells like
natural killer (NK) cells and macrophages to
destroy the marked pathogens or abnormal
cells (4). The Fc region binds to specific receptors
on immune cells, such as the Fcγ receptors
on NK cells and macrophages, which
then trigger these immune responses.
How do monoclonal
antibodies impact
modern medicine?
Monoclonal antibodies are life-saving therapeutics
that can be used for a myriad of conditions from
infectious diseases to cancer.
By MARNIE WILLMAN, PHD | Illustrations by KRISTYN REID
ANTIBODIES ARE HIGHLY SPECIALIZED PROTEINS THAT
recognize and neutralize threats with precision. Beyond their
natural immune function, scientists have engineered them
into powerful tools for targeting cancer, autoimmune diseases,
and infections. Advances in antibody-based therapies continue to
improve specificity, overcome biological barriers, and enable more precise
interventions. Ongoing research is refining these strategies, addressing
challenges in drug development, manufacturing, and clinical applications.
With innovations in protein engineering, bispecific antibodies, and targeted
delivery systems, antibody therapeutics are becoming increasingly
versatile and effective.
How do antibodies recognize their targets?
Antigen binding site
Antibody binding
Epitope
Disulfide
bonds
Heavy chain
Fab
Fc
region
Variable region
Complimentaritydetermining
region
Fc region of the
antibody binds to Fc
receptors on NK cells
and macrophages.
The epitope is
attracted to the
binding site of
the antibody.
Light chain
Target
cell
