Corynebacterium diphtheriae DT Specific Neutra™ Antibody Products

Are you grappling with prolonged drug development timelines, inconsistent toxin neutralization assays, or antibody specificity hurdles? Creative Biolabs’ C. diphtheriae DT specific Neutra™ antibody products leverage advanced epitope mapping and high-affinity recombinant antibody engineering to streamline toxin research, therapeutic discovery, and vaccine validation.

Introduction to C. diphtheriae DT

Corynebacterium diphtheriae DT (C. diphtheriae DT) is an exotoxin secreted by lysogenized strains of Corynebacterium diphtheriae. This 58-kDa protein consists of two domains: the catalytic A subunit (DT-A) and the receptor-binding B subunit (DT-B). DT disrupts host cell protein synthesis by ADP-ribosylating elongation factor 2, leading to cell death. Its extreme potency—with a lethal dose as low as 100 ng/kg—underscores its significance in bacterial pathogenesis and therapeutic targeting.

• Structural Insights

The tertiary structure of DT is defined by three functional regions. The N-terminal catalytic domain executes enzymatic toxicity. The central transmembrane domain facilitates toxin entry into endosomes, while the C-terminal receptor-binding domain mediates host cell attachment via heparin-binding epidermal growth factor-like growth factor (HBEGF). Structural studies reveal that DT-B forms a beta-sandwich fold critical for receptor recognition, while DT-A adopts a mixed alpha-beta topology optimized for intracellular delivery.

Fig.1 Schematic representation of diphtheria toxin.¹

• Related Signaling Pathways

DT binding to HBEGF triggers clathrin-mediated endocytosis. Acidification within endosomes induces conformational rearrangements in DT, enabling pore formation and translocation of DT-A into the cytosol. This process activates stress pathways such as MAPK/ERK and p38, culminating in apoptosis. Additionally, DT-induced ADP-ribosylation disrupts ribosomal function, activating unfolded protein response (UPR) pathways and endoplasmic reticulum (ER) stress.

Fig.2 Interaction of DT with its receptor, followed by its internalization.¹

• Associated Pathologies

C. diphtheriae DT is the primary virulence factor responsible for diphtheria, a life-threatening respiratory infection characterized by pseudomembrane formation in the upper airways. Systemic toxin dissemination causes myocarditis, neuropathy, and nephritis, with mortality rates up to 20% in untreated cases. Despite widespread vaccination, emerging non-toxigenic strains and waning herd immunity underscore the need for advanced therapeutic countermeasures.

Applications of C. diphtheriae DT Neutralizing Antibodies

• Clinical Diagnostics and Toxin Detection

DT-neutralizing antibodies enable rapid, sensitive detection of toxin in clinical samples. Sandwich ELISA formats utilizing DT-B-specific mAbs are critical for diagnosing diphtheria in endemic regions, while epitope-specific antibodies differentiate toxigenic from non-toxigenic strains.

• Therapeutic Development and Passive Immunization

Monoclonal antibody cocktails targeting multiple DT epitopes are being evaluated as adjuncts to diphtheria antitoxin (DAT) in neutralizing systemic toxin. Preclinical data demonstrate that dual-target mAbs reduce mortality in animal models by synergistically inhibiting receptor binding and enzymatic activity.

• Vaccine Potency Testing

Quantifying anti-DT antibody titers is essential for assessing vaccine efficacy. Toxin neutralization assays using standardized DT-specific antibodies provide reproducible metrics for evaluating immune responses in vaccinated populations, aiding in booster schedule optimization.

• Mechanistic Studies of Toxin Entry

Neutralizing antibodies serve as molecular tools to dissect DT internalization pathways. For instance, anti-DT-B antibodies labeled with fluorophores or gold nanoparticles enable real-time visualization of toxin-receptor interactions via live-cell imaging or electron microscopy.

• Antiviral and Antitoxin Drug Screening

High-throughput screening platforms incorporating DT-neutralizing antibodies identify small molecules that disrupt toxin-receptor binding or intracellular trafficking. These assays accelerate the discovery of toxin inhibitors with therapeutic potential.

Our Anti-C. diphtheriae DT Antibodies

Neutralizing antibodies targeting DT are indispensable for both diagnostic and therapeutic applications. High-affinity monoclonal antibodies (mAbs) against DT-B block receptor binding, while those targeting DT-A inhibit catalytic activity. Creative Biolabs' DT-specific Neutra™ antibodies are engineered using phage display libraries and validated via in vitro toxin neutralization assays (TNA) and in vivo challenge models. These reagents exhibit sub-nanomolar affinity, cross-reactivity with toxin variants, and robust performance in ELISA, Western blot, and neutralization assays.

Creative Biolabs offers C. diphtheriae DT specific Neutra™ antibody products that are engineered to meet the highest standards of specificity, affinity, and reproducibility. Whether your focus is toxin neutralization, vaccine development, or mechanistic research, our antibody solutions empower your scientific objectives. Contact our team today to discuss customized antibody development tailored to your project.

REFERENCE

1. Shafiee, Fatemeh, Marc G. Aucoin, and Ali Jahanian-Najafabadi. "Targeted diphtheria toxin-based therapy: a review article." Frontiers in microbiology 10 (2019): 2340. Distributed under Open Access license CC BY 4.0, without modification. https://doi.org/10.3389/fmicb.2019.02340