Related Experiment Video
Updated: Aug 5, 2026
A Protein Microarray Assay for Serological Determination of Antigen-specific Antibody Responses Following Clostridium difficile Infection
Published on: June 15, 2018
Isolation of Monoclonal Neutralizing Single-Domain Antibodies Against Clostridioides difficile Toxin B
I A Alekseeva1, A S Ungur1, I A Favorskaya1
1Gamaleya National Research Center of Epidemiology and Microbiology of the Ministry of Health of the Russian Federation, Moscow, 123098 Russia.
Abstract:
The Clostridioides difficile infection (CDI) is one of the most common nosocomial infections around. The key pathogenicity factors of this bacterium include the toxins A and B that cause the disease symptoms. Neutralization of these toxins is one of the promising strategies for CDI treatment. Here, we isolated a panel of single-domain antibodies to the toxin B CROPs domain. Two antibodies, TB5A7 and TB4A8, exhibiting potent neutralizing activity were modified to produce homodimeric forms. The TB5A7 and TB4A8 dimers were characterized by enhanced neutralizing activity and protected animals from a toxin B lethal challenge. The obtained antibodies may be used to develop new agents for CDI treatment.
Insights
Researchers developed homodimeric antibodies targeting Clostridioides difficile toxin B. These enhanced antibodies neutralize the toxin effectively and protect against lethal challenges, offering a promising new strategy for treating C. difficile infections (CDI).
Area of Science:
- Microbiology
- Immunology
- Pharmacology
Background:
- Clostridioides difficile infection (CDI) is a prevalent nosocomial infection.
- Toxins A and B are key virulence factors contributing to CDI pathogenesis.
- Neutralizing these toxins presents a viable therapeutic strategy for CDI.
Purpose of the Study:
- To isolate and characterize single-domain antibodies targeting Clostridioides difficile toxin B.
- To enhance the neutralizing efficacy of these antibodies through homodimerization.
- To evaluate the therapeutic potential of these engineered antibodies in preclinical models.
Main Methods:
- Isolation of single-domain antibodies against the Clostridioides difficile toxin B CROPs domain.
- Engineering of homodimeric forms of potent neutralizing antibodies (TB5A7 and TB4A8).
- In vitro neutralization assays and in vivo protection studies against toxin B challenge.
Main Results:
- Identification of two effective single-domain antibodies, TB5A7 and TB4A8.
- Homodimeric forms of TB5A7 and TB4A8 demonstrated significantly enhanced neutralizing activity.
- The antibody dimers provided protection in animals challenged with a lethal dose of toxin B.
Conclusions:
- Engineered homodimeric antibodies targeting Clostridioides difficile toxin B exhibit superior neutralizing potency.
- These enhanced antibodies represent a promising therapeutic candidate for the development of novel agents against CDI.
- Further development of these antibody-based therapies could lead to effective treatments for C. difficile infections.
