What is the clinical evidence from this study?

Study design: Other. Population: Coxsackievirus A5 (CVA5) infection. Intervention: Monoclonal antibodies against CVA5. Primary outcome: Identification of key amino acids for conformational neutralizing epitopes.

What question did this study set out to answer?

This research aims to identify the key amino acids that define conformational neutralizing epitopes of coxsackievirus A5 (CVA5).

May 3, 2026Open Access

Identification of key amino acids defining conformational neutralizing epitopes of coxsackievirus A5 using monoclonal antibody escape mutants

Key Result

Ten key amino acid sites on the coxsackievirus A5 capsid were confirmed to be pivotal for monoclonal antibody recognition and neutralization, providing a structural framework for vaccine development.

Key Points

This research aims to identify the key amino acids that define conformational neutralizing epitopes of coxsackievirus A5 (CVA5).
Purified and characterized two IgG, one IgA, and five IgM neutralizing monoclonal antibodies (mAbs) for binding and neutralization potency.
Applied antibody pressure selection to generate immune escape mutants and conducted comparative sequence analysis with wild-type virus.
Used reverse genetics and structural mapping to confirm and localize critical residues on the viral capsid.
Identified ten key amino acid sites crucial for mAb recognition on CVA5: K1103, V1215, N1282, F1288, T1291, K2076, E2160, T3059, D3060, E3139.
Mapped these sites distinctly on the viral capsid: several at the southern rim, K1103 at the northern rim, and E3139 near the two-fold axis.
Provided the first evidence of multiple conformational neutralizing epitopes on CVA5, paving the way for vaccine development.

Structured PICO

Population

Coxsackievirus A5 (CVA5) and monoclonal antibodies (2 IgG, 1 IgA, and 5 IgM)

Intervention

Antibody pressure selection and reverse genetics

Comparator

Wild-type virus

Outcome

Identification of key amino acids pivotal for mAb recognitionsurrogate

This study maps the conformational neutralizing epitopes of CVA5, providing a structural framework for vaccine and therapeutic development.

Limitations

Structural predictions are derived solely from computational models and lack experimental validation by cryo-EM.
Direct binding assays were not performed due to the difficulty of obtaining sufficient purified mutant virions.
In vivo efficacy of selected antibodies or epitope-based immunogens was not evaluated.
Moderate purity of the IgM antibodies.

Abstract

Background Coxsackievirus A5 (CVA5) is an emerging pathogen associated with severe hand, foot, and mouth disease. Protective antibodies are critical for protection from CVA5 infection, yet the antigenic determinants of CVA5 remain poorly defined. In this study, we aimed to map the conformational neutralizing epitopes of CVA5 using monoclonal antibodies (mAbs) and escape mutant analysis. Methods Two IgG, one IgA, and five IgM neutralizing mAbs were purified and characterized for binding affinity and neutralization potency. Antibody pressure selection was applied to generate immune escape mutants, and comparative sequence analysis with wild-type virus identified potential critical residues. Reverse genetics was used to confirm key sites pivotal for mAb recognition. Structural mapping was performed to localize these sites on the viral capsid. Results Ten key sites (K1103, V1215, N1282, F1288, T1291, K2076, E2160, T3059, D3060, E3139) were confirmed to be pivotal for mAb recognition. Structural mapping revealed distinct localization of these sites on the viral capsid: V1215, N1282, F1288, T1291, K2076, E2160, T3059, D3060 at the southern rim; K1103 at the canyon’s northern rim; and E3139 near the two-fold axis. Conclusion This study provides the first evidence of multiple conformational neutralizing epitopes on CVA5. These findings define the antigenic basis of CVA5 neutralization and offer a structural framework for vaccine and antibody-based therapeutic development.

اسأل الذكاء الاصطناعي

Bookmark

View Full Paper