Dataset Information

Use of an ETEC Proteome Microarray to Evaluate Cross-Reactivity of ETVAX^® Vaccine-Induced IgG Antibodies in Zambian Children.

ABSTRACT: Developing a broadly protective vaccine covering most ETEC variants has been elusive. The most clinically advanced candidate yet is an oral inactivated ETEC vaccine (ETVAX^®). We report on the use of a proteome microarray for the assessment of cross-reactivity of anti-ETVAX^® IgG antibodies against over 4000 ETEC antigens and proteins. We evaluated 40 (pre-and post-vaccination) plasma samples from 20 Zambian children aged 10-23 months that participated in a phase 1 trial investigating the safety, tolerability, and immunogenicity of ETVAX^® adjuvanted with dmLT. Pre-vaccination samples revealed high IgG responses to a variety of ETEC proteins including classical ETEC antigens (CFs and LT) and non-classical antigens. Post-vaccination reactivity to CFA/I, CS3, CS6, and LTB was stronger than baseline among the vaccinated compared to the placebo group. Interestingly, we noted significantly high post-vaccination responses to three non-vaccine ETEC proteins: CS4, CS14, and PCF071 (p = 0.043, p = 0.028, and p = 0.00039, respectively), suggestive of cross-reactive responses to CFA/I. However, similar responses were observed in the placebo group, indicating the need for larger studies. We conclude that the ETEC microarray is a useful tool for investigating antibody responses to numerous antigens, especially because it may not be practicable to include all antigens in a single vaccine.

SUBMITTER: Mubanga C

PROVIDER: S-EPMC10224314 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Use of an ETEC Proteome Microarray to Evaluate Cross-Reactivity of ETVAX® Vaccine-Induced IgG Antibodies in Zambian Children.

Mubanga Cynthia C Simuyandi Michelo M Mwape Kapambwe K Chibesa Kennedy K Chisenga Caroline C Chilyabanyama Obvious Nchimunya ON Randall Arlo A Liang Xiaowu X Glashoff Richard H RH Chilengi Roma R

Vaccines 20230504 5

Developing a broadly protective vaccine covering most ETEC variants has been elusive. The most clinically advanced candidate yet is an oral inactivated ETEC vaccine (ETVAX®). We report on the use of a proteome microarray for the assessment of cross-reactivity of anti-ETVAX® IgG antibodies against over 4000 ETEC antigens and proteins. We evaluated 40 (pre-and post-vaccination) plasma samples from 20 Zambian children aged 10-23 months that participated in a phase 1 trial inve ...[more]

PMID: 37243042

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Dataset Information

Use of an ETEC Proteome Microarray to Evaluate Cross-Reactivity of ETVAX^® Vaccine-Induced IgG Antibodies in Zambian Children.

Publications

Use of an ETEC Proteome Microarray to Evaluate Cross-Reactivity of ETVAX<sup>®</sup> Vaccine-Induced IgG Antibodies in Zambian Children.

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