Gut Microbiota, the Potential Key to Modulating Humoral Immunogenicity of New Platform COVID-19 Vaccines

Study Overview
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Brief Summary
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Vaccination is the best way to mitigate the coronavirus disease 2019 (COVID-19) pandemic, but the vaccine immunogenicity may be quite variable from person to person. There is increasing evidence suggesting that the gut microbiome is a major determinant of vaccine immunogenicity. Thus, the investigators investigated the relationship between gut microbiota and humoral immune response after COVID-19 vaccination.

Official Title
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Gut Microbiota, the Potential Key to Modulating Humoral Immunogenicity of New Platform COVID-19 Vaccines: Adenovirus-vectored Vaccine Versus mRNA Vaccine

Conditions
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Microbiome, Vaccine, Covid-19, SARS-CoV-2, Immunogenicity

Intervention / Treatment
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* Other: This is observational study


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: People assigned to get either BNT162b2 or ChAdOx1 vaccines informed concents Exclusion Criteria: Participants were excluded if they had a history of medication which would affect gut microbiota in the past 1 month, including antibiotics, laxatives, and motility drugs.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ChAdOx1 vaccinated group<br>From Febrary 25, 2021 to July 16, 2021, healthy healthcare workers were prospectively recruited at a tertiary hospital in Seoul, Republic of Korea, and they were assigned to get ChAdOx1 (Oxford/AstraZeneca) (n=26) vaccines. Participants were excluded if they had history of medication which would affect gut microbiota in the past 1 month, including antibiotics, laxatives, and motility drugs; previous history of positive SARS-CoV-2 test on nasopharyngeal PCR; or positive serum Spike IgG results. | Other: This is observational study<br>* We enrolled the healthcare workers assigned to get either BNT162b2 or ChAdOx1 by the Korean government.<br>|
| BNT162b2 vaccinated group<br>From Febrary 25, 2021 to July 16, 2021, 53 healthy healthcare workers were prospectively recruited at a tertiary hospital in Seoul, Republic of Korea, and they were assigned to get BNT162b2 (n=27) vaccines. Participants were excluded if they had history of medication which would affect gut microbiota in the past 1 month, including antibiotics, laxatives, and motility drugs; previous history of positive SARS-CoV-2 test on nasopharyngeal PCR; or positive serum Spike IgG results. | Other: This is observational study<br>* We enrolled the healthcare workers assigned to get either BNT162b2 or ChAdOx1 by the Korean government.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Taxonomic biomarkers predicting immune responses | This study aimed to analyze whether fecal microbiota composition before vaccination was associated with immmune response level | before the administration of first-dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Antibody titres after the first dose vaccination | This study aimed to analyze maximum immune response after first dose vaccination | 3weeks from the first-dose administration in BNT162b2 group, 8-12weeks from the first-dose administration in ChAdOx1 | 
| Antibody titres after the second dose vaccination | This study aimed to analyze maximum immune response after second dose vaccination | 3 weeks from the second dose administration in both BNT162b2 and ChAdOx1 groups |