Immunological Tolerance After Frequent Rabies Booster Vaccinations

Study Overview
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Brief Summary
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To study immunological tolerance effect after frequent rabies booster vaccination

Detailed Description
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Previous studies had shown lower antibody titers among those who received frequent rabies booster vaccination, compared to ones who had got primary immunization. We study immunological cells i.e., regulatory T cell, regulatory B cell, T follicular helper cell, and cytokines in those who received frequent rabies booster vaccination.

Official Title
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Immunological Tolerance After Frequent Rabies Booster Vaccinations

Conditions
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Rabies

Intervention / Treatment
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* Biological: Blood drawn after rabies vaccine booster vaccination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy adults Previously received rabies vaccination Exclusion Criteria: Had immunocompromised conditions Received blood or blood product within 3 months Received anti-malarial drugs

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 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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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: There would be two study groups. Those who had received primary immunization would be the control group. While persons who had received primary immunization and later received booster vaccination for at least 3 times would be the study group. All participants would be given one dose of rabies vaccine and monitored the immunological cells and cytokines before and after the rabies booster injection.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control group<br>Persons who had received primary immunization | Biological: Blood drawn after rabies vaccine booster vaccination<br>* All participants would be given one dose of rabies vaccine and monitor the immunological cells i.e., regulatory T cell, regulatory B cell, T follicular helper cells, cytokines i.e., IL-10, TGF-Beta, and Rabies neutralizing antibody titers, before and after the booster injection<br>|
| Experimental: Study group<br>Persons who had received primary immunization and later received booster vaccination for at least 3 times | Biological: Blood drawn after rabies vaccine booster vaccination<br>* All participants would be given one dose of rabies vaccine and monitor the immunological cells i.e., regulatory T cell, regulatory B cell, T follicular helper cells, cytokines i.e., IL-10, TGF-Beta, and Rabies neutralizing antibody titers, before and after the booster injection<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rabies specific regulatory T cells | Rabies specific regulatory T cells are measured by flow cytometry method | Change from baseline of numbers of Rabies specific regulatory T cells before (baseline) and one month after receipt of rabies booster vaccination were compared between 2 arms | 
| Rabies specific regulatory B cells | Rabies specific regulatory B cells are measured by flow cytometry method | Change from baseline of numbers of Rabies specific regulatory B cells before (baseline) and one month after receipt of rabies booster vaccination were compared between 2 arms | 
| Rabies specific T follicular helper cells | Rabies specific T follicular helper cells are measured by flow cytometry method | Change from baseline of numbers of Rabies specific T follicular helper cells before (baseline) and one month after receipt of rabies booster vaccination were compared between 2 arms | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rabies Neutralizing Antibody Titers (RNab) | Rabies Neutralizing Antibody Titers would be represented and compared by geometric mean titers (GMTs) | before (baseline) and one month after receipt of rabies booster vaccination | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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rabies vaccination