Characterization of Human Memory Immune Responses to Prior Yellow Fever Vaccination

Yellow Fever Vaccine Clinical Trial

Official title:

Characterization of Human Memory Immune Responses to Prior Yellow Fever Vaccination

Clinical Trial Details — Status: Enrolling by invitation

Administrative data

• NCT number: NCT01244802
• Other study ID #: IRB00002834
• Secondary ID: U19AI057266
• Status: Enrolling by invitation
• Start date: November 2010
• Est. completion date: June 2024

Study information

• Verified date: December 2023
• Source: Emory University
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The objective of this study is to study immune memory generated against the yellow fever (YFV) vaccine in participants who have previously received the vaccine. Volunteers will not receive vaccine shots; only immune responses to previous yellow fever vaccination will be studied. The study involves one or multiple blood draws.

Description:

The goal of this study is to characterize immune memory in humans who have previously received yellow fever vaccine. The project is designed to study the magnitude and persistence of both humoral, and cell-mediated immune memory generated post-vaccination. Since aging has an effect on the immune system (eg. decreased thymic output, replacement of hematopoietic cells in the bone marrow with adipocytes), the researchers will analyze the young adults (aged 18-45 years) and the older vaccinees (55 years or older) in separate groups.

The specific aims of the study are to:

• Determine the phenotypic and functional characterization of memory T cell responses to yellow fever vaccination

• Determine neutralizing antibody titer after yellow fever vaccination

Recruitment information / eligibility

• Status: Enrolling by invitation
• Enrollment: 300
• Est. completion date: June 2024
• Est. primary completion date: June 2024
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Able to understand and give informed consent

• Age 18-45 years (Group 1) or 55 years and above (Group 2) at the time of yellow fever vaccination

• Documentation (international certificate of vaccination (yellow card) or medical record) indicating receipt of yellow fever vaccine.

Exclusion Criteria:

• Recipient of any vaccines within 30 days before the study visit (not applicable to older adults)

• History of a progressive and severe chronic medical condition resulting in impaired immunity (such as diabetes, kidney or liver dysfunction)

• Required use of immunosuppressive medications

• Reporting HIV, Hepatitis B (surface antigen positive) or Hepatitis C infections (antibody positive) on the medical/health history form

• Recipient of a blood product or immune globulin product within 42 days of study visit

• Reporting pregnancy

Related Conditions & MeSH terms

• Fever
• Yellow Fever
• Yellow Fever Vaccine

Locations

Country	Name	City	State
United States	The Hope clinic of Emory Vaccine Center	Decatur	Georgia

Sponsors (2)

Lead Sponsor	Collaborator
Emory University	National Institute of Allergy and Infectious Diseases (NIAID)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Determine the phenotypic and functional characterization of memory T cell responses to YF vaccination	This is an exploratory analysis of variation in immune response with time since last yellow fever virus vaccination.	Immune responses will be measured from at least 30 days after yellow fever vaccination.