Turnover of Antigen Specific Lymphocytes After Immunization With the Yellow Fever Vaccine
The yellow fever vaccine is a live, attenuated virus that results in a robust immune response, especially in the T cell compartment. We have been studying immune responses to live viral infections using the yellow fever vaccine as a model for a live viral infection. In this study, we are interested in looking at the processing and lifespan of yellow fever specific CD8 T cells.
We plan to accomplish this by measuring DNA replication and cell proliferation in humans using a naturally occurring stable isotope called deuterium (D20). This technique has been used to track the turnover of a number of human cell types in vivo. We plan to use D20 labeling to track YFV specific CD8+ T cells in human vaccinees who are positive for a specific HLA type, HLA A202.
Deuterium labeled water (D2O), also known as heavy water is physically and chemically very similar to ordinary drinking water. In water, two hydrogen atoms bond to an oxygen and create H20. However in deuterated water, deuterium atoms replace the hydrogen atoms. Deuterium is a form of hydrogen that has an extra neutron. This neutron gives the atom extra weight, hence the name "heavy water." This extra weight can be detected in the lab with very sensitive instruments. Scientists have been using heavy water as a tracer to gain a better understanding of animal and human metabolic rates. Deuterium is in fact already in the water we drink daily. It is not radioactive, and it occurs naturally at a concentration of about 1 part per 5,000. Researchers have used heavy water since 1934 as a safe and effective tool in clinical trials.
|Yellow Fever||Biological: Yellow fever vaccine Biological: Yellow fever vaccine and D20 water|
|Study Design:||Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
|Official Title:||Turnover of Antigen Specific Lymphocytes After Immunization With the 17D Yellow Fever Vaccine|
- To evaluate the life span and decay curve of effector CD8 T cells after immunization with 17D yellow fever vaccine [ Time Frame: CD8 T cells will be measured on days 14, 21 and at weeks 6, 10, 14, 18, 22, 26, 32, 36, 40, 44, 48 and 52 after vaccination ]The life span and decay curve of yellow specific effector CD8 T cells will be detected by deuterium labeling
- To evaluate the rate of homeostatic turnover of memory CD8 T cells after immunization with 17D yellow fever vaccine [ Time Frame: CD8 T cells will be measured on days 14, 28, weeks 8,9,,10,11,12, 24, 25, 26, 27 , 28 after vaccination ]
|Study Start Date:||February 2011|
|Estimated Study Completion Date:||January 2020|
|Estimated Primary Completion Date:||January 2020 (Final data collection date for primary outcome measure)|
Experimental: Group 1
In group 1, participants will receive the Yellow fever vaccine and will be asked to drink deuterium labeled water for 2 weeks. They will undergo phlebotomy on days 0, 14, 21, weeks 6, 10, 14, 18, 22, 26, 32, 36, 40, 44, 48 and 52.
Biological: Yellow fever vaccine
Group 1: All participants will receive the yellow fever vaccine and will be asked to drink deuterium labeled water and will undergo serial blood draws over 1 year.
Other Name: YF-VAX
Experimental: Group 2
All participants in Group 2 will receive the yellow fever vaccine and will drink deuterium labeled for 3 weeks and will undergo serial phlebotomy for upto 7 months.
Biological: Yellow fever vaccine and D20 water
Eligible participants will receive the yellow fever vaccine and will drink D20 water
Other Name: YF-VAX
Please refer to this study by its ClinicalTrials.gov identifier: NCT01290055
|Contact: Eileen Osinskiemail@example.com|
|Contact: Shashi Nagarfirstname.lastname@example.org|
|United States, Georgia|
|The Hope clinic of Emory Vaccine Center||Recruiting|
|Decatur, Georgia, United States, 30030|
|Contact: Eileen Osinski 404-727-8435 email@example.com|
|Principal Investigator:||Srilatha Edupuganti, MD||Emory University|