This is an exploratory, laboratory-based evaluation of cellular immune response to immunization with hepatitis B surface antigen in HIV-infected and HIV-uninfected adolescents. This is a substudy of ATN 024 and ATN 025. This substudy will compare cellular immune response in responders and nonresponders to immunization and also evaluate the relationship of these factors to the persistence of known correlates of serologic protection for the hepatitis B virus.
This substudy will enroll volunteers from participants of ATN 024 and ATN 025. Participants in ATN 024 are HIV-infected youths aged 12-24 years while participants in ATN 025 are HIV-uninfected youths aged 12-17 years. These youths must also be negative for HBV core antibody, HBV surface antigen, and HBV surface antibody to be eligible. Blood will be drawn from study participants prior to immunization, 1 month after completion of primary immunization and at study exit (week 72 for ATN 024 and week 76 for ATN 025) for cytokine assays and enumeration of antibody-secreting cells. In addition, the antibody to HBV surface antigen will be determined 2 and 4 weeks after supplemental immunization in nonresponders to the primary series and at study exit. This laboratory substudy is designed to evaluate some aspects of cellular immune response to hepatitis B vaccination that are directly related to the generation and durability of antibody response to HBV surface antigen in HIV-infected and HIV-uninfected adolescents. Cytokine production by peripheral mononuclear cells will be determined following in-vitro stimulation, and antibody-secreting cells will be enumerated.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
95
Standard adult dose for A1; increased adult dose for A2. Doses at Entry, Weeks 4 and 24. Non-responders (\<10 IU/mL of antibody at week 28/4 weeks after dose #3) will receive Engerix-B increased adult dose at Week 48.
Standard adult dosage, taken at Entry, Weeks 4 and 24. Non-responders (\<10 IU/mL of antibody at week 28/4 weeks after dose #3) will receive Engerix-B increased adult dose at week 48.
Dosage at entry and week 24; non-responders ((\<10 IU/mL of antibody at week 28/4 weeks after dose #3) will receive 3rd dose of Recombivax during weeks 48-72.
Childrens Hosp of Los Angeles
Los Angeles, California, United States
University of California at San Francisco
San Franciso, California, United States
Children's Hosp Natinal Med Center
Washington D.C., District of Columbia, United States
Tulane Med Center
New Orleans, Louisiana, United States
To measure interferon-γ (IFN-γ), interleukin -4 (IL-4), and interleukin-10 (IL-10) production in serologic responders and non-responders.
Time frame: Before and one month after receipt of primary series of immunization.
To measure concentration of hepatitis B antibodies in serologic responders and non-responders.
Time frame: 1, 2, and 4 weeks after supplemental vaccine dose.
To measure concentration of antibody-secreting cells in serologic responders and non-responders.
Time frame: Before and one month after receipt of primary series of immunization.
Measure whether the profile of cytokine secretion or the number of antibody-secreting cells can be used as a predictor of anamnestic response to a supplemental vaccine dose following serologic nonresponse to a primary series of immunization.
Time frame: Prior to immunization, 1 month after primary immunization, at study exit (week 72 for ATN 024; week 76 for ATN 025); at 2 & 4 weeks after supplemental immunization in nonresponders, & at study exit for ATN 024 subjects.
To compare the rate of loss of antibody-secreting cells after vaccination through the end of the study in each vaccine arm.
Time frame: Prior to immunization, 1 month after completion of primary immunization and at study exit.
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Doses at Entry and Week 24. Non-responders (\<10 IU/mL of antibody at week 28/4 weeks after dose #3) will receive a dose of Recombivax during week 48-72.