title: Differential effect of interleukin-2 treatment on primary and secondary immunizations in HIV infected individuals.
abstract: OBJECTIVE
  As interleukin (IL)-2 therapy increases CD4 cell counts in HIV infected subjects, it emerged as a candidate for the partial restoration of immune competence in this disease.
  
  
  METHODS
  We studied the frequencies of antigen-specific T cells using single cell resolution cytokine ELISPOT assays and titers of specific antibodies before and after immunization of HIV infected subjects who were treated with HAART or HAART plus IL-2.
  
  
  RESULTS
  Subjects seronegative to hepatitis A were vaccinated with hepatitis A antigen. In the non-IL-2 treated group, hepatitis A-specific T cells producing IL-2 and IL-4 along with specific antibodies were induced, showing that these subjects are immune competent and capable of mounting a primary immune response. Additional IL-2 treatment had no significant effect on this primary T cell response; however, booster immunizations with tetanus toxoid or the gp120 depleted HIV vaccine Remune induced higher frequencies of specific interferon (IFN)-gamma producing T cells in IL-2 treated subjects. No impact of IL-2 treatment on these secondary B cell responses was seen.
  
  
  CONCLUSIONS
  Overall, our study showed that IL-2 therapy had no immune enhancing effect on the induction of a primary response, but increased the frequency of IFN-gamma producing memory cells after booster immunization.
authors.affiliation: Department of Pathology, Case Western Reserve University and University Hospitals of Cleveland, Cleveland, Ohio 44116, USA.
authors.forename: Haydar
authors.initials: H
authors.lastname: Kuekrek
authors.forename: Tobias
authors.initials: T
authors.lastname: Schlingmann
authors.forename: Hernan
authors.initials: H
authors.lastname: Valdez
authors.forename: Bernhard O
authors.initials: BO
authors.lastname: Boehm
authors.forename: Richard B
authors.initials: RB
authors.lastname: Pollard
authors.forename: Ronald
authors.initials: R
authors.lastname: Mitsuyasu
authors.forename: Frank-Detlef
authors.initials: FD
authors.lastname: Goebel
authors.forename: Michael M
authors.initials: MM
authors.lastname: Lederman
authors.forename: Paul V
authors.initials: PV
authors.lastname: Lehmann
authors.forename: Magdalena
authors.initials: M
authors.lastname: Tary-Lehmann
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology; D000917:Antibody Formation / Q000276:immunology; D000918:Antibody Specificity / Q000276:immunology; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods; D001402:B-Lymphocytes / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D016655:HIV Core Protein p24 / Q000276:immunology; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology*; D006506:Hepatitis A / Q000276:immunology; D035921:Hepatitis A Antigens / Q000276:immunology; D006509:Hepatitis B / Q000276:immunology; D006801:Humans; D007114:Immunization / Q000379:methods*; D007117:Immunization, Secondary / Q000379:methods; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology*; D015847:Interleukin-4 / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D013744:Tetanus Toxin / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
chemical_list: D016915:AIDS Vaccines; D016655:HIV Core Protein p24; D035921:Hepatitis A Antigens; D007376:Interleukin-2; D013744:Tetanus Toxin; D015847:Interleukin-4; D007371:Interferon-gamma