Differential effect of interleukin-2 treatment on primary and secondary immunizations in HIV infected individuals.
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.
Kuekrek
Haydar
H
Department of Pathology, Case Western Reserve University and University Hospitals of Cleveland, Cleveland, Ohio 44116, USA.
Schlingmann
Tobias
T
Valdez
Hernan
H
Boehm
Bernhard O
BO
Pollard
Richard B
RB
Mitsuyasu
Ronald
R
Goebel
Frank-Detlef
FD
Lederman
Michael M
MM
Lehmann
Paul V
PV
Tary-Lehmann
Magdalena
M
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
D016915:AIDS Vaccines; D016655:HIV Core Protein p24; D035921:Hepatitis A Antigens; D007376:Interleukin-2; D013744:Tetanus Toxin; D015847:Interleukin-4; D007371:Interferon-gamma