Immunogenicity and effect of a virosomal influenza vaccine on viral replication and T-cell activation in HIV-infected children receiving highly active antiretroviral therapy.
In order to evaluate the immunogenicity and the effect of a virosomal influenza vaccine on viral replication and T-cell activation in HIV-infected children receiving highly active antiretroviral therapy (HAART), 29 children infected with HIV-1 vertically (19 primed with a previous influenza vaccination and 10 who were not been immunized against influenza) were immunized with an intramuscular virosome-adjuvanted influenza vaccine. According to the European Agency for Evaluation of Medical Products (EMEA) criteria, the immunogenicity of the vaccine was adequate against all three influenza strains (A H1N1, A H3N2, and B) in the primed children, and against A H1N1 and A H3N2 in the unprimed children. After in vitro stimulation with vaccine antigens, the IFN-gamma levels in the peripheral blood mononuclear cells cultures increased significantly from a baseline level of 103.0 +/- 229.8 pg/ml to a 30-day level of 390.7 +/- 606.3 pg/ml (P < 0.05), with concentrations significantly higher (P < 0.05) in the primed children than in the unprimed children. No increase in plasma HIV-1 RNA or HIV-1 proviral DNA was observed in either subgroup, and the immunophenotype analyses demonstrated that the CD4+ cell counts and percentages, the CD4/CD8 ratio and activated lymphocytes remained stable in either group from baseline to 1 month after each vaccine dose. This study showed that the virosomal influenza vaccine does seem to be immunogenic in the majority of HIV-infected children receiving HAART and does not induce viral replication or T-cell activation. Given the possible influenza-related complications in children infected with HIV, these results support the use of this influenza vaccine in such patients.
Department of Public Health-Microbiology-Virology, University of Milan, Milan, Italy.
Elisabetta
E
Tanzi
Susanna
S
Esposito
Jelena
J
Bojanin
Antonella
A
Amendola
Daria
D
Trabattoni
Elena
E
Pariani
Raffaella
R
Pinzani
Alessandro
A
Zanetti
Nicola
N
Principi
D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood; D023241:Antiretroviral Therapy, Highly Active; D002648:Child; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology; D015497:HIV-1 / Q000187:drug effects / Q000502:physiology; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology; D009981:Influenza B virus / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000276:immunology; D007251:Influenza, Human / Q000276:immunology / Q000517:prevention & control*; D007371:Interferon-gamma / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008297:Male; D013601:T-Lymphocytes / Q000276:immunology; D016896:Treatment Outcome; D019562:Viral Load; D022701:Virosomes; D014779:Virus Replication
D000914:Antibodies, Viral; D007252:Influenza Vaccines; D022701:Virosomes; D007371:Interferon-gamma