tetano
Editor, Senior Moderator
Hum Vaccin Immunother. 2016 Oct 21:0. [Epub ahead of print]
[h=1]Low hemagglutinin antigen dose influenza vaccines adjuvanted with AS03 alter the long-term immune responses in BALB/c mice.[/h] Yam KK[SUP]1[/SUP], Brewer A[SUP]1[/SUP], Bleau V[SUP]1[/SUP], Beaulieu ?[SUP]2,[/SUP][SUP]3[/SUP], Mallett CP[SUP]2[/SUP], Ward BJ[SUP]1,[/SUP][SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] We investigated the long-term immune profiles of dose-sparing, AS03-adjuvanted vaccines compared to a traditional high-dose, unadjuvated influenza vaccine formulations. BALB/c mice received 2 IM injections of influenza A/Uruguay/716/2007 (H3N2) split vaccine antigen: high-dose (HD) (3 ?g hemagglutinin (HA)/dose) or low-dose (LD) formulations (0.03 ?g or 0.003 ?g HA) with AS03 and were followed to 34 weeks post-boost (pb). We examined serologic responses, spleen and bone marrow (BM) HA-specific antibody-secreting cells (ASCs) by ELISpot, influenza-specific cytokine/chemokine production in re-stimulated splenocytes by multiplex ELISA, and antigen-specific CD4+ T cells that express cytokines (IL-2, IFNγ, TNFa and IL-5) by flow cytometry. All formulations elicited robust serum antibody titers that persisted for at least 34 weeks. The number of antigen-specific ASCs in the spleen and BM were higher in the two LD +AS03 groups, but despite having fewer ASCs, the average spot size in the HD-unadjuvanted group was larger at later time-points, suggesting greater antibody production per cell. Striking differences in the long-term profiles induced by the different vaccine formulations may contribute to these different ASC profiles. The HD-unadjuvanted vaccine elicited strong Th2 cytokines during the first 6 weeks pb but LD+AS03 groups generated broader, more durable responses at later timepoints. Finally, the 0.03 ?g HA+AS03 group generated the greatest number of antigen-specific CD4+ T cells and the highest percentage of poly-functional cells that expressed two or more cytokines. Although all of the tested vaccines induced durable antibody responses, we show that different vaccine formulations (dose-sparing, adjuvant) generate distinct long-term immune profiles. Furthermore, our data suggest that the different profiles may be generated through unique mechanisms.
[h=4]KEYWORDS:[/h] AS03; adjuvant; antibody-secreting cells; chemokine; cytokine; dose-sparing; hemagglutination inhibition; influenza; long-term immune response; microneutralization; vaccine
PMID: 27768511 DOI: 10.1080/21645515.2016.1241360
[PubMed - as supplied by publisher]
[h=1]Low hemagglutinin antigen dose influenza vaccines adjuvanted with AS03 alter the long-term immune responses in BALB/c mice.[/h] Yam KK[SUP]1[/SUP], Brewer A[SUP]1[/SUP], Bleau V[SUP]1[/SUP], Beaulieu ?[SUP]2,[/SUP][SUP]3[/SUP], Mallett CP[SUP]2[/SUP], Ward BJ[SUP]1,[/SUP][SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] We investigated the long-term immune profiles of dose-sparing, AS03-adjuvanted vaccines compared to a traditional high-dose, unadjuvated influenza vaccine formulations. BALB/c mice received 2 IM injections of influenza A/Uruguay/716/2007 (H3N2) split vaccine antigen: high-dose (HD) (3 ?g hemagglutinin (HA)/dose) or low-dose (LD) formulations (0.03 ?g or 0.003 ?g HA) with AS03 and were followed to 34 weeks post-boost (pb). We examined serologic responses, spleen and bone marrow (BM) HA-specific antibody-secreting cells (ASCs) by ELISpot, influenza-specific cytokine/chemokine production in re-stimulated splenocytes by multiplex ELISA, and antigen-specific CD4+ T cells that express cytokines (IL-2, IFNγ, TNFa and IL-5) by flow cytometry. All formulations elicited robust serum antibody titers that persisted for at least 34 weeks. The number of antigen-specific ASCs in the spleen and BM were higher in the two LD +AS03 groups, but despite having fewer ASCs, the average spot size in the HD-unadjuvanted group was larger at later time-points, suggesting greater antibody production per cell. Striking differences in the long-term profiles induced by the different vaccine formulations may contribute to these different ASC profiles. The HD-unadjuvanted vaccine elicited strong Th2 cytokines during the first 6 weeks pb but LD+AS03 groups generated broader, more durable responses at later timepoints. Finally, the 0.03 ?g HA+AS03 group generated the greatest number of antigen-specific CD4+ T cells and the highest percentage of poly-functional cells that expressed two or more cytokines. Although all of the tested vaccines induced durable antibody responses, we show that different vaccine formulations (dose-sparing, adjuvant) generate distinct long-term immune profiles. Furthermore, our data suggest that the different profiles may be generated through unique mechanisms.
[h=4]KEYWORDS:[/h] AS03; adjuvant; antibody-secreting cells; chemokine; cytokine; dose-sparing; hemagglutination inhibition; influenza; long-term immune response; microneutralization; vaccine
PMID: 27768511 DOI: 10.1080/21645515.2016.1241360
[PubMed - as supplied by publisher]