biostudies-literatureUnknown31(3)Moris P<h4>Objective</h4>Adjuvantation of an H5N1 split-virion influenza vaccine with AS03(A) substantially reduces the antigen dose required to produce a putatively protective humoral response and promotes cross-clade neutralizing responses. We determined the effect of adjuvantation on antibody persistence and B- and T-cell-mediated immune responses.<h4>Methods</h4>Two vaccinations with a split-virion A/Vietnam/1194/2004 (H5N1, clade 1) vaccine containing 3.75-30 ?g hemagglutinin and formulated with or without adjuvant were administered to groups of 50 volunteers aged 18-60 years.<h4>Results</h4>Adjuvantation of the vaccine led to better persistence of neutralizing and hemagglutination-inhibiting antibodies and higher frequencies of antigen-specific memory B cells. Cross-reactive and polyfunctional H5N1-specific CD4 T cells were detected at baseline and were amplified by vaccination. Expansion of CD4 T cells was enhanced by adjuvantation.<h4>Conclusion</h4>Formulation of the H5N1 vaccine with AS03(A) enhances antibody persistence and induces stronger T- and B-cell responses. The cross-clade T-cell immunity indicates that the adjuvanted vaccine primes individuals to respond to either infection and/or subsequent vaccination with strains drifted from the primary vaccine strain.Journal of clinical immunology443-54https://www.ebi.ac.uk/biostudies/studies/S-EPMC3132412biostudies-literatureH5N1 influenza vaccine formulated with AS03 A induces strong cross-reactive and polyfunctional CD4 T-cell responses.PMC3132412Clement Fvan der Most RHanon EDrame MLeroux-Roels ILeroux-Roels GGVan Mechelen MMoris PfalseH5N1 influenza vaccine formulated with AS03 A induces strong cross-reactive and polyfunctional CD4 T-cell responses.<h4>Objective</h4>Adjuvantation of an H5N1 split-virion influenza vaccine with AS03(A) substantially reduces the antigen dose required to produce a putatively protective humoral response and promotes cross-clade neutralizing responses. We determined the effect of adjuvantation on antibody persistence and B- and T-cell-mediated immune responses.<h4>Methods</h4>Two vaccinations with a split-virion A/Vietnam/1194/2004 (H5N1, clade 1) vaccine containing 3.75-30 ?g hemagglutinin and formulated with or without adjuvant were administered to groups of 50 volunteers aged 18-60 years.<h4>Results</h4>Adjuvantation of the vaccine led to better persistence of neutralizing and hemagglutination-inhibiting antibodies and higher frequencies of antigen-specific memory B cells. Cross-reactive and polyfunctional H5N1-specific CD4 T cells were detected at baseline and were amplified by vaccination. Expansion of CD4 T cells was enhanced by adjuvantation.<h4>Conclusion</h4>Formulation of the H5N1 vaccine with AS03(A) enhances antibody persistence and induces stronger T- and B-cell responses. The cross-clade T-cell immunity indicates that the adjuvanted vaccine primes individuals to respond to either infection and/or subsequent vaccination with strains drifted from the primary vaccine strain.2011-01-01T00:00:00Z2011 Jun2021-03-18T08:06:38Z2019-03-27T03:06:53ZS-EPMC31324122117414410.1007/s10875-010-9490-6