A recent study has also described the existence of such cross-reactive T cell epitopes between the A/California/07/2009 H1N1 strain and seasonal strains contained in the 2008–2009 TIV formulation, which contains the same A/Brisbane/59/2007 (H1N1) strain as the TV2 vaccine formulation used in our present study [14]. Furthermore, intra-subtype influenza priming has been reported to induce CD4+

helper T cells that are essential for antibody production [15]. In contrast to observations with non-adjuvanted vaccine, seasonal influenza priming did not appear to influence the immunogenicity of the AF03-adjuvanted vaccine formulations, likely due to a strong primary response induced by the adjuvanted vaccine in these groups of mice. The immunogenicity results of these studies with AF03-adjuvanted H1N1 selleck products vaccine in mice are consistent with clinical studies of H5N1 influenza vaccines, in which HI responses were significantly increased by the addition of this emulsion-based adjuvant. Without adjuvant, H5N1 vaccines generally have been observed to be weakly immunogenic, even at HA doses of 30 μg HA or higher, whereas an AF03-adjuvanted H5N1 vaccine was demonstrated to elicit antibody responses to protective click here levels in humans at doses of as little as 1.9 μg

of HA [16] and [17]. In conclusion, the results of these studies in mice support the use in humans of a split-virion inactivated pandemic (H1N1) 2009 vaccine formulated with or without AF03 adjuvant. The use of non-adjuvanted vaccine may be of particular interest for use in specific populations such as immunosuppressed individuals or pregnant women, for whom health authorities have stated a preference for such vaccines [18]. However, since a guiding principle in the recommendations of health

authorities for immunization against pandemic influenza has been to vaccinate as many persons as possible as quickly as possible, and since the use of AF03-adjuvanted vaccine offers the possibility of significant HA antigen dose-sparing, its use would help to meet future demand for pandemic tuclazepam influenza vaccines in a larger proportion of the world’s population. The authors thank the following contributors at sanofi pasteur, France: Antonin Asmus, Julie Barrier, Sarah Clement-Fartouh, Sylvie Commandeur, Arnaud Cangialosi, Valérie Gautier, Sandrine Montano, Danièle Rossin, Christelle Serraille, Tharwa Shehada, Céline Vaure for their excellent technical support in HI and SN analysis and animal experimentations, and Grenville Marsh who provided editorial assistance. “
“Despite significant medical advances and the improvement of human health, the control and eventual eradication of infectious diseases remain major challenges to public health in both developed and developing countries.