Project description:Influenza A virus (FLUAV) poses a significant threat to both humans and animals. While vaccination serves as the primary defense against influenza, the effectiveness of currently approved vaccines is suboptimal. To address this issue, we have developed modified live virus (MLV) vaccines against influenza using genome rearrangement techniques targeting the internal gene segments of FLUAV. The rearranged M2 (RAM) strategy involves cloning the M2 ORF downstream of the PB1 ORF in segment 2 and incorporating multiple early stop codons within the M2 ORF in segment 7. Additionally, the IgA-inducing protein (IGIP) coding region was inserted into the HA segment to further attenuate the virus and enhance protective mucosal responses. RAM-IGIP viruses exhibit similar growth rates to wild type (WT) viruses in vitro and remain stable during multiple passages in cells and embryonated eggs. The safety, immunogenicity, and protective efficacy of the RAM-IGIP MLV vaccine against the prototypical 2009 pandemic H1N1 strain A/California/04/2009 (H1N1) (Ca/04) were evaluated in Balb/c mice and compared to a prototypic cold-adapted live attenuated virus vaccine. The results demonstrate that the RAM-IGIP virus exhibits attenuated virulence in vivo. Mice vaccinated with RAM-IGIP and subsequently challenged with an aggressive lethal dose of the Ca/04 strain exhibited complete protection. Analysis of the humoral immune response revealed that the inclusion of IGIP enhanced the production of neutralizing antibodies and augmented the antibody-dependent cellular cytotoxicity response. Similarly, the RAM-IGIP potentiated the mucosal immune response against various FLUAV subtypes. Moreover, increased antibodies against NP and NA responses were observed. These findings support the development of MLVs utilizing genome rearrangement strategies in conjunction with the incorporation of immunomodulators.
Project description:Recent avian and swine-origin influenza virus outbreaks illustrate the ongoing threat of influenza pandemic. New vaccines that offer accelerated production and broader, more universal protection against drifted and shifted strains are needed. Here, we investigated a multivalent PMED DNA vaccine for the ability to induce antibody and T cell responses against four HA antigens, nucleoprotein and the ectodomain of M2 (M2e).
Project description:Influenza immunization during pregnancy provides protection to the mother and the infant. Studies in adults and children with inactivated influenza vaccine (IIV) have identified changes in immune gene expression that correlated with antibody responses. We studied changes in transcriptional profiles induced by IIV in pregnant women and to identify correlates of antibody responses.
Project description:The M2-2 protein from the respiratory syncytial virus (RSV) is a 10 kDa protein expressed by the second ORF of the viral gene M2. During infection, M2-2 has been described as the polymerase cofactor responsible for promoting genome replication. This function was first inferred by infection with a mutant virus lacking the M2-2 ORF, in which viral genome presented delayed accumulation in comparison to wild-type virus. In accordance with this phenotype, it has been recently shown that M2-2 promotes changes in interactions between the polymerase and other viral proteins at early stages of infection. Despite its well explored role in the regulation of the polymerase activity, little has been made to investigate the relationship of M2-2 with cellular proteins. In fact, previous reports showed poor recruitment of M2-2 to viral structures, with the protein being mainly localized to the nucleus and cytoplasmic granules. To unravel which other functions M2-2 exerts during infection, we expressed the protein in HEK293T cells and performed proteomic analysis of co-immunoprecipitated partners, identifying enrichment of proteins involved with regulation of translation, protein folding and mRNA splicing. In approaches based on these data, we found that M2-2 expression downregulates eiF2α phosphorylation and inhibits stress granules assembly under arsenite induction. In addition, we also verified that M2-2 inhibits translation initiation, and is targeted for proteasome degradation, being localized to granules composed by defective ribosomal products at the cytoplasm. These results suggest that besides its functions in the regulation of genome replication, M2-2 may exert additional functions to contribute to successful RSV infection.
Project description:Combining variant antigens into a multivalent vaccine is a traditional approach used to provide broad coverage against antigenically variable pathogens, such as polio, human papilloma and influenza viruses. However, strategies for increasing the breadth of antibody coverage beyond the vaccine are not well understood, but may provide more anticipatory protection. Influenza virus hemagglutinin (HA) is a prototypic variant antigen. Vaccines that induce HA-specific neutralizing antibodies lose efficacy as amino acid substitutions accumulate in neutralizing epitopes during influenza virus evolution. Here we studied the effect of a potent combination adjuvant (CpG/MPLA/squalene-in-water emulsion) on the breadth and maturation of the antibody response to a representative variant of HA subtypes H1, H5 and H7. Using HA protein microarrays and antigen-specific B cell labelling, we show when administered individually, each HA elicits a cross-reactive antibody profile for multiple variants within the same subtype and other closely-related subtypes (homosubtypic and heterosubtypic cross-reactivity, respectively). Despite a capacity for each subtype to induce heterosubtypic cross-reactivity, broader coverage was elicited by simply combining the subtypes into a multivalent vaccine. Importantly, multiplexing did not compromise antibody avidity or affinity maturation to the individual HA constituents. The use of adjuvants to increase the breadth of antibody coverage beyond the vaccine antigens may help future-proof vaccines against newly-emerging variants.
Project description:The purpose of this study was to investigate the anatomic sites and mechanisms of antibody-mediated protection. In particular, to determine whether bNAbs completely block virus at the local portal of entry following mucosal virus challenge.
Project description:Recent avian and swine-origin influenza virus outbreaks illustrate the ongoing threat of influenza pandemic. New vaccines that offer accelerated production and broader, more universal protection against drifted and shifted strains are needed. Here, we investigated a multivalent PMED DNA vaccine for the ability to induce antibody and T cell responses against four HA antigens, nucleoprotein and the ectodomain of M2 (M2e). Macaques in the Vaccinated and Control groups were intramuscularly anaesthetized with ketamine (10 mg/kg) and inoculated with a suspension containing 10^6.5 p.f.u. ml-1 of CA09 virus through a combination of intratracheal (4.5 ml), intranasal (0.5 ml per nostril), ocular (0.1 ml per eye) and oral (1 ml) routes (resulting in a total infectious dose of 10^7.4 PFU). Bronchoalveolar lavages were collected two weeks prior to challenge and at days 3, 7, and 10 post-infection. We performed microarray analysis on these samples.
Project description:BRD4 inhibition suppressed M2 macrophage polarization. Particularly, we deeply investigated the underlying molecular mechanism of how BRD4 epigenetically regulate M2 genes expression. And finished the cut&tag experiment using BRD4, H3K27ac, IRF4 as antibody to find out the binding sites change in M2 macrophage treated with ARV825.
Project description:LAIV and TIV are effective for prevention of influenza infection in children, but the mechanisms associated with protection are still not well defined. We analyzed the differences in B cell responses and transcriptional profiles. Compared to baseline, LAIV elicited a significant increase in naïve, memory and transitional B cells on day 30, while vaccination with TIV elicited an increase in number of plasmablasts on day 7. Antibody titers against the three vaccine strains (H1N1, H3N2 and B) were significantly higher in the TIV group and correlated with number of antibody-secreting cells. Regarding transcriptional profiles, both vaccines induced expression of interferon signaling, but at different time points, TIV on 1 day, and LAIV on day 7 day post-vaccination, the last only in children younger than 5 years old. Interferon-related genes over expressed in both vaccinated groups correlated with antibody titers of H3N2 vaccines strain. These results suggest that LAIV and TIV induced significant different B cell responses in vaccinated children. Early induction on interferon genes appears important for development of effective antibody responses.
Project description:Interventions: The influenza virus vaccine is given in the period October/November 2011.
Primary outcome(s): Adequate rise in antibody titre.
Study Design: Randomized controlled trial, Open (masking not used), Active, Parallel
