Co-administration of certain DNA vaccine combinations expressing different H5N1 influenza virus antigens can be beneficial or detrimental to immune protection.

摘要: Abstract Achieving broad-spectrum immunity against emerging zoonotic viruses such as avian influenza H5N1 and other possible pandemic will require generation of cross-protective immune responses. Strong antibody responses generated the H5HA protein are protective, however, antigenic variation between diverging isolates can interfere with virus neutralization. The current study investigates co-administration an H5 HA DNA vaccine variable conserved antigens (NA, NP, M2). All were derived from A/Hanoi/30408/2005 (H5N1) contribution towards overall protection activation was assessed lethal homologous heterologous challenges. An (HA + NA) combination afforded best challenge (HA + NP) comparable to alone A/Hong Kong/483/1997 challenge. Interestingly, combining all four at a single site did not improve matched unexpectedly reduced survival by 30% Survival also significantly decreased following unrelated antigen. Although there no significant changes in titres, lower T-cell detected except each combination. Co-administration vaccines different injection sites restored but protection. Similar observations recorded NP using two adenovirus-based backbones. Overall, data suggest that co-administering certain offer better or alone, extra may be unnecessary lead unfavourable