Synthetic peptide-based vaccines against influenza

Abstract

Advances have been made in the development of vaccines based on synthetic peptides representing protective epitopes of the influenza virus. The study reviewed here evaluates the capacity of three epitopes in different delivery systems to induce specific immune response and protect mice against viral challenge infection. Although peptide vaccines are not in use yet, they continue to be explored as is discussed herewith.

Characterization of a branched lipopeptide candidate vaccine against influenza A/Puerto Rico 8/34 which is recognized by human B and T-cell immune responses

“…Neutralizing antibodies, specifically those directed at the HA protein, have been characterized as being of major importance in protection against influenza infection [ 3 , 32 , 37 , 38 ]. The ELISAs above measured direct antibody binding, but not all these antibodies may be neutralizing; this assay assesses binding of all virus-specific antibodies while only those that actually inhibit viral functions might offer protection [ 38 ].…”

“…However, the vaccines currently on the market suffer from several weaknesses. The viral surface glycoproteins (hemagglutinin and neuraminidase) regularly undergo amino acid changes that often lead to new variant strains [ 3 ]. As a result, the seasonal influenza vaccine must be reformulated and readministered on a yearly basis.…”

“…From an immunological point of view, vaccination with short and well-defined peptides may be preferential to immunizing with whole viral proteins. Since the ability to induce humoral and cellular immune responses is limited to specific regions (epitopes) within any given protein, restricting vaccine components to immulogically important epitopes could result in more focused and thus stronger cellular and humoral responses [ 3 , 5 ]. On the other hand, peptide immunogens may suffer from inherent weaknesses.…”