From new diagnostic targets to recombinant proteins and semi-synthetic protein-based vaccines

The most effective approach in controlling infectious diseases and other immune related disorders has been the development and the extensive use of preventive vaccines and vaccine therapies. However, we still need effective vaccines against some of the most threatening infectious agents. The standard costs and approaches in developing and producing a vaccine are dramatically high. In the recent past, the common effort of scientists resulted in novel approaches to vaccine target identification largely based on bioinformatics, immunoinformatics and structural biology, reducing time to identification of relevant antigens. These strategies, together with an increased knowledge of host-pathogen interactions and protection mechanisms, is enhancing the rapid development of novel vaccines. The reverse vaccinology approach also allowed the development of a large number of new recombinant protein-based vaccines. However, this approach results poorly efficient against genetically complex diseases, such as malaria, tuberculosis, HIV, and towards cancer. In the latter cases, the modern approach for designing efficient vaccines is moving to structure vaccinology. The deep characterization of different epitopes permits the rational design of new immunogenic products. For example, new products obtained by combination of differently defined antigens, such as chimeric proteins, were proposed as improved vaccines against tuberculosis. Similarly, the structural characterization of antigenic oligosaccharides allowed the development of a commercial vaccine for the prevention of Haemophilus influenzae type B. This approach has also been proposed for the treatment of other infectious diseases, such as meningococcal infections, pneumococcal infections and tuberculosis as well as for the treatment of certain types of cancer.