**1. Introduction**

652 Biomedical Science, Engineering and Technology

Zhu, Q., Liang, S., Martin, L., Gasparini, S., Menez, A.&Vita, C. (2002) Role of Disulfide

Zhu, S., Gao, B.&Tytgat, J. (2005) Phylogenetic distribution, functional epitopes and

Zunino, P., D'Angelo, C., Petrini, L., Vergara, C., Capelli, C.&Migliavacca, F. (2009)

*Biochemistry* Vol. 41 No. 38 pp. 11488-11494


No. 45-46 pp. 3633-3644

Bonds in Folding and Activity of Leiurotoxin I: Just Two Disulfides Suffice

evolution of the CSαβ superfamily *Cellular and Molecular Life Sciences* Vol. 62 No. 19

Numerical simulation of drug eluting coronary stents: Mechanics, fluid dynamics and drug release *Computer Methods in Applied Mechanics and Engineering* Vol. 198

> Vaccinology as a scientific field is undergoing a dramatic development. Never before such sophisticated techniques and in-depth knowledge of immunological processes have been at hand to exploit fully the potential of protecting from as well as curing diseases through vaccination. In spite of great successes like eradication of smallpox in the 1970s and poliomyelitis elimination from all but six countries in the world (two important milestones in the medical history), new challenges have arisen to be faced. Rapidly changing ecosystems and human behaviour, an ever-increasing density of human and farmed animal populations, a high degree of mobility resulting in rapid spreading of pathogens in infected people and animals, new contacts between human and animals in endemic areas, poverty, and war conflicts in the third world, and many other factors contribute to the more frequent occurrence and rapid dissemination of new diseases. Three diseases that most heavily afflict global health are AIDS, tuberculosis, and malaria. As an example of new viral pathogens we can mention Ebola virus, SARS-coronavirus, or new strains of influenza virus (Wack & Rappuoli, 2005).

> Among re-emerging diseases of the past few years, diphteria and cholera should be mentioned. Moreover, multi drug-resistant bacteria frequently occur as a result of overdosing on antibiotics. One of the most important future challenges will be to respond promptly to emerging diseases such as those mentioned above. Rapid sequencing of the genome of the pathogen implicated the speed of the development of diagnostic tools as well as the identification and expression of recombinant targets for vaccines and therapeutic agents development (Stadler et al., 2003). Immunotherapy of cancer represents a special field, where anticancer vaccines could be powerful weapons/tools for long-term effective treatment.

> The progress in the vaccine development is closely related with the progress in immunology and molecular biology. A new term "Reverse vaccinology" was proposed by Rappuoli (Rappuoli, 2000) to specify a complex genome-based approach in the vaccine development. Unlike the conventional approach that requires a laborious process of a selection of individual components important for the induction of protective immune response, reverse vaccinology offers a possibility to use genomic information derived from *in silico* analysis of the sequenced organisms. This approach can significantly reduce the time necessary to identify the antigens for the development of a candidate vaccine and enables a systematic identification of all potential antigens of pathogens including those which are difficult or

currently impossible to culture. Of course, this approach is limited to the identification of protein or glycoprotein antigens, omitting such important vaccine components as polysaccharides and glycolipids. Nevertheless, reverse vaccinology can enable scientists to systemically classify the potential protective antigens, thereby helping to improve the existing vaccines and to develop efficient preparations against virtually any pathogen that has had its genome sequence determined.

As regards the process of activation of the immune system to produce an adaptive immune response, it is generally observed that the antigen by itself may not be adequate as a stimulating agent. Many potential antigens have no apparent immunizing activity at all when tested alone. In general, seamy side of pure recombinant protein antigens and synthetic peptide antigens is their poor immunogenicity. Therefore, potent adjuvants are required for highly purified antigen-based vaccines to be effective.
