216
the pathogenesis involves the dysregulation of protein expression (Chan et al. 2006).
The routes of antisense oligonucleotides administration are local (or topical) and
parenteral. When they are administered for systemic application, the parenteral
injection is preferred either intravenously or subcutaneously. No significant changes
are observed in the bioavailability between the intravenous and subcutaneous routes
of administration (Geary 2009).
9.7 Antibacterial Drug Discovery Based on Phage Therapies
An alternative method to control bacterial infections is the use of bacteriophages.
Bacteriophages are viruses that can infect bacteria. In that way, they express their
unique anti bacterial property. Their use in medicine is dated since 1919 hence,
before the discovery of the first antibiotics. Twort and d’Herele discovered the first
phages in 1915 and 1917. However, with the discovery of antibiotics, and particularly after the Second World War, antibiotics, especially in Western countries,
replaced phage therapies (Bassetti et al. 2017). However, in some countries, including Poland, Russia, and Georgia, the use of phages remained a popular treatment
strategy throughout the twentieth century and even up to present days. Bacteriophages
are present almost in all the ecosystems including the human body and even in
extreme environments. They are capable to fight antibacterial infections when they
are applied in addition to antibiotics or as an alternative to antibiotic therapies. The
overuse along with the misuse of antibiotics globally leads to the rapid development
of antimicrobial resistance, which is a great threat to public health with serious
socio economic impacts. The need for new alternative treatments against drug resistant strains is inevitable. There is no doubt that phage therapies consist of an
unavoidable option for research and they seem to be a promising therapeutic strategy in cases where resistant bacterial strains have already developed and antibiotics
are not effective anymore. Nevertheless, more researches should be done in this
field. There is a great need of scientists to improve their knowledge on the subject
of phages to be able to understand their biology to ensure the best conditions during
their preparation and render their use against bacteria a successful strategy to fight
antimicrobial resistance development (Mantravadi et al. 2019).
Bacteriophages have some special characteristics. The genomic plasticity and
rapid replication are two characteristics of great importance. Some point mutations,
rearrangements at the level of the genome and their capacity to exchange genetic
material are some of the causes of their great diversity. The use of bacteriophages as
therapeutic particles seems to have many advantages. At first, they are very specific.
Every phage is capable of recognizing a particular ligand on the cell wall. The
ligand that is recognized turns to be specific for a certain bacterial strain. Thus, a
phage affects only a particular strain and is not capable to harm other strains. In this
way, phages are not able to select resistance in other strains but only to the strains
that they target. Bacteria can also develop resistance against phages but in comparison to antibiotics, phages can evolve it. Thus, the development of resistance will not
A. Valsamatzi-Panagiotou et al.
the pathogenesis involves the dysregulation of protein expression (Chan et al. 2006).
The routes of antisense oligonucleotides administration are local (or topical) and
parenteral. When they are administered for systemic application, the parenteral
injection is preferred either intravenously or subcutaneously. No significant changes
are observed in the bioavailability between the intravenous and subcutaneous routes
of administration (Geary 2009).
9.7 Antibacterial Drug Discovery Based on Phage Therapies
An alternative method to control bacterial infections is the use of bacteriophages.
Bacteriophages are viruses that can infect bacteria. In that way, they express their
unique anti bacterial property. Their use in medicine is dated since 1919 hence,
before the discovery of the first antibiotics. Twort and d’Herele discovered the first
phages in 1915 and 1917. However, with the discovery of antibiotics, and particularly after the Second World War, antibiotics, especially in Western countries,
replaced phage therapies (Bassetti et al. 2017). However, in some countries, including Poland, Russia, and Georgia, the use of phages remained a popular treatment
strategy throughout the twentieth century and even up to present days. Bacteriophages
are present almost in all the ecosystems including the human body and even in
extreme environments. They are capable to fight antibacterial infections when they
are applied in addition to antibiotics or as an alternative to antibiotic therapies. The
overuse along with the misuse of antibiotics globally leads to the rapid development
of antimicrobial resistance, which is a great threat to public health with serious
socio economic impacts. The need for new alternative treatments against drug resistant strains is inevitable. There is no doubt that phage therapies consist of an
unavoidable option for research and they seem to be a promising therapeutic strategy in cases where resistant bacterial strains have already developed and antibiotics
are not effective anymore. Nevertheless, more researches should be done in this
field. There is a great need of scientists to improve their knowledge on the subject
of phages to be able to understand their biology to ensure the best conditions during
their preparation and render their use against bacteria a successful strategy to fight
antimicrobial resistance development (Mantravadi et al. 2019).
Bacteriophages have some special characteristics. The genomic plasticity and
rapid replication are two characteristics of great importance. Some point mutations,
rearrangements at the level of the genome and their capacity to exchange genetic
material are some of the causes of their great diversity. The use of bacteriophages as
therapeutic particles seems to have many advantages. At first, they are very specific.
Every phage is capable of recognizing a particular ligand on the cell wall. The
ligand that is recognized turns to be specific for a certain bacterial strain. Thus, a
phage affects only a particular strain and is not capable to harm other strains. In this
way, phages are not able to select resistance in other strains but only to the strains
that they target. Bacteria can also develop resistance against phages but in comparison to antibiotics, phages can evolve it. Thus, the development of resistance will not
A. Valsamatzi-Panagiotou et al.