Abstract
Designing potent therapeutic cocktails using the naturally occurring bacteriophage grouping model
Glonti, Tea 1, PIRNAY, Jean-Paul 1
1Laboratory for Molecular and Cellular Technology, Queen Astrid Military Hospital, Brussels, Belgium
Background. The specificity of phages and their ability to evolve and overcome bacterial resistance make them potentially useful as adjuncts in the treatment of antibiotic-resistant bacterial infections. This work aims to mimic the natural grouping of phages of interest and to demonstrate the mode of their proliferation dynamics with bacteria: synergy, proto-cooperation, or antagonism.
Materials and methods. The phage lytic activities both individually (n = 27) and in 14 different cocktails on planktonic bacterial cultures was assayed, using a large collection of P. aeruginosa (n = 102) and K. pneumoniae (n = 155) strains carrying different virulence factors and phage binding receptors. An interpretation model curve for phage liquid culturing was introduced, which allowed easy and quick analysis of bacterial and phage co-proliferation and growth of phage-resistant mutants (PRM) based on qualitative and partially quantitative evaluations.
Results and conclusions.
The naturally occurring phage groups were directly transferred from isolation sources to in vitro for the first time and identified 13 P. aeruginosa and 11 K. pneumoniae phages from 18 different genera with host ranges of 1.2–17%, 28–48% and 60–87%, including resistotypes of P. aeruginosa (PAO1, PA14 and PA7) and seven K. pneumoniae strains of different capsular serotypes.
Based on the results, the natural phage cocktails designed and tested in this study generally performed well and inhibited PRM growth either synergistically or in proto-cooperation. The approach of using a bacterial panel of relevant diversity to assess phage virulence with respect to antibiotic-resistant strains and PRM emergence was shown to facilitate the evaluation and differentiation of the therapeutic potential of individual phages and phage cocktails.
The data demonstrated the advantage of phage bi- and tri-cocktails composed of the different genera over single phages in controlling PRM growth in vitro, and it was found that phages are better “trained” in natural river water than in urban/hospital sewage water. This study contributes to the knowledge of phage behavior in cocktails and the formulation of therapeutic phage preparations.
Glonti, Tea 1, PIRNAY, Jean-Paul 1
1Laboratory for Molecular and Cellular Technology, Queen Astrid Military Hospital, Brussels, Belgium
Background. The specificity of phages and their ability to evolve and overcome bacterial resistance make them potentially useful as adjuncts in the treatment of antibiotic-resistant bacterial infections. This work aims to mimic the natural grouping of phages of interest and to demonstrate the mode of their proliferation dynamics with bacteria: synergy, proto-cooperation, or antagonism.
Materials and methods. The phage lytic activities both individually (n = 27) and in 14 different cocktails on planktonic bacterial cultures was assayed, using a large collection of P. aeruginosa (n = 102) and K. pneumoniae (n = 155) strains carrying different virulence factors and phage binding receptors. An interpretation model curve for phage liquid culturing was introduced, which allowed easy and quick analysis of bacterial and phage co-proliferation and growth of phage-resistant mutants (PRM) based on qualitative and partially quantitative evaluations.
Results and conclusions.
The naturally occurring phage groups were directly transferred from isolation sources to in vitro for the first time and identified 13 P. aeruginosa and 11 K. pneumoniae phages from 18 different genera with host ranges of 1.2–17%, 28–48% and 60–87%, including resistotypes of P. aeruginosa (PAO1, PA14 and PA7) and seven K. pneumoniae strains of different capsular serotypes.
Based on the results, the natural phage cocktails designed and tested in this study generally performed well and inhibited PRM growth either synergistically or in proto-cooperation. The approach of using a bacterial panel of relevant diversity to assess phage virulence with respect to antibiotic-resistant strains and PRM emergence was shown to facilitate the evaluation and differentiation of the therapeutic potential of individual phages and phage cocktails.
The data demonstrated the advantage of phage bi- and tri-cocktails composed of the different genera over single phages in controlling PRM growth in vitro, and it was found that phages are better “trained” in natural river water than in urban/hospital sewage water. This study contributes to the knowledge of phage behavior in cocktails and the formulation of therapeutic phage preparations.
| Original language | English |
|---|---|
| Title of host publication | 3rd BSVoM symposium in Brussels |
| Publication status | Published - 6 Sept 2024 |