Session Type: ePosters
Session Title: ePosters
Authors(s): O. Pacios (1), L. Fernandez-Garcia (1), I. Bleriot (1), L. Blasco (1), A. Anton (1), M. Lopez (1), F. Fernandez-Cuenca (2), A. Pascual (2), J. Oteo (3), L. Martinez-Martinez (4), P. Domingo-Calap (5), G. Bou Arevalo (1), M. Tomás (1)
Authors Affiliations(s): (1) A Coruña Hospital (INIBIC), Spain, (2) Macarena Hospital (INIBIC), Spain, (3) CNM, Institute Salud Carlos III, Spain, (4) Reina Sofia Hospital, Spain, (5) University of Valencia, Spain
Third Party Affiliation: > 85 publications (75 first quartile) in peer-reviewed journals indexed in Web of Science,> 10,199 citations, h-factor = 31; ii) Director in 3 defended doctoral theses; currently supervises 4 PhD students at INIBIC-CHUAC; iii) 7 Projects as Principal Investigator (PI) of which 3 research projects and 4 innovation projects and iv) 3 Patents, 2 international (PCT / EP2017 / 069849 and Argentina, 19083725) and a national patent (Spain, ES2449665) . iv) Evaluator of national and international projects. In addition, she is an associate editor for international journals with high impact factor. Finally, she participates as evaluator of national research projects (Call for Strategic Health Action-ISCIII) and European ones; v) Group belongs to Spanish Infectious Diseases Networking (REIPI), directive board of Spanish Society Infections Diseases and Clinical Microbiology and, Spanish Representative from European Medical Specialities Microbiology (UEMS).
Background:
Nowadays, bacteriophages are one of the most promising alternatives to treat multi-resistant nosocomial infections. Bacteriophage cocktails have been approved by the FDA as treatments against bacterial species belonging to the ESKAPE group, such as Klebsiella pneumoniae. We analysed the infection capacity of several bacteriophages against clinical isolates of K.pneumoniae and characterized phage vB_KpM-VAC13, which has a potential therapeutic application.
Methods:Phage propagation: samples of sewage water from Valencia were cultured with each strain from our collection then reisolated to obtain pure phage cultures. All phages were propagated in LB, centrifuged, filtered through a 0.45 µm filter and stored at 4°C.
Characterization of the K. pneumoniae collection: 48 clinical strains from different human origins were sequenced, and these genomes analysed to find carbapenemases and capsular types, by analysing three different alleles.
Host-range assay: isolates of K. pneumoniae were prepared in double-agar plates, then spot tests of 47 environmental bacteriophages were done in duplicates. Plates were read after 24h of incubation at 37°C.
Characterization of the lytic phage vB_KpM-VAC13: we used the isolate K2534, well-infected by vB_KpM-VAC13, to perform infection, adsorption and one-step growth curves.
Results:
Within the K. pneumoniae collection, we observed a wide range of origins as well as multiple capsular serotypes and an extensive variety of carbapenemase presence (Table 1). The host-range assay (Figure 1) showed that 14 phages could infect ≥ 9 strains. Surprisingly, the most infective bacteriophages were able to infect 2 to 13 different capsular types. Concerning the characterization of vB_KpM-VAC13 (widest host-range), TEM showed the structure of the Myoviridae family (Figure 2c). Its time of adsorption to K2534 was estimated to be 4 min (Figure 2d), with a latent period of 15 min and a burst size of 3.21 ± 0.51 PFU per infected cell (Figure 2e).
Conclusions:These selected bacteriophages could become excellent candidates for a bacteriophage cocktail to treat multi-resistant K. pneumoniae infections, due to their extensive ability to infect pathogenic strains (9 or more) exhibiting different capsular serotypes (2 to 13 different capsular types).
Lytic phage vB_KpM-VAC13 showed a remarkably broad spectrum against K. pneumoniae clinical strains.
Session Type: ePosters
Session Title: ePosters
Authors(s): O. Pacios (1), L. Fernandez-Garcia (1), I. Bleriot (1), L. Blasco (1), A. Anton (1), M. Lopez (1), F. Fernandez-Cuenca (2), A. Pascual (2), J. Oteo (3), L. Martinez-Martinez (4), P. Domingo-Calap (5), G. Bou Arevalo (1), M. Tomás (1)
Authors Affiliations(s): (1) A Coruña Hospital (INIBIC), Spain, (2) Macarena Hospital (INIBIC), Spain, (3) CNM, Institute Salud Carlos III, Spain, (4) Reina Sofia Hospital, Spain, (5) University of Valencia, Spain
Third Party Affiliation: > 85 publications (75 first quartile) in peer-reviewed journals indexed in Web of Science,> 10,199 citations, h-factor = 31; ii) Director in 3 defended doctoral theses; currently supervises 4 PhD students at INIBIC-CHUAC; iii) 7 Projects as Principal Investigator (PI) of which 3 research projects and 4 innovation projects and iv) 3 Patents, 2 international (PCT / EP2017 / 069849 and Argentina, 19083725) and a national patent (Spain, ES2449665) . iv) Evaluator of national and international projects. In addition, she is an associate editor for international journals with high impact factor. Finally, she participates as evaluator of national research projects (Call for Strategic Health Action-ISCIII) and European ones; v) Group belongs to Spanish Infectious Diseases Networking (REIPI), directive board of Spanish Society Infections Diseases and Clinical Microbiology and, Spanish Representative from European Medical Specialities Microbiology (UEMS).
Background:
Nowadays, bacteriophages are one of the most promising alternatives to treat multi-resistant nosocomial infections. Bacteriophage cocktails have been approved by the FDA as treatments against bacterial species belonging to the ESKAPE group, such as Klebsiella pneumoniae. We analysed the infection capacity of several bacteriophages against clinical isolates of K.pneumoniae and characterized phage vB_KpM-VAC13, which has a potential therapeutic application.
Methods:Phage propagation: samples of sewage water from Valencia were cultured with each strain from our collection then reisolated to obtain pure phage cultures. All phages were propagated in LB, centrifuged, filtered through a 0.45 µm filter and stored at 4°C.
Characterization of the K. pneumoniae collection: 48 clinical strains from different human origins were sequenced, and these genomes analysed to find carbapenemases and capsular types, by analysing three different alleles.
Host-range assay: isolates of K. pneumoniae were prepared in double-agar plates, then spot tests of 47 environmental bacteriophages were done in duplicates. Plates were read after 24h of incubation at 37°C.
Characterization of the lytic phage vB_KpM-VAC13: we used the isolate K2534, well-infected by vB_KpM-VAC13, to perform infection, adsorption and one-step growth curves.
Results:
Within the K. pneumoniae collection, we observed a wide range of origins as well as multiple capsular serotypes and an extensive variety of carbapenemase presence (Table 1). The host-range assay (Figure 1) showed that 14 phages could infect ≥ 9 strains. Surprisingly, the most infective bacteriophages were able to infect 2 to 13 different capsular types. Concerning the characterization of vB_KpM-VAC13 (widest host-range), TEM showed the structure of the Myoviridae family (Figure 2c). Its time of adsorption to K2534 was estimated to be 4 min (Figure 2d), with a latent period of 15 min and a burst size of 3.21 ± 0.51 PFU per infected cell (Figure 2e).
Conclusions:These selected bacteriophages could become excellent candidates for a bacteriophage cocktail to treat multi-resistant K. pneumoniae infections, due to their extensive ability to infect pathogenic strains (9 or more) exhibiting different capsular serotypes (2 to 13 different capsular types).
Lytic phage vB_KpM-VAC13 showed a remarkably broad spectrum against K. pneumoniae clinical strains.