- Birgitta Duim (1)
- B. Duim (2)
- A.C. Fluit (2)
- M.J. Jonker (1)
- Koen M. Verstappen (1)
- D. Mevius (1)
- D.J. Mevius (1)
- Arie Nes Van (1)
- J.P. Putten van (1)
- Pawel Tulinski (1)
- P. Tulinski (3)
- C. Verwer (1)
- L.P.L. Vijver van de (2)
- J.A. Wagenaar (2)
- F.R. Wittink (1)
The effectiveness of bacteriophages against methicillin-resistant Staphylococcus aureus ST398 nasal colonization in pigs
Verstappen, Koen M. ; Tulinski, Pawel ; Duim, Birgitta ; Fluit, Ad C. ; Carney, Jennifer ; Nes, Arie Van; Wagenaar, Jaap A. - \ 2016
PLoS One 11 (2016)8. - ISSN 1932-6203
Methicillin-resistant Staphylococcus aureus (MRSA) is an important colonizer in animals and an opportunistic pathogen in humans. In humans, MRSA can cause infections that might be difficult to treat because of antimicrobial resistance. The use of bacteriophages has been suggested as a potential approach for the control of MRSA colonization to minimize the - often occupational - exposure of humans. The aim of this study was to assess the efficacy of bacteriophage treatment on porcine nasal colonization with MRSA in vitro, in vivo, and ex vivo. The effectiveness of a bacteriophage combination of phage K∗710 and P68 was assessed in vitro by incubating them with MRSA V0608892/1 (ST398) measuring the OD600 hourly. To study the in vivo effect, bacteriophages were administered in a gel developed for human application, which contain 109 plaque-forming units (pfu)/mL (K and P68 in a 19.25:1 ratio) for 5 days to piglets (N = 8) that were experimentally colonized with the MRSA strain. Eight piglets experimentally colonized were used as a negative control. The MRSA strain was also used to colonize porcine nasal mucosa explants and bacteriophages were applied to assess the ex vivo efficacy of treatment. Bacteriophages were effective in vitro. In vivo, sixteen piglets were colonized with MRSA but the number of CFU recovered after the application of the bacteriophages in 8 piglets was not reduced compared to the control animals (approx. 105 CFU/swab). In the ex vivo model, 108 CFU were used to establish colonization with MRSA; a reduction of colonization was not observed after application of bacteriophages. However, application of mupirocin both in vivo and ex vivo resulted in a near eradication of MRSA. In conclusion: i) The MRSA strain was killed in the presence of the bacteriophages phage K∗710 and P68 in vitro. ii) Bacteriophages did not reduce porcine nasal colonization in vivo or ex vivo. Physiological in vivo and ex vivo conditions may explain these observations. Efficacy in the ex vivo model matched that of the in vivo system.
Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium
Tulinski, P. ; Duim, B. ; Wittink, F.R. ; Jonker, M.J. ; Breit, T.M. ; Putten, J.P. van; Wagenaar, J.A. ; Fluit, A.C. - \ 2014
BMC Genomics 15 (2014). - ISSN 1471-2164
clumping factor-b - methicillin-resistant - carriage - model - adherence - humans - proteinases - determinant - infections - cells
Background: Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig colonization by MRSA ST398 is poorly understood. Previously, we developed a nasal colonization model of porcine nasal mucosa explants to identify molecular traits involved in nasal MRSA colonization of pigs. Results: We report the analysis of changes in the transcription of MRSA ST398 strain S0462 during colonization on the explant epithelium. Major regulated genes were encoding metabolic processes and regulation of these genes may represent metabolic adaptation to nasal mucosa explants. Colonization was not accompanied by significant changes in transcripts of the main virulence associated genes or known human colonization factors. Here, we documented regulation of two genes which have potential influence on S. aureus colonization; cysteine extracellular proteinase (scpA) and von Willebrand factor-binding protein (vWbp, encoded on SaPIbov5). Colonization with isogenic-deletion strains (Delta vwbp and Delta scpA) did not alter the ex vivo nasal S. aureus colonization compared to wild type. Conclusions: Our results suggest that nasal colonization with MRSA ST398 is a complex event that is accompanied with changes in bacterial gene expression regulation and metabolic adaptation.
Prevalence and molecular characteristics of Methicillin-Resistant Staphylococcus aureus (MRSA) in organic pig herds in The Netherlands
Bondt, N. ; Vijver, L.P.L. van de; Tulinski, P. ; Mevius, D. ; Verwer, C. - \ 2014
Zoonoses and Public Health (2014). - ISSN 1863-1959
livestock-associated mrsa - sequence type 398 - transmission - strains - farms
The prevalence of the methicillin-resistant Staphylococcus aureus (MRSA) among conventional pig herds in the Netherlands is high (around 71%). Nevertheless, information about the prevalence of MRSA among organic pig herds is lacking. Here, we report a study on 24 of the 49 organic pig herds in the Netherlands. The prevalence of MRSA positive herds showed to be 21%. The genetic characteristics of the MRSA isolates were similar to MRSA CC398 described in conventional pigs except one exceptional HA-MRSA CC30 found in one herd, which was presumably caused by human to animal transmission. This resulted in a prevalence of MRSA CC398 in the organic herds of 16.7%.
Methicillin resistant coagulase-negative staphylococci on pig farms and as a reservoir of heterogeneous staphylococcal casette chromosome mec elements
Tulinski, P. ; Fluit, A.C. ; Wagenaar, J.A. ; Mevius, D.J. ; Vijver, L.P.L. van de; Duim, B. - \ 2012
Applied and Environmental Microbiology 78 (2012)2. - ISSN 0099-2240 - p. 299 - 304.
aureus - sccmec - strains - susceptibility - identification - diversity - evolution - region - sentry - pcr
Methicillin-resistant Staphylococcus aureus (MRSA) likely originated by acquisition of the staphylococcal cassette chromosome mec (SCCmec) from coagulase-negative staphylococci (CNS). However, it is unknown whether the same SCCmec types are present in MRSA and CNS that reside in the same niche. Here we describe a study to determine the presence of a potential mecA reservoir among CNS recovered from 10 pig farms. The 44 strains belonged to 10 different Staphylococcus species. All S. aureus strains belonged to sequence type 398 (ST398), with SCCmec types V and IVa. Type IVc, as well as types III and VI, novel subtypes of type IV, and not-typeable types, were found in CNS. S. aureus, S. epidermidis, and S. haemolyticus shared SCCmec type V. The presence of SCCmec type IVc in several staphylococcal species isolated from one pig farm is noteworthy, suggesting exchange of this SCCmec type in CNS, but the general distribution of this SCCmec type still has to be established. In conclusion, this study shows that SCCmec types among staphylococcal species on pig farms are heterogeneous. On two farms, more than one recovered staphylococcal species harbored the same SCCmec type. We conclude that staphylococci on pig farms act as a reservoir of heterogeneous SCCmec elements. These staphylococci may act as a source for transfer of SCCmec to S. aureus.