TY - JOUR
T1 - Simple fluorometric-based assay of antibiotic effectiveness for Acinetobacter baumannii biofilms
AU - Wannigama, Dhammika Leshan
AU - Hurst, Cameron
AU - Pearson, Lachlan
AU - Saethang, Thammakorn
AU - Singkham-in, Uthaibhorn
AU - Luk-in, Sirirat
AU - Storer, Robin James
AU - Chatsuwan, Tanittha
N1 - Funding Information:
This work was supported by a grant from the 90th Year Anniversary Ratchadapiseksompotch Endowment Fund from the Faculty of Medicine and Graduate School, Chulalongkorn University (batch No. 39 (2/61)), Ratchadapiseksompotch Fund, Faculty of Medicine, Chulalongkorn University Bangkok, Thailand (grant No. RA62/013). Dhammika Leshan Wannigama was supported under the 100th Anniversary Chulalongkorn University Fund for Doctoral Scholarships, The University of Western Australia for Cross institutional exchange Doctoral fellowship and Graduate School, Chulalongkorn University, for Overseas Research Experience Scholarship.
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Despite strengthened antimicrobial therapy, biofilm infections of Acinetobacter baumannii are associated with poor prognosis and limited therapeutic options. Assessing antibiotics on planktonic bacteria can result in failure against biofilm infections. Currently, antibiotics to treat biofilm infections are administered empirically, usually without considering the susceptibility of the biofilm objectively before beginning treatment. For effective therapy to resolve biofilm infections it is essential to assess the efficacy of commonly used antibiotics against biofilms. Here, we offer a robust and simple assay to assess the efficacy of antibiotics against biofilms. In the present work, we carefully optimized the incubation time, detection range, and fluorescence reading mode for resazurin-based viability staining of biofilms in 96-well-plates and determined minimal biofilm eradication concentrations (MBECs) for A. baumannii isolates from patients with chronic infection. By applying this assay, we demonstrated that antibiotic response patterns varied uniquely within the biofilm formation of various clinical samples. MBEC-50 and 75 have significant discriminatory power over minimum inhibitory concentrations for planktonic suspensions to differentiate the overall efficiency of an antibiotic to eradicate a biofilm. The present assay is an ideal platform on which to assess the efficacy of antibiotics against biofilms in vitro to pave the way for more effective therapy.
AB - Despite strengthened antimicrobial therapy, biofilm infections of Acinetobacter baumannii are associated with poor prognosis and limited therapeutic options. Assessing antibiotics on planktonic bacteria can result in failure against biofilm infections. Currently, antibiotics to treat biofilm infections are administered empirically, usually without considering the susceptibility of the biofilm objectively before beginning treatment. For effective therapy to resolve biofilm infections it is essential to assess the efficacy of commonly used antibiotics against biofilms. Here, we offer a robust and simple assay to assess the efficacy of antibiotics against biofilms. In the present work, we carefully optimized the incubation time, detection range, and fluorescence reading mode for resazurin-based viability staining of biofilms in 96-well-plates and determined minimal biofilm eradication concentrations (MBECs) for A. baumannii isolates from patients with chronic infection. By applying this assay, we demonstrated that antibiotic response patterns varied uniquely within the biofilm formation of various clinical samples. MBEC-50 and 75 have significant discriminatory power over minimum inhibitory concentrations for planktonic suspensions to differentiate the overall efficiency of an antibiotic to eradicate a biofilm. The present assay is an ideal platform on which to assess the efficacy of antibiotics against biofilms in vitro to pave the way for more effective therapy.
UR - http://www.scopus.com/inward/record.url?scp=85064563938&partnerID=8YFLogxK
U2 - 10.1038/s41598-019-42353-0
DO - 10.1038/s41598-019-42353-0
M3 - Article
C2 - 31004100
AN - SCOPUS:85064563938
VL - 9
SP - 1
EP - 14
JO - Scientific Reports
JF - Scientific Reports
SN - 2045-2322
IS - 1
M1 - 6300
ER -