Quantifying heterogeneity: flow cytometry of bacterial cultures

Feasibility of disinfection kinetics and minimum inhibitory concentration determination on bacterial cultures using flow cytometry

Water Science & Technology ◽

10.2166/wst.2008.619 ◽

2008 ◽

Vol 58 (4) ◽

pp. 937-944 ◽

Cited By ~ 6

Author(s):

J. H. Cunningham ◽

C. Cunningham ◽

B. Van Aken ◽

L.-S. Lin

Keyword(s):

Escherichia Coli ◽

Flow Cytometry ◽

Minimum Inhibitory Concentration ◽

Antimicrobial Agents ◽

Inhibitory Concentration ◽

Microbial Consortium ◽

Silver Ion ◽

Single Type ◽

Physiological Status ◽

Bacterial Cultures

Disinfection kinetics has been well established for selected antimicrobial agents on isolated bacterial strains. Due to the difficulties of culturing most bacteria, the majority of these studies have been limited to readily cultivable microorganisms of a single type or family. This study explores the feasibility of using flow cytometry for characterising the disinfection kinetics and minimum inhibitory concentration (MIC) of an Escherichia coli culture and a microbial consortium. The proposed method relies on fluorescent dye molecules to indicate the morphological and physiological status of numerous individual cells. Biocides of varying effectiveness and inactivation mechanisms (chlorine, iodine, and silver) were used to evaluate this novel application. Using pseudo-first-order kinetics, the coefficients of specific lethality of chlorine and iodine on Escherichia coli were 4.71 and 3.78×10−3 L mg−1 min−1 and MIC of silver ion was between 60 and 80 μg L−1. The coefficients of specific lethality of chlorine and iodine on the microbial consortium were 4.96 and 8.89×10−3 L mg−1 min−1 and MIC of silver ion was between 40 and 60 μg L−1. This method can be used to provide a rapid and consistent way of determining disinfection kinetics and MICs for pure and mixed bacterial cultures and can potentially be used to examine water and wastewater disinfection efficiency. However, caution should be used to ensure that the physiological and morphological status characterised by cytodyes is a result of the inactivation mechanisms of the disinfectants evaluated.

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Detection of Sulfur Microparticles in Bacterial Cultures by Flow Cytometry

Engineering in Life Sciences ◽

10.1002/elsc.200720195 ◽

2007 ◽

Vol 7 (4) ◽

pp. 403-407 ◽

Cited By ~ 9

Author(s):

T. Hübschmann ◽

C. Vogt ◽

S. Till ◽

T. Rohwerder ◽

W. Sand ◽

...

Keyword(s):

Flow Cytometry ◽

Bacterial Cultures

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Multicentric experience with interferon gamma therapy in sepsis induced immunosuppression. A case series

BMC Infectious Diseases ◽

10.1186/s12879-019-4526-x ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 22

Author(s):

Didier Payen ◽

Valerie Faivre ◽

Jordi Miatello ◽

Jenneke Leentjens ◽

Caren Brumpt ◽

...

Keyword(s):

Flow Cytometry ◽

Interferon Gamma ◽

Plasma Levels ◽

Case Series ◽

Optimal Timing ◽

Hemorrhagic Complication ◽

Bacterial Cultures ◽

Adaptive Immune Cells ◽

Potential Clinical Benefit ◽

Hla Dr

Abstract Background The sepsis-induced immunodepression contributes to impaired clinical outcomes of various stress conditions. This syndrome is well documented and characterized by attenuated function of innate and adaptive immune cells. Several pharmacological interventions aimed to restore the immune response are emerging of which interferon-gamma (IFNγ) is one. It is of paramount relevance to obtain clinical information on optimal timing of the IFNγ-treatment, −tolerance, −effectiveness and outcome before performing a RCT. We describe the effects of IFNγ in a cohort of 18 adult and 2 pediatric sepsis patients. Methods In this open-label prospective multi-center case-series, IFNγ treatment was initiated in patients selected on clinical and immunological criteria early (< 4 days) or late (> 7 days) following the onset of sepsis. The data collected in 18 adults and 2 liver transplanted pediatric patients were: clinical scores, monocyte expression of HLA-DR (flow cytometry), lymphocyte immune-phenotyping (flow cytometry), IL-6 and IL-10 plasma levels (ELISA), bacterial cultures, disease severity, and mortality. Results In 15 out of 18 patients IFNγ treatment was associated with an increase of median HLA-DR expression from 2666 [IQ 1547; 4991] to 12,451 [IQ 4166; 19,707], while the absolute number of lymphocyte subpopulations were not affected, except for the decrease number of NK cells 94.5 [23; 136] to 32.5 [13; 90.8] (0.0625)]. Plasma levels of IL-6 464 [201–770] to 108 (89–140) ng/mL (p = 0.04) and IL-10 from IL-10 from 29 [12–59] to 9 [1–15] pg/mL decreased significantly. Three patients who received IFNγ early after ICU admission (<4 days) died. The other patients had a rapid clinical improvement assessed by the SOFA score and bacterial cultures that were repeatedly positive became negative. The 2 pediatric cases improved rapidly, but 1 died for hemorrhagic complication. Conclusion Guided by clinical and immunological monitoring, adjunctive immunotherapy with IFNγ appears well-tolerated in our cases and improves immune host defense in sepsis induced immuno suppression. Randomized clinical studies to assess its potential clinical benefit are warranted.

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