FITC-albumin as a marker for assessment of endothelial permeability in mice: comparison with 125I-albumin.
Transvascular transport of labeled-albumin is used to study endothelial permeability in experimental murine models of pulmonary infections. But radio-tagged albumin necessitates heavy safety procedures in terms of storage, manipulation and evacuation. The authors tested fluorescein isothiocyanate-tagged albumin (FITC-albumin) as a new marker for determination of endothelial permeability in a murine model of lung infection by Pseudomonas aeruginosa PAO1, in comparison with a standard method with (125)I-albumin. The mean permeability +/- SEM measured with (125)I-albumin was 2.45%/2 h +/- 0.37 for the control mice and 6.65%/2 h +/- 0.77 for the infected ones (P < .0001). With FITC-albumin, results obtained for both groups were respectively 4.96%/2 h +/- 0.64 and 11.5%/2 h +/- 1.2 (P < .0001). Spearman's rank coefficient was equal to .88 (P < .0001), showing a very strong correlation between both methods of measurement. The Bland-Altman analysis of bias revealed that there was no significant bias between FITC-albumin-derived and (125)I-albumin-derived values. The correction of the values obtained in plasma and lung homogenate supernatants by the subtraction of natural spontaneous fluorescence measured in these samples was crucial for the calculation of endothelial permeability in this new method. We believe that FITC-albumin can be useful for assessment of endothelial permeability in murine models of pulmonary diseases.
Faculté de Medecine, Thérapeutiques Cliniques et Expérimentales des Infections, Université de Nantes, Nantes, France. david.boutoille1@aliceadsl.fr
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D
Boutoille
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Marechal
Marie
M
Pichenot
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C
Chemani
B
B
Guery
K
K
Faure
D000818:Animals; D002199:Capillary Permeability; D004730:Endothelium, Vascular / Q000378:metabolism*; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D007457:Iodine Radioisotopes / Q000493:pharmacokinetics; D008722:Methods; D051379:Mice; D011550:Pseudomonas aeruginosa; D015203:Reproducibility of Results; D012141:Respiratory Tract Infections / Q000175:diagnosis / Q000473:pathology; D012709:Serum Albumin / Q000493:pharmacokinetics
C518288:FITC-albumin; D007457:Iodine Radioisotopes; D012709:Serum Albumin; D016650:Fluorescein-5-isothiocyanate