Fachbereich Veterinärmedizin



    Localization and Pneumococcal Alteration of Junction Proteins in the Human Alveolar-Capillary Compartment (2017)

    Zeitschriftenartikel / wissenschaftlicher Beitrag
    Peter, Andrea
    Fatykhova, Diana
    Kershaw, Olivia (WE 12)
    Gruber, Achim D (WE 12)
    Rueckert, Jens
    Neudecker, Jens
    Toennies, Mario
    Bauer, Torsten T
    Schneider, Paul
    Schimek, Maria
    Eggeling, Stephan
    Suttorp, Norbert
    Hocke, Andreas C
    Hippenstiel, Stefan
    Histochemistry and cell biology; 147(6) — S. 707–719
    ISSN: 0948-6143
    DOI: 10.1007/s00418-017-1551-y
    Pubmed: 28247028
    Institut für Tierpathologie

    Robert-von-Ostertag-Str. 15
    Gebäude 12
    14163 Berlin
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    Abstract / Zusammenfassung

    Loss of alveolar barrier function with subsequent respiratory failure is a hallmark of severe pneumonia. Although junctions between endo- and epithelial cells regulate paracellular fluid flux, little is known about their composition and regulation in the human alveolar compartment. High autofluorescence of human lung tissue in particular complicates the determination of subcellular protein localization. By comparing conventional channel mode confocal imaging with spectral imaging and linear unmixing, we demonstrate that background fluorescent spectra and fluorophore signals could be rigorously separated resulting in complete recovery of the specific signal at a high signal-to-noise ratio. Using this technique and Western blotting, we show the expression patterns of tight junction proteins occludin, ZO-1 as well as claudin-3, -4, -5 and -18 and adherence junction protein VE-cadherin in naive or Streptococcus pneumoniae-infected human lung tissue. In uninfected tissues, occludin and ZO-1 formed band-like structures in alveolar epithelial cells type I (AEC I), alveolar epithelial cells type II (AEC II) and lung capillaries, whereas claudin-3, -4 and -18 were visualised in AEC II. Claudin-5 was detected in the endothelium only. Claudin-3, -5, -18 displayed continuous band-like structures, while claudin-4 showed a dot-like expression. Pneumococcal infection reduced alveolar occludin, ZO-1, claudin-5 and VE-cadherin but did not change the presence of claudin-3, -4 and -18. Spectral confocal microscopy allows for the subcellular structural analysis of proteins in highly autofluorescent human lung tissue. The thereby observed deterioration of lung alveolar junctional organisation gives a structural explanation for alveolar barrier disruption in severe pneumococcal pneumonia.