Beschreibung:
<jats:title>Abstract</jats:title>
<jats:sec>
<jats:title>Background</jats:title>
<jats:p>The cell invasiveness of <jats:italic>Mycoplasma gallisepticum,</jats:italic> the causative agent of respiratory disease in chickens and infectious sinusitis in turkeys, may be a substantial factor in the well-known chronicity of these diseases and in the systemic spread of infection. To date, not much is known about the host factors and mechanisms involved in promotion or obstruction of <jats:italic>M. gallisepticum</jats:italic> adherence and/or cell invasion.</jats:p>
<jats:p>In the current study, the influence of extracellular matrix (ECM) proteins such as fibronectin, collagen type IV and heparin, as well as plasminogen/plasmin, on the adhesion and cell invasion levels of <jats:italic>M. gallisepticum</jats:italic> to chicken erythrocytes and HeLa cells was investigated <jats:italic>in vitro</jats:italic>. Two strains, R<jats:sub>high</jats:sub> and R<jats:sub>low,</jats:sub> which differ in their adhesion and invasion capacity, were analyzed by applying a modified gentamicin invasion assay. Binding of selected ECM molecules to <jats:italic>M. gallisepticum</jats:italic> was proven by Western blot analysis.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Results</jats:title>
<jats:p>Collagen type IV, fibronectin, and plasminogen exerted positive effects on adhesion and cell invasion of <jats:italic>M. gallisepticum,</jats:italic> with varying degrees, depending on the strain used. Especially strain R<jats:sub>high</jats:sub>, with its highly reduced cell adhesion and invasion capabilities seemed to profit from the addition of plasminogen. Western and dot blot analyses showed that R<jats:sub>high</jats:sub> as well as R<jats:sub>low</jats:sub> are able to adsorb horse fibronectin and plasminogen present in the growth medium. Depletion of HeLa cell membranes from cholesterol resulted in increased adhesion, but decreased cell invasion.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Conclusion</jats:title>
<jats:p>ECM molecules seem to play a supportive role in the adhesion/cell invasion process of <jats:italic>M. gallisepticum.</jats:italic> Cholesterol depletion known to affect lipid rafts on the host cell surface had contrary effects on cell adherence and cell invasion of <jats:italic>M. gallisepticum.</jats:italic>
</jats:p>
</jats:sec>