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Proteolytic activity of Cryptococcus neoformans against human plasma proteins

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Summary

Although Cryptococcus neoformans is not regarded as proteolytic, the sensitive technique of immunoelectrophoresis has demonstrated its ability to degrade human α2HS-glycoprotein and split up human as also pure cattle fibrinogen under in vitro conditions. If it is assumed that this organism exerts similar effects under in vivo conditions, then the present observations permit the explanation for the characteristic lack of fibrosis and hyalinization around tissue lesions in the disseminating form of the disease.

Zusammenfassung

Bisher war eine proteolytische Enzymaktivität bei Cryptococcus neoformans unbekannt. Mit Hilfe der Immunelektrophorese gelang uns der Nachweis, daß Cryptococcus neoformans in vitro sowohl das α2HS-Glykoprotein wie das Fibrinogen enzymatisch angreifen kann.

Damit wird erklärlich, weshalb Cryptococcus neoformans so reaktionslos im Wirtsorganismus wachsen kann : Die Schleimkapsel des Pilzes blockiert die humorale und celluläre Immunreaktion und durch die Fähigkeit zum Abbau von Fibrinogen wird jede Fibrinablagerung und damit auch die nachfolgende Fibrosierung verhindert.

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Authors and Affiliations

  1. Institut für Medizinische Mikrobiologie und Immunologie der Universität Bonn, Germany

    H. E. Müller & K. K. Sethi

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  1. H. E. Müller
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  2. K. K. Sethi
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Additional information

This investigation was supported by the Deutsche Forschungsgemeinschaft. We thank Mrs. E. Lips for skilful technical assistance.

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Müller, H.E., Sethi, K.K. Proteolytic activity of Cryptococcus neoformans against human plasma proteins. Med Microbiol Immunol 158, 129–134 (1972). https://doi.org/10.1007/BF02120478

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  • DOI: https://doi.org/10.1007/BF02120478

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