Flowzytometrische Erfassung der Phagozytose schwarzer Hefen durch humane Granulozyten

Black yeasts, having been increasingly isolated from patients, may cause a wide range of opportunistic mycotic diseases. Simply cutaneous infections are found as well as severe systemic infections which frequently lead to death. Using flow cytometry we analysed the phagocytic activity of yeast cells by human polymorphonuclear granulocytes (PNG) after co-incubation with heparinized complete blood of healthy donors. To obtain yeast-like growth, all strains were cultured in standardized media. Using fluorescently (BCECF-AM) labelled yeasts we had been able to distinguish yeast-cells that had been phagocytised (or adhered to) by PNG from free (non-phagocytised) yeast cells. The further quantitative analysis focused on human neutrophils participating in phagocytosis. After a co-incubation time of 60 min, phagocytosis rates were comparable for all species analysed, on an average of 80%. Yeast strains with a frequent pathogenic potential (Exophiala dermatitidis, Exophiala jeanselmei), less pathogenic strains (Exophiala castellanii, Exophiala bergeri, Hortaea werneckii, Phaeoannellomyces elegans), one non-pathogenic strain (Exophiala mesophila) and two non-pigmented strains (Candida albicans, Saccharomyces cerevisiae) had been tested. Trying to inhibit phagocytic activity we used murine monoclonal antibodies (mab) against (2-integrins (CD11a, CD11b, CD11c alone and in combination with CD18). For all yeast strains tested a significant inhibitation of the phagocytic activity of human neutrophils could only be seen after co-incubation with mab CD11b and CD18 (inhibitation on an average of 50%). Consequently the granulocytic complement-receptor Mac-1 (CD11b/CD18, CR3) had been identified as an essential receptor for adhesion and final phagocytosis of black yeasts und other medically important fungi.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2004

Author dc:creator

• Platz, Andreas

Contributors dc:contributor

• Haase, Gerhard

• info:eu-repo/classification/ddc/610
• Medizin
• Durchflusszytometrie
• ß2-Integrine
• Mykosen
• Phagozytose
• schwarze Hefen
• humane Granulozyten

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121405%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:59637