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Journal of Neuroinflammation
Published in: Journal of Neuroinflammation 1/2013

Open Access 01-12-2013 | Research

Toll-like receptor stimulation increases phagocytosis of Cryptococcus neoformans by microglial cells

Authors: Sandra Redlich, Sandra Ribes, Sandra Schütze, Helmut Eiffert, Roland Nau

Published in: Journal of Neuroinflammation | Issue 1/2013

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Abstract

Background

Toll-Like receptors (TLRs) belong to the family of pattern-recognition receptors with a crucial function of recognising pathogen-associated molecular patterns (PAMPs). Cryptococcal meningitis is a potentially fatal disease with a high mortality and risk of neurological sequelae.

Methods

We studied the ability of microglial cells to increase the phagocytosis of cryptococci after stimulation with agonists of TLR1/2, TLR3, TLR4 and TLR9.

Results

Stimulation of murine microglial cells with these TLR agonists for 24 h increased the phagocytosis of encapsulated Cryptococcus neoformans. Stimulation increased the release of TNF-α, CXCL1 (KC), IL-6, IL-10 and MIP-2, which indicated the activation of microglial cells. Unstimulated and TLR agonist-stimulated MyD88-deficient cells showed a reduced ability to phagocytose cryptococci compared to their wild-type counterpart. Intracellular killing of cryptococci was also increased in TLR-stimulated cells compared to unstimulated microglial cells.

Conclusion

Our observation suggests that stimulation of microglial cells by TLR agonists can increase the resistance of the brain against CNS infections caused by Cryptococcus neoformans. This may be of interest when an immunocompromised patient is unable to eliminate Cryptococcus neoformans despite antifungal therapy.
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Metadata
Title
Toll-like receptor stimulation increases phagocytosis of Cryptococcus neoformans by microglial cells
Authors
Sandra Redlich
Sandra Ribes
Sandra Schütze
Helmut Eiffert
Roland Nau
Publication date
01-12-2013
Publisher
BioMed Central
Published in
Journal of Neuroinflammation / Issue 1/2013
Electronic ISSN: 1742-2094
DOI
https://doi.org/10.1186/1742-2094-10-71

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