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BMC Ophthalmology

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Open Access 01-12-2018 | Research article

Phospholipase Cγ2 is critical for Ca²⁺ flux and cytokine production in anti-fungal innate immunity of human corneal epithelial cells

Authors: Xudong Peng, Guiqiu Zhao, Jing Lin, Jianqiu Qu, Yingxue Zhang, Cui Li

Published in: BMC Ophthalmology | Issue 1/2018

Abstract

Background

Fungal keratitis (FK) is a sight-threatening disease, accounting for a significant portion with its complex presentation, suboptimal efficacy of the existing therapies and uncontrollable excessive innate inflammation. Phospholipase C-γ2 (PLCγ2) is a non-receptor tyrosine kinase that plays an important role at the early period of innate immunity. This study aimed to identify the role of PLCγ2 in Dectin-1-mediated Ca²⁺ Flux and its effect on the expression of proinflammatory mediators at the exposure to Aspergillus fumigatus (A. fumigatus) hyphae antigens in human corneal epithelial cells (HCECs).

Methods

The HCECs were preincubated with or without different inhibitors respectively before A. fumigatus hyphae stimulation. Intracellular calcium flux in HCECs and levels of PLCγ2 and spleen-tyrosine kinase (Syk) were detected by fluorescence imaging and Western Blotting. The expression of proinflammatory mediators was determined by reverse transcriptase polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA).

Results

We demonstrated that an intracellular Ca²⁺ flux in HCECs was triggered by A. fumigatus hyphae and could be reduced by pre-treatment with PLCγ2-inhibitor U73122. A. fumigatus hyphae induced PLCγ2 phosphorylation was regulated by Dectin-1 via Syk. Furthermore, PLCγ2-deficient HCECs showed a drastic impairment in the Ca²⁺ signaling and the secretion of IL-6, CXCL1 and TNF-α.

Conclusions

PLCγ2 plays a critical role for Ca²⁺ Flux in HCECs stimulated by A. fumigatus hyphae. Syk acts upstream of PLCγ2 in the Dectin-1 signaling pathway. The expressions of proinflammatory mediators induced by A. fumigatus are regulated by the activation of Dectin-1-mediated PLCγ2 signaling pathway in HCECs.

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Title: Phospholipase Cγ2 is critical for Ca2+ flux and cytokine production in anti-fungal innate immunity of human corneal epithelial cells
Authors: Xudong Peng
Guiqiu Zhao
Jing Lin
Jianqiu Qu
Yingxue Zhang
Cui Li
Publication date: 01-12-2018
Publisher: BioMed Central
Published in: BMC Ophthalmology / Issue 1/2018
Electronic ISSN: 1471-2415
DOI: https://doi.org/10.1186/s12886-018-0847-6

At a glance: The ONWARDS insulin icodec trials

Springer Medicine

Phospholipase Cγ2 is critical for Ca²⁺ flux and cytokine production in anti-fungal innate immunity of human corneal epithelial cells

Abstract

Background

Methods

Results

Conclusions

At a glance: The ONWARDS insulin icodec trials

Springer Medicine

Abstract

Background

Methods

Results

Conclusions

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