Polymerization of misfolded Z alpha-1antitrypin protein lowers CX3CR1 expression in human PBMCs
- Hannover Medical School, Germany
- 8sens.biognostic GmbH, Germany
- Instituto de Salud Carlos III, Spain
- University Hospital RWTH Aachen, Medical Clinic III, Germany
- University 18 Hospital RWTH Aachen, Germany
- Leiden University Medical Center, Netherlands
Abstract
The CX3CR1 (chemokine (C-X3-C motif) receptor 1) expression levels on immune cells have significant importance in maintaining tissue homeostasis under physiological and pathological conditions. The factors implicated in the regulation of CX3CR1 and its specific ligand CX3CL1 (fractalkine) expression remain largely unknown. Recent studies provide evidence that host`s misfolded proteins occurring in the forms of polymers or amyloid fibrils can regulate CX3CR1 expression. Herein, a novel example demonstrates that polymers of human ZZ alpha-1 antitrypsin (Z-AAT) protein, resulting from its conformational misfolding due to the Z (Glu342Lys) mutation in SERPINA1 gene, strongly lower CX3CR1 mRNA expression in human PBMCs. This parallels with increase of intracellular levels of CX3CR1 and Z-AAT proteins. Presented data indicate the involvement of the CX3CR1 pathway in the Z-AAT-related disorders and further support the role of misfolded proteins in CX3CR1 regulation.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures
Article and author information
Author details
Matthias Ballmaier
Beatriz Martinez-Delgado
Sabina Janciauskiene
Funding
Deutsche Forschungsgemeinschaft (STR 1095/6-1)
- Pavel Strnad
Deutsche Zentrum für Lungenforschung (82DZL002A)
- Sabina Janciauskiene
Deutsche Forschungsgemeinschaft (SFB/TRR57)
- Pavel Strnad
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The institutional review board of Aachen University (EK 173/15) provided ethical approval for individuals recruited in Germany. Leiden University Medical Center provided ethical approval (project P00.083 and P01.101) for the second study group. For all individuals detailed medical records data were anonymized. All participants issued a written informed consent according to the ethical guidelines of the Helsinki Declaration (Hong Kong Amendment) as well as Good Clinical Practice (European guidelines).
Copyright
© 2021, Tumpara et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Polymerization of misfolded Z alpha-1antitrypin protein lowers CX3CR1 expression in human PBMCs
eLife 10:e64881.
https://doi.org/10.7554/eLife.64881
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