Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

The danger signal extracellular calcium is pathophysiologically increased in the synovial fluid of patients with rheumatoid arthritis (RA). Calcium activates the NLRP3-inflammasome via the calcium-sensing receptor in monocytes/macrophages primed by lipopolysaccharide, and this effect is mediated by the uptake of calciprotein particles (CPPs) formed out of calcium, phosphate, and fetuin-A. Aim of the study was to unravel the influence of calcium on monocytes when the priming signal is not present. Monocytes were isolated from the blood of healthy controls and RA patients. Macrophages were characterized using scRNA-seq, DNA microarray, and proteomics. Imaging flow cytometry was utilized to study intracellular events. Here we show that extracellular calcium and CPPs lead to the differentiation of monocytes into calcium-macrophages when the priming signal is absent. Additional growth factors are not needed, and differentiation is triggered by calcium-dependent CPP-uptake, lysosomal alkalization due to CPP overload, and TFEB- and STAT3-dependent increased transcription of the lysosomal gene network. Calcium-macrophages have a needle-like shape, are characterized by excessive, constitutive SPP1/osteopontin production and a strong pro-inflammatory cytokine response. Calcium-macrophages differentiated out of RA monocytes show a stronger manifestation of this phenotype, suggesting the differentiation process might lead to the pro-inflammatory macrophage response seen in the RA synovial membrane.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8755842PMC
http://dx.doi.org/10.1038/s41419-022-04507-3DOI Listing

Publication Analysis

Top Keywords

extracellular calcium
12
danger signal
8
signal extracellular
8
differentiation monocytes
8
priming signal
8
calcium
6
monocytes
5
calcium initiates
4
differentiation
4
initiates differentiation
4

Similar Publications

New insights to B cell tolerance involving the mechanosensitive ion channel Piezo1.

BMB Rep

September 2025

Department of Microbiology and Immunology, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea; Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea; Institute for Immunology and Immunological Diseases, Yonsei Uni

B cell tolerance is critical for preventing autoimmunity, yet the mechanisms by which B cells discriminate self from non-self antigens remain incompletely understood. While early findings emphasize the role of classical antigen-mediated BCR signaling strength by varying antigen formats, emerging evidence highlights the importance of mechanical cues during antigen recognition. This review explores how mechanosensitive ion channels, particularly Piezo1, contribute to B cell activation and tolerance by integrating physical forces at the immune synapse.

View Article and Find Full Text PDF

Effects of dermal-fibroblast-derived ECM and dextran sulfate supplementation on osteoblast differentiation - results of a preliminary in vitro study.

Injury

August 2025

Department of Trauma Surgery, University and University Hospital of Zurich, Raemistr. 100, 8091 Zurich, Switzerland; Center for Preclinical Development, University and University Hospital of Zurich, Raemistr. 100, 8091 Zurich, Switzerland. Electronic address:

Background: Critical size bone defects represent a clinical challenge, associated with considerable morbidity, and frequently trigger the requirement of secondary procedure. To fill osseous gaps, multiple steps are required, such as proliferation and differentiation on the cellular level and the building of extracellular matrix. In addition, the osteogenic potential of cell-derived extracellular matrices (CD-ECM) is known to enhance bone healing.

View Article and Find Full Text PDF

Glutamate-mediated excitotoxicity represents a common pathomechanism in neurological disorders. As the predominant glutamate transporter in the central nervous system, glutamate transporter 1 (GLT-1, known as EAAT2 in humans) plays a crucial role in maintaining glutamate homeostasis and preventing excitotoxicity through its Na⁺-dependent transport mechanism. Key functions of GLT-1 include reducing extracellular glutamate concentration, regulating calcium homeostasis, suppressing oxidative stress, preserving mitochondrial integrity, and modulating neuroinflammatory processes by limiting microglial activation.

View Article and Find Full Text PDF

During heart disease, the cardiac extracellular matrix (ECM) undergoes a structural and mechanical transformation. Cardiomyocytes sense the mechanical properties of their environment, leading to phenotypic remodeling. A critical component of the ECM mechanosensing machinery, including the protein talin, is organized at the cardiomyocyte costamere.

View Article and Find Full Text PDF

The sodium leak channel NALCN, a key regulator of neuronal excitability, associates with three ancillary subunits that are critical for its function: a subunit called FAM155, which interacts with the extracellular regions of the channel, and two cytoplasmic subunits called UNC79 and UNC80. Interestingly, NALCN and FAM155 have orthologous phylogenetic relationships with the fungal calcium channel Cch1 and its subunit Mid1; however, UNC79 and UNC80 have not been reported outside of animals. In this study, we leveraged expanded gene sequence data available for eukaryotes to reexamine the evolutionary origins of NALCN and Cch1 channel subunits.

View Article and Find Full Text PDF