Publications by authors named "Claire Ehlinger"

6 Publications

  • Page 1 of 1

Insensitivity of dental pulp stem cells migration to substrate stiffness.

Biomaterials 2021 Jun 15;275:120969. Epub 2021 Jun 15.

Inserm UMR-S1121, Centre de Recherche en Biomédecine de Strasbourg (CRBS), 1 rue Eugène Boeckel, 67084, Strasbourg, France; Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000, Strasbourg, France; Fédération de Médecine Translationnelle, Strasbourg, France. Electronic address:

Dental pulp stem cells (DPSCs) are a promising cell source for regeneration of dental pulp. Migration is a key event but influence of the microenvironment rigidity (5 kPa at the center of dental pulp to 20 GPa for the dentin) is largely unknown. Mechanical signals are transmitted from the extracellular matrix to the cytoskeleton, to the nuclei, and to the chromatin, potentially regulating gene expression. To identify the microenvironmental influence on migration, we analyzed motility on PDMS substrates with stiffness increasing from 1.5 kPa up to 2.5 MPa. We found that migration speed slightly increases as substrate stiffness decreases in correlation with decreasing focal adhesion size. Motility is relatively insensitive to substrate stiffness, even on a bi-rigidity PDMS substrate where DPSCs migrate without preferential direction. Migration is independent of both myosin II activity and YAP translocation after myosin II inhibition. Additionally, inhibition of Arp2/3 complex leads to significant speed decrease for all rigidities, suggesting contribution of the lamellipodia in the migration. Interestingly, the chromatin architecture remains stable after a 7-days exposure on the PDMS substrates for all rigidity. To design scaffold mimicking dental pulp environment, similar DPSCs migration for all rigidity, leaves field open to choose this mechanical parameter.
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http://dx.doi.org/10.1016/j.biomaterials.2021.120969DOI Listing
June 2021

A modified inside/outside bleaching technique for nonvital discolored teeth: a case report.

Quintessence Int 2019 ;50(10):802-807

Over the past decades, the walking bleach technique using sodium perborate was considered a safe and effective method to bleach nonvital discolored teeth. However, sodium perborate has been classified as carcinogenic, mutagenic, and toxic for reproduction by European Union legislation. Its use is therefore prohibited since April 2015. The initially described inside/outside bleaching technique, combining internal and external application of 10% carbamide peroxide, is an alternative to the walking bleach technique using sodium perborate. While good esthetic results and low risks of external cervical resorptions have been associated with this technique, its main drawback is that the access cavity is left open. To overcome this disadvantage, the present authors propose to seal the bleaching agent in the access cavity instead of leaving the latter open. Through a clinical case, this paper presents and discusses several aspects of this protocol, including the clinical steps, the design of the bleaching tray, and the treatment of potential recurrences. The present authors believe that the protocol proposed in this article is easier to use for the patient. Moreover, it prevents the accumulation of food debris in the access cavity and avoids the colonization of coronary dentin by bacteria.
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http://dx.doi.org/10.3290/j.qi.a43248DOI Listing
November 2019

Decision criteria influencing the therapeutic approach to invasive cervical resorption: a case series.

Quintessence Int 2019 ;50(6):494-502

Invasive cervical resorption (ICR) is a dental lesion starting in the cervical region and involving the loss of dental hard tissue as a result of odontoclastic action. Due to its localization and invasive pattern, this process represents a challenging clinical situation. When feasible, the major aim of an ICR treatment is to completely remove the pathologic tissue (specifically at the entry point of the lesion) and to seal the resulting defect, without compromising tooth rehabilitation. In this context, choosing how to access the resorptive lacuna is essential. Two main options have been described in the literature: an external approach, requiring the surgical exposure of the resorptive lacuna, and an internal approach, taking advantage of the endodontic access cavity. However, there are no guidelines that indicate which approach to choose for the treatment of an ICR. This article is based on four clinical cases. It aims to provide specific clinical and radiologic features that should be considered in order to take the most appropriate decision, when choosing between the internal and the external approaches. It is proposed to base the therapeutic strategy on the accessibility and the size of the portal of entry of the lesion. When the entry point is wide, its extension along the root must also be taken into account. Other important parameters are the circumferential and vertical extents of the lesion in the radicular dentin. Although it is not a determining factor, the pulpal involvement of the lesion can also be considered.
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http://dx.doi.org/10.3290/j.qi.a42479DOI Listing
November 2019

Chromatin de-condensation by switching substrate elasticity.

Sci Rep 2018 08 23;8(1):12655. Epub 2018 Aug 23.

Inserm UMR-S1121, 11 rue Humann, 67085, Strasbourg, France.

Mechanical properties of the cellular environment are known to influence cell fate. Chromatin de-condensation appears as an early event in cell reprogramming. Whereas the ratio of euchromatin versus heterochromatin can be increased chemically, we report herein for the first time that the ratio can also be increased by purely changing the mechanical properties of the microenvironment by successive 24 h-contact of the cells on a soft substrate alternated with relocation and growth for 7 days on a hard substrate. An initial contact with soft substrate caused massive SW480 cancer cell death by necrosis, whereas approximately 7% of the cells did survived exhibiting a high level of condensed chromatin (21% heterochromatin). However, four consecutive hard/soft cycles elicited a strong chromatin de-condensation (6% heterochromatin) correlating with an increase of cellular survival (approximately 90%). Furthermore, cell survival appeared to be reversible, indicative of an adaptive process rather than an irreversible gene mutation(s). This adaptation process is associated with modifications in gene expression patterns. A completely new approach for chromatin de-condensation, based only on mechanical properties of the microenvironment, without any drug mediation is presented.
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http://dx.doi.org/10.1038/s41598-018-31023-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6107547PMC
August 2018

D-Cateslytin: a new antifungal agent for the treatment of oral Candida albicans associated infections.

Sci Rep 2018 06 18;8(1):9235. Epub 2018 Jun 18.

INSERM UMR 1121, Biomatériaux et Bioingénierie, Université de Strasbourg, 11 rue Humann, 67085, Strasbourg, France.

The excessive use of antifungal agents, compounded by the shortage of new drugs being introduced into the market, is causing the accumulation of multi-resistance phenotypes in many fungal strains. Consequently, new alternative molecules to conventional antifungal agents are urgently needed to prevent the emergence of fungal resistance. In this context, Cateslytin (Ctl), a natural peptide derived from the processing of Chromogranin A, has already been described as an effective antimicrobial agent against several pathogens including Candida albicans. In the present study, we compared the antimicrobial activity of two conformations of Ctl, L-Ctl and D-Ctl against Candida albicans. Our results show that both D-Ctl and L-Ctl were potent and safe antifungal agents. However, in contrast to L-Ctl, D-Ctl was not degraded by proteases secreted by Candida albicans and was also stable in saliva. Using video microscopy, we also demonstrated that D-Ctl can rapidly enter C. albicans, but is unable to spread within a yeast colony unless from a mother cell to a daughter cell during cellular division. Besides, we revealed that the antifungal activity of D-Ctl could be synergized by voriconazole, an antifungal of reference in the treatment of Candida albicans related infections. In conclusion, D-Ctl can be considered as an effective, safe and stable antifungal and could be used alone or in a combination therapy with voriconazole to treat Candida albicans related diseases including oral candidosis.
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http://dx.doi.org/10.1038/s41598-018-27417-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6006364PMC
June 2018

D-Cateslytin, a new antimicrobial peptide with therapeutic potential.

Sci Rep 2017 11 9;7(1):15199. Epub 2017 Nov 9.

Université de Strasbourg, Faculté de Chirurgie Dentaire, 3 rue Sainte Elisabeth, 67000, Strasbourg, France.

The rise of antimicrobial resistant microorganisms constitutes an increasingly serious threat to global public health. As a consequence, the efficacy of conventional antimicrobials is rapidly declining, threatening the ability of healthcare professionals to cure common infections. Over the last two decades host defense peptides have been identified as an attractive source of new antimicrobials. In the present study, we characterized the antibacterial and mechanistic properties of D-Cateslytin (D-Ctl), a new epipeptide derived from L-Cateslytin, where all L-amino acids were replaced by D-amino acids. We demonstrated that D-Ctl emerges as a potent, safe and robust peptide antimicrobial with undetectable susceptibility to resistance. Using Escherichia coli as a model, we reveal that D-Ctl targets the bacterial cell wall leading to the permeabilization of the membrane and the death of the bacteria. Overall, D-Ctl offers many assets that make it an attractive candidate for the biopharmaceutical development of new antimicrobials either as a single therapy or as a combination therapy as D-Ctl also has the remarkable property to potentiate several antimicrobials of reference such as cefotaxime, amoxicillin and methicillin.
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http://dx.doi.org/10.1038/s41598-017-15436-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5680178PMC
November 2017