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Possible role of odontoblasts in the initiation of the dental pulp immune response to cariogenic bacteria. Oral bacteria that degrade dentine during carious lesions release pathogen-associated molecular patterns (PAMPs; brown dots) that may diffuse through the tubules to the odontoblast layer (brown arrows). Here, they are recognized by specific pathogen recognition receptors (pink cups) present at the odontoblast surface. Activation of specific intracellular pathways (dotted red lines) leads to the production of pro-inflammatory mediators including chemokines (blue squares) secreted at the opposite pole of the cell. These chemokines diffuse in the subodontoblast pulp area (blue arrow) and, upon binding to specific receptors (green boxes) attract antigen-presenting immature dendritic cells that ensure tissue immunosurveillance. These cells migrate to the odontoblast layer (gray arrows) to capture PAMPs arriving at the tubule pulpal end and develop the immune response and the associated inflammation.

Possible role of odontoblasts in the initiation of the dental pulp immune response to cariogenic bacteria. Oral bacteria that degrade dentine during carious lesions release pathogen-associated molecular patterns (PAMPs; brown dots) that may diffuse through the tubules to the odontoblast layer (brown arrows). Here, they are recognized by specific pathogen recognition receptors (pink cups) present at the odontoblast surface. Activation of specific intracellular pathways (dotted red lines) leads to the production of pro-inflammatory mediators including chemokines (blue squares) secreted at the opposite pole of the cell. These chemokines diffuse in the subodontoblast pulp area (blue arrow) and, upon binding to specific receptors (green boxes) attract antigen-presenting immature dendritic cells that ensure tissue immunosurveillance. These cells migrate to the odontoblast layer (gray arrows) to capture PAMPs arriving at the tubule pulpal end and develop the immune response and the associated inflammation.

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... Anti-inflammatory and regenerative roles of the resident cells have been investigated in the resolution of the inflammation in pulps (29,30). In the current study, we were able to identify the upregulation of SERPINA3, a protein known to inhibit neutrophil function (31) and APOE, known to suppress macrophage's proinflammatory responses to lipopolysaccharide (LPS) (Figures 3B,C) (32). ...
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... Odontoblasts play a crucial role in maintaining a balanced pulp microenvironment to regulate transcellular transport between the pulp and dentine [2]. During the progression of caries, odontoblasts can recognize and respond to bacteria, and these cells are the first line of defense against cariogenic bacteria for their specific localization at the pulp-dentin interface [3]. Thus, it is of importance to elucidate the mechanisms by which odontoblasts eliminate invading bacteria. ...
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... Shielded by enamel and dentine, they are the first line of cells to get in contact with toxins and compounds of oral bacteria once the mineralized matrices have started to break down, with caries being the most prevalent cause, followed by dental trauma. Thus, odontoblasts play a central role as mediators of both inflammation and repair processes [4][5][6]. Beneath the odontoblast layer and an adjacent cell-free zone, pulp fibroblasts populate an extracellular matrix mainly made of collagen type I and III [7]. The pulpal core is crossed by vascular and neuronal networks, which enter the tooth through the alveolar bone via the apical foramen. ...
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... Further, odontoblasts are able to recognize the pathogenassociated molecular patterns released by bacteria from carious lesions and produce pro-inflammatory mediators in response (Farges et al., 2013). Odontoblast is important in inflammation defense. ...
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