Innate Immune Response of Human Embryonic Stem Cell‐Derived Fibroblasts and Mesenchymal Stem Cells to Periodontopathogens

Abstract

Periodontitis involves complex interplay of bacteria and host immune response resulting in destruction of supporting tissues of the tooth. Toll-like receptors (TLRs) play a role in recognizing microbial pathogens and eliciting an innate immune response. Recently, the potential application of multipotent stem cells and pluripotent stem cells including human embryonic stem cells (hESCs) in periodontal regenerative therapy has been proposed. However, little is known about the impact of periodontopathogens on hESC-derived progenies. This study investigates the effects of heat-killed periodontopathogens, namely, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, on TLR and cytokine expression profile of hESC-derived progenies, namely, fibroblasts (hESC-Fib) and mesenchymal stem cells (hESC-MSCs). Additionally, the serotype-dependent effect of A. actinomycetemcomitans on hESC-derived progenies was explored. Both hESC-Fib and hESC-MSCs constitutively expressed TLR-2 and TLR-4. hESC-Fib upon exposure to periodontopathogens displayed upregulation of TLRs and release of cytokines (IL-1β, IL-6, and IL-8). In contrast, hESC-MSCs were largely nonresponsive to bacterial challenge, especially in terms of cytokine production. Further, exposure of hESC-Fib to A. actinomycetemcomitans serotype c was associated with higher IL-8 production than serotype b. In contrast, the hESC-MSCs displayed no serotype-dependent response. Differential response of the two hESC progenies implies a phenotype-dependent response to periodontopathogens and supports the concept of immunomodulatory properties of MSCs.

In Vitro Osteogenic Potential of Green Fluorescent Protein Labelled Human Embryonic Stem Cell‐Derived Osteoprogenitors

“…The expression of surface markers (CD73, CD90, and CD105), data from gene expression analysis, and Alizarin Red and immunofluorescent staining demonstrate the osteogenic commitment and differentiation potential of these GFP-expressing hESCs. These results are in agreement with previous studies [10, 15, 20, 34, 35]. These data also suggest the stable expression of GFP in hESC-OPs and the genetic manipulation did not affect their osteogenic differentiation.…”

“…Jeon et al used a biomimetic approach to regenerate bone by 3D coculture of human PSC-derived osteoblasts and osteoclasts within a synthetic scaffolds [46]. We have recently developed protocols to direct the differentiation of hESCs to vascular cells [20, 47]. In future studies, we plan to address the osteodifferentiation potential of hESC-OPs cocultured with vascular cells within 3D scaffolds to generate vascularized bone tissues.…”

“…These cells were cultured on feeder-dependent system using mitomycin-C inactivated murine embryonic fibroblasts (MEFs) and hESC medium as described previously [20]. Briefly, the hESC medium consisted of Dulbecco's modified Eagle's medium (DMEM)/Ham's F12 (1 : 1) supplemented with 20% Knockout Serum Replacement (KO-SR; GIBCO), 1% (vol/vol) nonessential amino acids (Sigma-Aldrich), 1 mM L-glutamine (GIBCO), 4 ng/mL basic fibroblast growth factor (bFGF; Invitrogen), and 0.1 mM β -mercaptoethanol (Sigma-Aldrich).…”

Directed Differentiation of Human Embryonic Stem Cells to Neural Crest Stem Cells, Functional Peripheral Neurons, and Corneal Keratocytes

“…Cells were dissociated into single cells with TrypLE™/Accutase, and stained directly with conjugated antibodies (Table S2, Supporting Information) according to the manufacturer's instruction . Stained cells were analyzed with BD LSRFortessa (Becton Dickinson) and FlowJo software.…”

Immunomodulatory Properties of Stem Cells in Periodontitis: Current Status and Future Prospective

“…The immunoregulatory effects of stem cells make them a promising therapy for periodontitis. Although several reports have indicated that the stem cells mentioned above can be delivered into infectious sites and function as critical players in the control of inflammation and the regulation of immune responses to achieve regeneration in models of periodontitis, the immunomodulatory capabilities of these cells have not entirely been elucidated [ 137 , 138 ]. Moreover, evidence of stem cell-mediated immunomodulation is limited both in vitro and in vivo .…”