Dental pulp stem cells induce anti-inflammatory phenotypic transformation of macrophages to enhance osteogenic potential via IL-6/GP130/STAT3 signaling

Abstract

Background Periodontitis is a major oral condition and current treatment outcomes can be unsatisfactory. Macrophages are essential to the regeneration process, so we investigated the influence of human dental pulp stem cells (hDPSCs) on macrophage differentiation and the microenvironment and the underlying mechanism. Methods hDPSCs were isolated from healthy third molars extracted from patients undergoing maxillofacial surgery. The surface antigens CD73, CD45, CD90 and CD11b of the hDPSCs were detected using flow cytometry. hDPSCs were induced for osteogenic and adipogenic differentiation, and the outcome was assessed by alizarin red staining or Oil Red O staining. The IL-6 level released by hDPSCs was measured by enzyme linked immunosorbent assay (ELISA). Tohoku Hospital Pediatrics-1 (THP-1) cells were cultured and induced into macrophages by phorbol-12-myristate-13-acetate. After coculture of THP-1-derived macrophages with hDPSCs, interleukin 6 (IL-6), Argininase-1 (Arg-1), Mannose receptor C-1 (Mrc-1), inducible nitric oxide synthase (iNOS), and tumor necrosis factor-α (TNF-α) levels in the medium were measured using ELISA and quantificational RT-PCR (qRT-PCR). The numbers of CD80 + and CD163 + macrophages were counted by immunofluorescence, and GP130/STAT3 signaling protein expression was detected. After coculturing the culture medium of hDPSCs with human bone marrow stem cells (BMSCs), scratch assays and transwell assays were performed to evaluate cell migration and invasion. Results Alkaline phosphatase (ALP) staining, alizarin red staining, and western blots were performed to assess osteoblast differentiation. The hDPSCs were positive for surface antigens CD73 and CD90 and negative for CD45 and CD11b expression. The level of IL-6 secreted by hDPSCs significantly increased the number of CD80 + cells as well as the levels of Arg-1 and Mrc-1. It also promoted M2 macrophage polarization and activated GP130/STAT3 signaling. However, the medium cocultured with THP-1-derived macrophages by hDPSCs facilitated the migration, invasion, and osteogenic abilities of human bone marrow-derived stem cells (hBMSCs). Conclusions hDPSCs can regulate the periodontal microenvironment through IL-6 by inducing phenotypic transformation of M2 macrophages and stimulating osteogenic differentiation of BMSCs.

Osteopontin interacts with dendritic cells and macrophages in pulp inflammation: Comprehensive transcriptomic analysis and laboratory investigations

“…Murine MSCs preconditioned with IFN‐γ and IL‐1β produce higher IL‐6, intensify macrophages to express IL10, and shift to M2b (Philipp et al., 2018). Healthy DPSCs also secret IL‐6 to induce M2 polarization (Liu et al., 2023), and current results showed that 20 μg/mL LPS has a strong effect on prompting DPCs IL‐6 expression. Thus, it is indicated that LPS‐induced DPCs may activate macrophage to M2b through IL‐6 paracrine pathway.…”

Development of Glycosylation-Modified DPPA-1 Compounds as Innovative PD-1/PD-L1 Blockers: Design, Synthesis, and Biological Evaluation

“…The cells were then fixed with 4% paraformaldehyde and incubated with anti-human-IL-2-APC (MQ1-17H12; eBioscience, San Diego, CA, USA) for 30 min. Flow cytometry was used for detection and analysis [37].…”

Inhibition of ZDHHC16 promoted osteogenic differentiation and reduced ferroptosis of dental pulp stem cells by CREB

“…Stem cells isolated from various tissues have different biological characteristics and different osteogenic differentiation (OD) abilities [ 7 ]. Among them, the stem cells derived from bone marrow are the most studied, and the dental pulp stem cells (DPSCs) are also widely studied because of their excellent OD potential and accessibility [ 8 , 9 ]. Several previous studies have shown that under the control of growth factors, transcription factors, and receptor molecules, DPSCs can differentiate into osteoblasts, adipocytes, odontoblasts, and nerve cells [ 10 , 11 ].…”