Interleukin-17/T-helper 17 cells in an atopic dermatitis mouse model aggravate orthodontic root resorption in dental pulp.

Interleukin (IL)-17 is an important mediator of orthodontically induced inflammatory root resorption (OIIRR). However, its role in the dental pulp (DP) has not been studied. The aim of this study was to investigate, using an atopic dermatitis (AD) model, how IL-17 contributes to OIIRR in DP. Atopic dermatitis is the most common IL-17-associated allergic disease. Atopic dermatitis model mice (AD group) and wild-type mice (control group) were subjected to an excessive orthodontic force. The localization of T-helper (Th)17 cells, IL-17, IL-6, and keratinocyte chemoattractant (KC; an IL-8-related protein in rodents) were determined in DP. In addition, CD4+ T cells, including IL-17 production cells, were obtained from patients with AD and from healthy donors, and the effects of IL-17 on the production of IL-6 and IL-8 were investigated using a co-culture of CD4+ T cells with human dental pulp (hDP) cells stimulated with substance P (SP). Immunoreactivity for Th17 cells, IL-17, IL-6, and KC was increased in DP tissue subjected to orthodontic force in the AD group compared with DP tissue subjected to orthodontic force in the control group. The cells obtained from the AD patients displayed increased IL-6 and IL-8 production. These results suggest that IL-17 may aggravate OIIRR in DP.

Kaempferol stimulates bone sialoprotein gene transcription and new bone formation.

Kaempferol is a typical flavonol-type flavonoid that is present in a variety of vegetables and fruits, and has a protective effect on postmenopausal bone loss. Bone sialoprotein (BSP) is thought to function in the initial mineralization of bone and could be crucial for osteoblast differentiation, bone matrix mineralization and tumor metastasis. In the present study we investigated the regulation of BSP transcription by kaempferol in rat osteoblast-like UMR106 cells, and the effect of kaempferol on new bone formation. Kaempferol (5 microM) increased BSP and Osterix mRNA levels at 12 h and up-regulated Runx2 mRNA expression at 6 h. Kaempferol increased luciferase activity of the construct pLUC3, which including the promoter sequence between nucleotides -116 to +60. Transcriptional stimulation by kaempferol abrogated in constructs included 2 bp mutations in the inverted CCAAT, CRE, and FRE elements. Gel shift analyses showed that kaempferol increased nuclear protein binding to CRE and FRE elements, whereas the CCAAT-protein complex did not change after kaempferol stimulation. Twelve daily injections of 5 microM kaempferol directly into the periosteum of parietal bones of newborn rats increased new bone formation. These data suggest that kaempferol increased BSP gene transcription mediated through inverted CCAAT, CRE, and FRE elements in the rat BSP gene promoter, and could induce osteoblast activities in the early stage of bone formation.

The tyrosine phosphatase CD148 interacts with the p85 regulatory subunit of phosphoinositide 3-kinase.

CD148 is a transmembrane tyrosine phosphatase that has been implicated in the regulation of cell growth and transformation. However, the signalling mechanisms of CD148 are incompletely understood. To identify the specific intracellular molecules involved in CD148 signalling, we carried out a modified yeast two-hybrid screening assay. Using the substrate-trapping mutant form of CD148 (CD148 D/A) as bait, we recovered the p85 regulatory subunit of PI3K (phosphoinositide 3-kinase). CD148 D/A, but not catalytically active CD148, interacted with p85 in a phosphorylation-dependent manner in vitro and in intact cells. Growth factor receptor and PI3K activity were also trapped by CD148 D/A via p85 from pervanadate-treated cell lysates. CD148 prominently and specifically dephosphorylated p85 in vitro. Co-expression of CD148 reduced p85 phosphorylation induced by active Src, and attenuated the increases in PI3K activity, yet CD148 did not alter the basal PI3K activity. Finally, CD148 knock-down by siRNA (short interfering RNA) increased PI3K activity on serum stimulation. Taken together, these results demonstrate that CD148 may interact with and dephosphorylate p85 when it is phosphorylated and modulate the magnitude of PI3K activity.

Expression profile of chemokines and chemokine receptors in epithelial cell layers of oral lichen planus.

BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. METHODS: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5.

Case report of intra-osseous fibroma: a study on odontogenic and desmoplastic fibromas with a review of the literature.

Intra-osseous fibromas of the jaw are classified by origin. Intra-osseous odontogenic fibromas have odontogenic epithelia, while desmoplastic fibromas do not. However, it is often difficult to determine the odontogenic origin for central fibromas. Three subjects with a diagnosis of intra-osseous fibroma were examined. Case 1 was a 35-year-old man found to have a panoramic radiograph from the right premolar to the mandibular ramus in the mandible that exhibited multilocular radiolucency. Within the radiolucency, small-radioopaque bodies were observed. Case 2 was a 13-year-old female, in whom a panoramic radiograph from the left premolar to the molar in the mandible showed multilocular radiolucency. Case 3 was a 51-year-old female who exhibited a heart-shaped radiolucency in the panoramic radiograph of the left first molar area in the mandible. We also reviewed the literature for previously reported cases of intra-osseous odontogenic and desmoplastic fibroma. In 64 cases of intra-osseous odontogenic fibroma and 68 cases of desmoplastic fibroma we extracted data on age, sex, location, and radiographic findings. Based on the analysis of the reported literature cases, re-evaluation of the patients in our study revealed that case 1 could be classified as desmoplastic fibroma, while cases 2 and 3 were intra-osseous odontogenic fibromas.

Cellular schwannoma in the oral mucosa.

A case of cellular schwannoma of the oral mucosa in a 34-year-old Japanese man is described. Cellular schwannoma commonly affects soft tissues such as the retroperitoneum and posterior mediastinum, and also bone, but is extremely rare in the oral region. To our knowledge, this is only the second report of oral cellular schwannoma. Histologically, the tumor parenchyma consisted of hypercellular spindle cells with nuclear and cytoplasmic pleomorphism and nuclear palisading resembling Antoni A-type conventional schwannoma, without evidence of Verocay bodies. These features were indicative of cellular schwannoma. Immunohistochemically, the tumor cells were positive for S-100, S-100alpha, S-100beta and vimentin, suggesting that they were of peripheral nervous origin. Furthermore, it is speculated that the tumor was intermediate between a benign and a malignant state, based on the histological features and positivity for S-100alpha.