Applicability of human dental follicle cells to bone regeneration without dexamethasone: an in vivo pilot study.

The aim of this study was to investigate the capacity of human dental follicle cells (hDFCs) for bone formation in vivo. hDFCs were obtained from wisdom teeth extracted from patients aged 14 and 22 years. hDFCs from the 5th to 8th passages were grown in three-dimensional (3D) culture using gelatin sponges. Cells were transplanted onto the calvaria of F344/NJcl-rnu/rnu male rats (immunodeficient rats). Haematoxylin and eosin (HE) staining and immunohistochemistry were performed, and newly formed bone was evaluated by micro-computed tomography (micro-CT). HE staining showed newly formed bone in 3D culture. Immunohistochemistry showed bone morphogenetic protein 2 (BMP-2), runt-related transcription factor 2 (RUNX2), and osterix staining in areas with newly formed bone. Furthermore, micro-CT showed that, in comparison to controls, transplanted hDFCs promoted better bone quality and bone mineral density (BMD 582 ± 131.1 vs. 300.5 ± 77.7 mg/cm(3); P=0.039), bone mineral content (BMC 5.6 ± 1.1 vs. 2.1 ± 0.4 mg; P = 0.006), bone volume (BV 9.7 ± 0.5 × 10(-3) vs. 7.0 ± 0.4 × 10(-3) cm(3); P = 0.002), BMC/total volume (TV) (399.9 ± 76.3 vs. 147.7 ± 30.8 mg/cm(3); P = 0.006), and BV/TV (69.1 ± 3.6% vs. 49.6 ± 3.1%; P=0.002). This suggests that human dental follicles are potentially useful for regenerative therapy.

JTK-853, a novel non-nucleoside hepatitis C virus polymerase inhibitor, demonstrates a high genetic barrier to resistance in vitro.

JTK-853 is a novel, non-nucleoside, palm site-binding hepatitis C virus (HCV) polymerase inhibitor that has demonstrated antiviral activity in HCV-infected patients during 3 days of treatment. To estimate the genetic barrier of JTK-853 to resistance in vitro, colony formation assays were conducted using HCV replicon cells (genotypes 1a and 1b). The colony formation assays revealed that the numbers of resistant colonies for JTK-853 were much lower than those for other direct-acting antivirals, including palm site- or thumb pocket-binding non-nucleoside HCV polymerase inhibitors (NNIs), an NS5A inhibitor (NS5Ai), and a protease inhibitor (PI). Furthermore, the numbers of resistant colonies for JTK-853 in combination with the NS5Ai or PI were lower than those for other combinations of NS5Ai + NNI, and NS5Ai + PI. Our findings demonstrate that JTK-853 has a high genetic barrier to resistance, and suggest that its combination therapies will be potent in suppressing the emergence of drug resistance in HCV-infected patients.

Characteristics and osteogenic differentiation of stem/progenitor cells in the human dental follicle analyzed by gene expression profiling.

The dental follicle is an ectomesenchymal tissue that surrounds developing tooth germ and that contains osteoblastic-lineage-committed stem/progenitor cells. We examined the osteogenic potential of human dental follicle cells (hDFC) by microarray analysis. We first compared the characteristics of hDFC with those of human bone marrow mesenchymal stem cells (hMSC). Like hMSC, hDFC expressed stem cell markers such as STRO-1 and Notch-1 and differentiated not only into the osteoblastic lineage, but also into the adipogenic lineage. We analyzed the gene expression profiles of hDFC and hMSC that were not differentiated toward the osteogenic lineage. The expression of cell markers and growth factor receptors by hDFC and hMSC was similar, whereas the expression pattern of homeobox genes differed between hDFC and hMSC. Next, we investigated gene expression in hDFC during osteogenic differentiation. Gene expression profiles were analyzed in hDFC cultured in osteogenic induction medium (OIM) or in growth medium (GM) for 3 and 10 days. Many genes whose expression was regulated under these conditions were functionally categorized as "transcription" genes. Osteogenic markers were up-regulated in hDFC during osteogenic differentiation, whereas neurogenic markers were down-regulated. The genes whose expression was regulated in hDFC during osteogenic differentiation were further analyzed by ingenuity pathway analysis and real-time polymerase chain reaction. Bone morphogenetic protein and transforming growth factor-ß signaling pathways were activated in hDFC cultured in OIM for 3 days. This study indicates that the dental follicle contains stem cells and/or osteoblastic progenitor cells and is a potential cellular resource for bone regeneration therapy.

MCP-1 production in temporomandibular joint inflammation.

Synovitis, which is characterized by the infiltration of inflammatory cells, often accompanies progression of temporomandibular joint disorder (TMD) symptoms. Because IL-1ß is elevated in synovial fluids obtained from TMDs, we hypothesized that IL-1ß-responsive genes in synoviocytes may help identify the putative genes associated with synovitis. Using microarray analysis, we found that monocyte chemoattractant protein-1 (MCP-1) mRNA levels were elevated in IL-1ß-stimulated synoviocytes. MCP-1 is a member of the chemokine superfamily. The production of MCP-1 was increased in synoviocytes treated with IL-1ß. When IL-1ß was injected into the cavities of rat TMJs, inflammatory cells and MCP-1-positive cells were detected in the synovial tissues. Furthermore, MCP-1 levels were higher in synovial fluids from individuals with pain compared with those without pain. Inhibitors of MAP-kinases and NF-κB reduced IL-1ß-induced MCP-1 production. These results suggest that MCP-1 stimulated by IL-1ß is one of the factors associated with the inflammatory progression of TMDs.

Expression of cyclooxygenase-1 and -2 in IL-1beta-induced synovitis of the temporomandibular joint.

BACKGROUND: In this study, we analyzed the gene expression profile of fibroblast-like synoviocyte (FLS) cultures from the temporomandibular joint (TMJ) to identify candidate genes associated with intracapsular pathologic conditions of TMJ. Cyclooxygenase (COX)-2 was one of the genes in FLS upregulated following stimulation by interleukin (IL)-1beta, a cytokine thought to play a key role in several pathological conditions. This study investigated the expression of COX-1 and COX-2 in cultured human FLS and rat TMJ synovium following stimulation with IL-1beta. METHODS: RNA was isolated from human FLS after IL-1beta treatment. COX-1 and -2 expression was examined using a GeneChip and real-time polymerase chain reaction. Prostaglandin E(2) (PGE(2)) levels in conditioned media from FLS were measured using enzyme-linked immunosorbent assay. Synovial tissues from TMJs of IL-1beta-injected rats were examined for COX-1 and COX-2 expression by immunohistochemical staining. RESULTS: Following treatment of FLS with IL-1beta, expression of the COX-2 gene increased up to 8 h and peaked at 4 h, whereas COX-1 expression did not change. Stimulation with IL-1beta increased the level of PGE(2) in conditioned media of cultured FLS in a time-dependent manner up to 48 h. Immunohistochemistry showed a strong positive staining for COX-2 in the lining and sub-lining synovial tissues of the TMJ of IL-1beta-injected rats. In contrast, staining for COX-1 was the same in synovial tissues with and without IL-1beta injection. CONCLUSION: These data suggest that COX-2 expression stimulated by IL-1beta stimulates the production of PGE(2) in FLS and plays important roles in the progression of inflammation in TMJ.

Temporal diet changes recorded by stable isotopes in Asiatic black bear (Ursus thibetanus) hair.

Carbon and nitrogen stable isotope ratios were measured in hair samples of the Asiatic black bear (Ursus thibetanus) inhabiting the Northern Japanese Alps (NJA) (n = 20) and the periphery of Nagano City (NC) (n = 6), in Nagano Prefecture, Japan. The hair of NJA bears, which did not have access to anthropogenic foods, showed lower values of d13C and d15N than that of NC bears which had access to garbage and corn fields, especially during the summer. These results reflect somewhat differing diets between the NJA and NC bears. We attempted to assess the feeding history during the hair growth cycle using the growth section analysis method. Each hair sample had been cut into 3?mm lengths from root to tip, labeled, and analyzed along the hair growth. We measured the carbon and nitrogen stable isotope ratios of each 3?mm length of hair sample from one NC bear which had been killed while raiding a corn field. The sections showed wide ranges of isotope ratios, from -23.2% to -14.6% for delta13C, and from 0.3% to 4.6% for delta15N. It was shown that the diet of this bear shifted dramatically from principally C3 plants to more C4 plants and to foods of animal origin. An analysis of the whole hair reflects just the average feeding habit during hair growth, but the present method can trace its diet history. This method can contribute to obtain precise ecological information of wildlife.

Interleukin-1beta increases RANTES gene expression and production in synovial fibroblasts from human temporomandibular joint.

BACKGROUND: Synovial fibroblasts of temporomandibular joint (TMJ) are poorly characterized, although they have important roles in progression of temporomandibular disorders (TMD). In this study, we investigated responses of synovial fibroblasts to interleukin (IL)-1beta. METHODS: We examined gene expression profiles of synovial fibroblasts in response to IL-1beta, using Affymetrix GeneChip. Regulated upon activation normal T-cell expressed and secreted (RANTES) gene expression was confirmed by polymerase chain reaction (PCR) and real-time PCR. RANTES protein levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The RANTES was preferentially up-regulated in synovial fibroblasts by IL-1beta. The increase in RANTES gene expression in response to IL-1beta was confirmed by PCR and real-time PCR. Protein level of RANTES in synovial fibroblasts was also increased by IL-1beta. CONCLUSIONS: The RANTES, a cc-type chemokine, has chemotactic effects on lymphocytes and monocytes. Increased gene expression and protein production of RANTES in synovial fibroblasts, in response to IL-1beta, may play an important role in recruitment of inflammatory cells into synovium and progression of synovitis in TMD.

Successful non-T-cell-depleted nonmyeloablative hematopoietic stem cell transplantation (NST) from an HLA-haploidentical 2-loci-mismatched sibling in a heavily transfused patient with severe aplastic anemia based on the fetomaternal microchimerism.

A 37-year-old Japanese man with systemic hemochromatosis due to multiple transfusions was referred to us for the treatment of severe aplastic anemia (SAA), from which he had been suffering for 24 years. The patient had diabetes arising from the hemochromatosis, chronic anal fissures, and a kidney abscess due to neutropenia. He was treated with a nonmyeloablative preconditioning regimen followed by non-T-cell-depleted (non-TCD) allogeneic peripheral blood stem cell transplantation (PBSCT) from his human leukocyte antigen (HLA)-haploidentical 2-loci-mismatched sibling. Prompt engraftment of granulocytes and platelets was observed, and graft-versus-host disease was easy to control. Noninherited maternal antigens in the donor were confirmed prior to PBSCT, and they were also detected in small quantities in the recipient. This report describes the first successful nonmyeloablative hematopoietic stem cell transplant in a heavily transfused SAA patient from an HLA-haploidentical 2-loci-mismatched sibling donor. The result suggests that a long-term fetomaternal microchimerism-positive sibling can be a second-line donor if an alternative HLA-identical donor is not available.

Monitoring of T-cell repertoire was useful for predicting graft-versus-host disease prognosis in a patient with chronic myelogeneous leukemia after allogeneic bone marrow transplantation.

We analyzed 24 T-cell receptor (TCR)beta chain subfamilies (Vbeta) and the chimerism of a patient with chronic myelogeneous leukemia who underwent allogeneic bone marrow transplantation (allo-BMT). The patient developed liver dysfunction at day 19 leading to worsening of his condition. He died on day 91 of hepatic failure. Complete donor chimerism was observed after day 19. The average complexity score of TCR-Vbeta, which was low on day 19 (5.50), because much lower on day 82 (3.77). The average value of normal volunteers is 7.69. Neither immunosuppressive therapy nor antiviral therapy was effective to treat his hepatic dysfunction. A liver specimen at autopsy showed necrotic tissue with invasion of lymphocytes under the endothelial cells of the bile ducts. These findings suggest that the liver dysfunction was due to graft-versus-host disease (GVHD). Careful monitoring of chimerism and TCR-Vbeta complexity may help to predict the prognosis of GVHD after allogeneic BMT.

Activities of plasminogen activator, plasmin and kallikrein in synovial fluid from patients with temporomandibular joint disorders.

To measure the activities of plasminogen activator (PA), plasmin and kallikrein, multiple synovial fluid samples were taken from 32 patients with internal derangement (ID) and osteoarthrosis (OA), and nine asymptomatic volunteers. The enzyme activity in synovial fluid from the temporomandibular joint (TMJ) was quantitated by a fluorogenic substrate assay using an enzyme substrate. In fluid samples from the patient group, PA was detected in 24 (31.5%), plasmin in 20 (26.3%) and kallikrein in 53 (96.4%), while none of these enzymes were found in the synovial fluid samples from the control group. There were positive correlations found among PA, plasmin and kallikrein. These results clearly demonstrated increased levels of PA, plasmin and kallikrein activities in the synovial fluid of patients with ID and OA, and suggest that these enzymes may be involved in the pathogenesis of synovitis, as well as the resorption of cartilage and bone in TMJ.

IL-1beta increases uPA and uPA receptor expression in human gingival fibroblasts.

The binding of urokinase-type plasminogen activator (uPA) to its receptor (uPAR) in various cell types has been proposed as an important feature of many cellular processes requiring extracellular proteolysis, cell adhesion, motility, and invasion. uPAR attaches to the cell surface with a glycosylphophatidylinositol (GPI) anchor, and serves to localize and accelerate the proteolysis cascade. In this study, we examined both uPA and uPAR levels in human gingival fibroblasts treated with an inflammatory cytokine, interleukin-1beta (IL-1beta). PA activity in the cell lysate was increased by treatment with IL-1beta. Further, PA activity released by phosphatidylinositol-specific phospholipase C, which detaches the GPI anchor, was also increased by IL-1beta. The activity was inhibited by amiloride, a specific inhibitor of uPA. In addition, IL-1beta increased the protein and mRNA levels of both uPA and uPAR in gingival fibroblasts. These findings suggest that the enhancement of uPA and uPAR levels by IL-1beta may play an important role in the progression of periodontal diseases through pericellular proteolysis, and subsequent cellular behavior.

Antitumor cytotoxicity mediated by ligand-activated human V alpha24 NKT cells.

Human V alpha24 NKT cells bearing an invariant V alpha24J alphaQ antigen receptor, the counterpart of the murine V alpha14 NKT cells, are activated by the specific ligand, alpha-galactosylceramide (alpha-GalCer) in a CD1d-dependent manner. Here, we demonstrate that the alpha-GalCer-activated V alpha24 NKT cells exert a potent perforin-dependent cytotoxic activity against a wide variety of human tumor cell lines. In addition, we demonstrate that V alpha24 NKT cells and dendritic cells (DCs) from melanoma patients are functionally normal, even in the tumor-bearing status. The potential use of alpha-GalCer-activated V alpha24 NKT cells and/or DCs from patients for cancer immunotherapy is discussed.

Increase of urokinase-type plasminogen activator receptor expression in human gingival fibroblasts by Porphyromonas gingivalis lipopolysaccharide.

BACKGROUND: Urokinase-type plasminogen activator receptor (uPAR) presenting on the cell surface with glycosylphosphatidylinositol (GPI) anchor is a key component in the plasminogen activator (PA)-plasmin system and plays a critical role in extracellular matrix degradation. It is believed that uPAR serves to localize and accelerate this generation system. In this study, we examined the levels of both uPA and uPAR in human gingival fibroblasts treated with Porphyromonas gingivalis lipopolysaccharide (LPS). METHODS: Human gingival fibroblasts from the seventh to tenth doubling passages were plated at 5x10(4) cells per well in 24-well plates. The confluent-stage cells were cultured for 24 hours in alpha-MEM medium containing 2% fetal calf serum, after which they were incubated with P. gingivalis LPS. PA activity was measured using plasminogen and plasmin substrate S2251. RESULTS: PA activity in the cell lysate was increased by LPS and reached maximum at 1 microg/ml LPS after being incubated for 8 hours. PA activity released by phosphatidylinositol-specific phospholipase C, which detaches the GPI anchor, was also increased by LPS. The activity was inhibited by amiloride, which is a specific inhibitor for uPA. LPS increased the protein and mRNA levels of both uPA and uPAR in gingival fibroblasts. CONCLUSIONS: These findings suggest that increase of the uPAR level by LPS may play an important role in the progression of periodontal diseases through pericellular proteolysis.

[A survey on condition of outpatients at prosthodontics II, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University].

The number of dental patients who have medical illnesses is increasing at the hospital of the Faculty of Dentistry, Tokyo Medical and Dental University. Although prosthodontic treatments are considered less invasive in all dental treatments, invasive procedures such as tooth extraction may be required occasionally. Therefore, it is necessary to treat patients in consideration of their condition. Under this situation, a clinical survey was conducted by health questionnaires answered by the patients who visited our clinic between October 1992 and March 1997. The number of patients whose illness was heart disease, hypertension, diabetes, nephritic disease, hepatitis, tuberculosis, hemodyscrasia, asthma, epilepsy, and so on during dental treatment was higher than the national average according to the Ministry of Health and Welfare. Dental psychosomatic diseases such as TMD and dental phobia were increased every year. These data reflect the contemporary disease structure in Japan characterized by the spreading of life-style related diseases and increase of neuropsychological and infectious diseases.

Elevated serum levels of soluble Fas/APO-1 (CD95) in patients with hepatocellular carcinoma.

Fas (APO-1/CD95)-mediated apoptosis plays an important role in liver cell destruction in viral hepatitis. Using sandwich ELISA, we measured serum levels of soluble Fas (sFas) in patients with hepatocellular carcinoma (HCC) who were positive for hepatitis B surface antigen (HBsAg) or anti-hepatitis C virus (HCV) antibody. sFas levels were significantly higher in HCC patients (median 4.07 ng/ml; range 0.14-29.18 ng/ml) than levels in age-matched healthy donors (0.29 ng/ml; 0-4.90 ng/ ml) (P < 0.0001) and HBsAg or anti-HCV antibody-positive patients with liver cirrhosis (LC) (2.16 ng/ ml; 0.24-8.39 ng/ml) (P = 0.0015). An arbitrary cut-off level of 3.03 ng/ml (mean + 3 s.d. of controls) revealed the positive frequency of sFas in each group: 1.7% in healthy subjects, 25.9% in LC, and 59.0% in HCC (sensitivity 59.0% and specificity 74.1%). All HCC sera tested contained transmembrane-deleted sFas and some contained another sFas lacking the Fas C-terminal. The positive frequency of either sFas (59.0%) or alpha-fetoprotein (AFP) (57.4%) in HCC patients reached 77.0%. HCC patients with multiple tumour foci (7.53 ng/ml; 1.40-29.18 ng/ml) had significantly higher sFas levels than did patients with a solitary tumour (2.70 ng/ml; 0.14-19.0 ng/ml) (P = 0.003). In all of the sFas-positive patients with a solitary tumour, surgical removal of the tumour reduced sFas levels to the negative in the first post-op week. These findings suggest that sFas may be closely linked with HCC and may be a candidate for a clinical parameter for HCC.

Enhancing effect of N-dodecyl-2-pyrrolidone on the percutaneous absorption of 5-fluorouracil derivatives.

The enhancing effects of N-dodecyl-2-pyrrolidone (NDP) on the percutaneous absorption of doxifluridine (DOX), 5-fluorouracil (5-FU), tegafur (TEG) and carmofur (CAR) were examined using an in vitro penetration technique and rat skin. Phosphate buffered isotonic saline (PBS), propylene glycol (PG) and PG containing 0.4M NDP (PGNDP) were applied as the donor solution. The correlation between the n-octanol/water partition coefficients and the permeability coefficients of DOX, 5-FU and TEG was investigated using both logarithmic plots. It was determined that the permeability coefficients are significantly correlated with their n-octanol/water partition coefficients on PBS. This result suggested that the non-polar stratum corneum lipid lamella in the skin might act as a rate limiting step on the skin penetration of DOX, 5-FU and TEG. The permeability coefficient of DOX, 5-FU and TEG was increased on PGNDP. The enhancing effect of NDP on the permeability coefficient was more effective at higher hydrophilic drugs, the values of the permeability coefficient had almost the same values on PGNDP and the dependency of the permeability coefficient on the n-octanol/water partition coefficient disappeared in the presence of NDP. These results indicated that the enhancing effect of NDP on the percutaneous absorption of DOX, 5-FU and TEG might be closely related to the perturbation of stratum corneum lipid lamella. Since it has been well recognized that CAR is decomposed into 5-FU in neutral and alkaline solution, the decomposition rate of CAR was measured using PBS solution and was found to be very rapid (Kd = 3.17 h-1, t1/2 = 13.1 min). The total concentrations of CAR plus 5-FU in the acceptor compartment were used to determine the permeability coefficient of CAR. The obtained value of the permeability coefficient of CAR on PG was almost the same as that of TEG on PG (CAR: 1.11 x 10(-3) cm/h, TEG: 1.24 x 10(-3) cm/h), while that of CAR on PGNDP was smaller than that of TEG on PGNDP (CAR: 6.06 x 10(-3) cm/h, TEG: 1.24 x 10(-2) cm/h). To determine the lipophilic property of CAR, the lipophilic index (log k') was measured by HPLC. The value of the lipophilic index of CAR was 92 times higher than that of TEG. These results indicated that CAR is a higher lipophilic compound, and the smaller value of the permeability coefficient of CAR compared with that of TEG on PGNDP might be caused by the strong binding of CAR to the rat skin (dermis). The dermis might act as a rate limiting step on the skin penetration of CAR, and the percutaneous absorption of CAR might be controlled by both the stratum corneum and the dermis.

A human monoclonal antibody which inhibits the coaggregation activity of Porphyromonas gingivalis.

A B-cell line producing a human monoclonal antibody (HuMAb) against a recombinant 40-kDa outer membrane protein (OMP) of Porphyromonas gingivalis was constructed by in vivo immunization of a severe combined immunodeficiency C.B.-17/Icr mouse, which had been injected with human peripheral blood lymphocytes, with recombinant 40-kDa OMP and subsequent Epstein-Barr virus immortalization of B cells isolated from the spleen of the mouse. This HuMAb inhibited coaggregation between P. gingivalis vesicles and Actinomyces naeslundii cells.