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The efficacy of the local application of recombinant human fibroblast growth factor-2 (FGF-2) in periodontal regeneration has been investigated. In this study, a randomized, double-blind, placebo-controlled clinical trial was conducted in 253 adult patients with periodontitis. Modified Widman periodontal surgery was performed, during which 200 µL of the investigational formulation containing 0% (vehicle alone), 0.2%, 0.3%, or 0.4% FGF-2 was administered to 2- or 3-walled vertical bone defects. Each dose of FGF-2 showed significant superiority over vehicle alone (p < 0.01) for the percentage of bone fill at 36 wks after administration, and the percentage peaked in the 0.3% FGF-2 group. No significant differences among groups were observed in clinical attachment regained, scoring approximately 2 mm. No clinical safety problems, including an abnormal increase in alveolar bone or ankylosis, were identified. These results strongly suggest that topical application of FGF-2 can be efficacious in the regeneration of human periodontal tissue that has been destroyed by periodontitis.

SUMMARYThe immunoglobulin receptor FcγRIIIa (CD16) is distributed on natural killer (NK) cells, macrophages, and γδ T cells, and is polymorphic. FcγRIIIa-158V has a higher affinity for both monomeric and immune complexed IgG1, IgG3, and IgG4 than IIIa-158F. We determined FcγRIIIa-158V/F genotypes of Japanese patients with adult periodontitis. A significant over-representation of FcγRIIIa-158F was found in patients with recurrence, compared with patients without recurrence, making FcγRIIIA a candidate gene for recurrence risk of adult periodontitis.

SUMMARY In an attempt to clarify the immunobiological events featuring periodontitis lesions of AIDS patients in the late stage of the disease, peripheral blood (PB) and gingival crevicular fluid (GCF) leucocytes from periodontitis lesions of 23 late-stage AIDS patients were analysed by three-colour flow cytometry for detection and identification of intracytoplasmic p24+ cell fractions. The cells were reacted with CD14 and CD68 for mononuclear phagocytes or with CD4 and CD14 for Th cells, then with anti-p24 MoAb. To detect HIV proviral sequences and intracellular p24 RNA sequences, genomic DNA and cellular RNA from leucocytes were extracted for semi-nested polymerase chain reaction (PCR) amplification. CD68+/p24+ and CD14+/CD68+/p24+ fractions were larger in GCF than in PB (P < 0·0001; P < 0·003). CD14+/p24+ fraction was lower in GCF than in PB (P < 0·05). The fluorescence intensities (FI) for intracellular p24 in CD68+ and CD14+/CD68+ cells were higher in GCF than in PB (P < 0·003; P < 0·02), whereas those of CD14+ macrophages did not differ. The p24 FI of CD68+ macrophages in GCF correlated with CD4+ lymphocyte counts in PB (P < 0·005). p24 FI levels of CD14+ monocytes in GCF and PB significantly correlated (P < 0·02), whereas that of CD68+ macrophages did not. PCR and reverse transcriptase (RT)-PCR of cellular DNA and RNA yielded positive signals, demonstrating viral integration and production in GCF leucocytes. These results show that periodontitis lesions in AIDS patients can be characterized by a rapid macrophage turnover, and these HIV-infected macrophage exudates in GCF may be considered as a within-mouth source of virus.

Background There is little evidence on prediction of clinical response to biologics in patients with RA. Recently, it has been suggested that clinical response to tumor necrosis factor (TNF) inhibitors was related to periodontal conditions, which might be affected by infection with Porphyromonas gingivalis ( P.g. ). Additionally, serum antibody responses to P. g were associated with RA and periodontitis.Newly established test of antibody against hemin binding protein 35 (HBP) of P.g. , which has an ability specifically bind to P.g. containing protein HBP, can be available. Objectives To evaluate whether serum antibody responses to P.g. antigens and periodontal conditions are associated with clinical response to biologics in patients with RA. Methods 20 patients with severe RA enrolled in this study were treated with biologics according to the usual regimen. Clinical background and disease parameters were assessed at entry. DAS28-CRP was evaluated at 6 months (reassessment) after the initiation of biologics. Periodontal conditions were also assessed at entry. Serum levels of antibodies against P.g. sonicated extracts (SE) and HBP of P.g. were determined by enzyme-linked immunsorbent assay, respectively. Results Their mean (SD) age was 57.2 (13.4) years. Patients were predominantly women (85%) with mean disease duration of 8.2 (6) years.10 patients were treated with TNF-i, 7 with IL-6 blocker and 3 with CTLA4-Ig, respectively. Most patients had active disease with DAS28-CRP 4.2 (0.9) at baseline, and showed an improvement of DAS28-CRP 2.87 (0.82) at reassessment. Seven patients (35%) achieved remission (DAS28-CRP

Human FcγRIIb is an immunoglobulin G (IgG) receptor that inhibits the activation of B lymphocytes through cross-linking with the B-cell receptor via immune complexes. This function acts as a negative regulator of antibody production. Our previous studies have demonstrated the gene polymorphisms in FcγRIIb to be associated with periodontitis. In this study, we presented a polymorphism--FcγRIIB-nt645+25A/G (rs2125685)--in intron 4 and analyzed its functional relevance to periodontitis. We examined whether the FcγRIIB-nt645+25A/G polymorphism is associated with periodontal parameters, the IgG response to the periodontopathic bacterium Porphyromonas gingivalis and/or the expression level of FcγRIIb on peripheral B lymphocytes.Thirty-two patients with chronic periodontitis were genotyped with nested PCR and by direct sequencing of genome DNA. The levels of serum IgG and of specific IgG subclasses for P. gingivalis sonicate and for the recombinant 40-kDa outer membrane protein (OMP) were determined. The expression levels of FcγRIIb on peripheral B lymphocytes from 19 healthy donors were measured by flow cytometry.Patients with the FcγRIIB-nt645+25AA genotype showed significantly higher mean clinical attachment levels compared to patients with the FcγRIIB-nt645+25GG genotype (p = 0.003) and a significantly lower IgG response to P. gingivalis sonicate and to the 40-kDa OMP. The expression levels of FcγRIIb protein on the cell surface in peripheral B lymphocytes were higher in healthy donors with the FcγRIIB-nt645+25AA genotype than in those with the FcγRIIB-nt645+25GG genotype (p = 0.03).The higher expression levels of FcγRIIb in subjects with the FcγRIIB-nt645+25AA genotype may induce a lower level of production of IgG against P. gingivalis and therefore more severe periodontitis.

The gram-negative anaerobe Porphyromonas gingivalis has been implicated as an important pathogen in the development of adult periodontitis, and its colonization of subgingival sites is critical in the pathogenic process. We previously identified a 35 kDa surface protein (hemin binding protein 35; HBP35) from P. gingivalis that exhibited coaggregation activity, while additional analysis suggested that this protein possessed an ability to bind heme molecules. For development of passive immunotherapy for periodontal diseases, human-type monoclonal antibodies have been prepared using HBP35 as an antigen in TransChromo mice. In the present study, we focused on a single antibody, TCmAb-h13, which is known to inhibit heme binding to recombinant HBP35. The aim of our investigation was to clarify the redox-related function of HBP35 and consider the benefits of human-type monoclonal antibodies.To examine the antigen recognition capability of TCmAbs with immunoblotting and Biacore techniques, we used the native form as well as several Cys-to-Ser variants of recombinant HBP35.We found that the redox state of recombinant HBP35 was dependent on two Cys residues, (48) C and (51) C, in the thioredoxin active center (WCGxCx). Furthermore, TCmAb-h13 recognized the reduced forms of recombinant HBP35, indicating its inhibitory effect on P. gingivalis growth.Hemin binding protein 35 appears to be an important molecule involved in recognition of the redox state of environmental conditions. In addition, TCmAb-h13 had an inhibitory effect on heme binding to recombinant HBP35, thereby interfering with P. gingivalis growth.

Gene expression is related to the pathogenesis of periodontitis and plays a crucial role in local tissue destruction and disease susceptibility. The aims of the present study were to identify the expression of specific genes and biological pathways in periodontitis-affected gingival tissue using microarray and quantitative real-time RT-PCR analyses.Healthy and periodontitis-affected gingival tissues were taken from three patients with severe chronic periodontitis. Total RNAs from six gingival tissue samples were used for microarray analyses. Data-mining analyses, such as comparisons, gene ontology and pathway analyses, were performed and biological pathways with a significant role in periodontitis were identified. In addition, quantitative real-time RT-PCR analysis was performed on samples obtained from 14 patients with chronic periodontitis and from 14 healthy individuals in order to confirm the results of the pathway analysis.Comparison analyses found 15 up-regulated and 13 down-regulated genes (all of which showed a change of more than twofold in expression levels) in periodontitis-affected gingival tissues. Pathway analysis identified 15 up-regulated biological pathways, including leukocyte transendothelial migration, and five down-regulated pathways, including cell communication. Quantitative real-time RT-PCR verified that five genes in the leukocyte transendothelial migration pathway were significantly up-regulated, and four genes in the cell communication pathway were significantly down-regulated, which was consistent with pathway analysis.We identified up-regulated genes (ITGB-2, MMP-2, CXCL-12, CXCR-4 and Rac-2) and down-regulated genes (connexin, DSG-1, DSC-1 and nestin) in periodontitis-affected gingival tissues; these genes may be related to the stimulation of leukocyte transendothelial migration and to the the impairment of cell-to-cell communication in periodontitis.

Recently, numerous studies have investigated the association of preterm birth with periodontitis. FcγRIIb is a human low-affinity receptor for immunoglobulin G (IgG). We have previously demonstrated single nucleotide polymorphisms (SNPs) of FcγRIIb to be associated with periodontitis and the serum-specific IgG level against periodontopathic bacteria. In this study, we investigated whether FcγRIIB gene polymorphisms were associated with periodontitis and/or pregnancy outcome.We assessed the periodontal conditions of 122 Japanese pregnant women within 5 d of delivery, and polymorphisms in FcγRIIB and in other Fcγ receptors were detected from the genomic DNA. Using clinical and genomic data, we analyzed the relationship between periodontitis, preterm birth and Fcγ receptor polymorphisms.A significant difference was observed in the distribution of FcγRIIB-nt645+25A/G (rs2125685) between preterm and term birth groups, with a higher prevalence of nt645+25AA in the preterm birth group (p = 0.032). Additionally, the FcγRIIB-nt645+25GG carrier showed significantly higher results for the prevalence of periodontitis (p = 0.048), mean pocket depth (p = 0.021), mean clinical attachment level (p = 0.010), percentage of sites with pocket depth ≥ 4 mm (p = 0.005) and percentage of sites with clinical attachment level ≥ 3 mm (p = 0.007) than the AA carrier. An association between preterm birth and periodontitis was not observed in this study.These findings suggest that FcγRIIB-nt645+25AA carriers are more likely to experience preterm birth than FcγRIIB-nt645+25AG and GG carriers. Also, women with FcγRIIB-nt645+25G exhibited a greater tendency to have periodontitis than those with nt645+25A.

Neutrophils are essential in host defense against periodontopathic bacteria. Immunoglobulin G Fc receptor IIIb (FcγRIIIb) is a neutrophil-specific receptor for immunoglobulin G and bears the functional NA1-NA2 polymorphism. Accumulating evidence suggests a significant association between FcγRIIIb gene polymorphism and periodontitis. In this study, we employed a proteomic approach to evaluate the relevance of FcγRIIIb polymorphism to protein expression profiles of neutrophils.Neutrophils were collected from ten healthy subjects whose FcγRIIIb genotypes were determined by allele-specific PCRs. Expressions of proteins induced by interaction via FcγRIIIb were examined between the FcγRIIIb genotypes with two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins that were significantly different in expression levels between the FcγRIIIb genotypes were determined with computer image analysis, and identified with mass spectrometry and protein databases.A total of 757 protein spots were observed in the two-dimensional electrophoretograms of neutrophils from five FcγRIIIb-NA1/NA1 and five FcγRIIIb-NA2/NA2 donors. A statistical analysis revealed that the expression levels of five proteins were significantly different between the FcγRIIIb genotypes (p0.05). The FcγRIIIb-NA1/NA1 neutrophils exhibited two spots that were significantly underexpressed (protein-arginine deiminase type-4 and annexin VI) and three spots that were significantly overexpressed (Cdc42hs-Gdp complex, myosin light chain 12A and coactosin-like 1) when compared with FcγRIIIb-NA2/NA2 neutrophils. The same expression profiles of protein-arginine deiminase type-4 were obtained by ELISA.Differential protein expression profiles were observed in neutrophils between FcγRIIIb genotypes.

Our previous study demonstrated that the gene expression of FOXP3, a characteristic marker for CD4(+) CD25(+) regulatory T cells in mice, is upregulated more in periodontitis than in gingivitis at the messenger RNA (mRNA) level. Furthermore, most of the T-cell clones established from periodontitis lesions expressed FOXP3 mRNA. However, role of the FOXP3(+) gingival T cells has not been elucidated.The phenotype of FOXP3-expressing cells in periodontitis lesions was determined immunohistochemically. CD4(+) FOXP3(+) gingival T-cell clones were established from three patients with advanced periodontitis by using immunomagnetic beads. Gene expression and phenotype analyses were performed by reverse-transcription polymerase chain reactions and flow cytometry, respectively. The effect of CD4(+) FOXP3(+) T-cell clones on the proliferative response of CD4(+) CD25(-) T cells was examined by [(3)H]thymidine incorporation.FOXP3 expression was found in some CD4(+) T cells and CD25(+) cells but not in CD8(+) T cells by immunohistochemistry. In spite of a substantial expression of the CD25 gene, the expression level of membrane CD25 on the CD4(+) FOXP3(+) gingival T-cell clones was low. While peripheral blood CD4(+) CD25(+) FOXP3(+) cells suppressed the proliferation of CD4(+) CD25(-) T cells, the CD4(+) CD25(low) FOXP3(+) gingival T-cell clones enhanced the proliferation significantly.Our study makes it evident that most, if not all, of the FOXP3(+) T cells in periodontitis lesions can be considered to be effector T cells. The effector activity of the gingival T-cell clones could be attributable to the low level of membrane CD25 expression. Further studies are clearly needed to clarify the role of these T cells and their unique characteristics in the pathogenesis of periodontal disease.

The nuclear magnetic resonance of59Co nuclei in magnetic domains of RCo3(R:Y, Nd, Sm, Gd, Tb, Dy and Ho) has been measured under external fields up to about 50 kOe at 4.2 K. To assign the observed NMR signals to each Co site, the59Co nuclear magnetic resonance of R(Co1−xNix)3 and R(Co1−xFex)3 has also been measured under the same conditions. The results of NMR studies show that the cobalt atoms at the 6c site in the light R compounds(YCo3, NdCo3 and SmCo3) and these at the 3b site in the heavy R compounds(GdCo3, TbCo3 and HoCo3) have a large orbital contribution.

Although T cells have been implicated in the pathogenesis and are considered to be central both in progression and control of the chronic inflammatory periodontal diseases, the precise contribution of T cells to the regulation of tissue destruction has not been fully elucidated. Current dogma suggests that immunity to infection is controlled by distinct T helper 1 (Th1) and T helper 2 (Th2) subsets of T cells classified on the basis of their cytokine profile. Further, a subset of T cells with immunosuppressive function and cytokine profile distinct from Th1 or Th2 has been described and designated as regulatory T cells. Although these regulatory T cells have been considered to maintain self-tolerance resulting in the suppression of auto-immune responses, recent data suggest that these cells may also play a role in preventing infection-induced immunopathology. In this review, the role of functional and regulatory T cells in chronic inflammatory periodontal diseases will be summarized. This should not only provide an insight into the relationship between the immune response to periodontopathic bacteria and disease but should also highlight areas of development for potentially new therapeutic modalities.

Although T cells have been implicated in the pathogenesis and are considered to be central to both their progression and control of chronic inflammatory periodontal diseases, the precise contribution of T cells to tissue destruction has not been fully clarified. Recently, interleukin (IL)-17 and receptor activator of Nuclear factor kappaB NF-kappaB ligand (RANKL) have received much attention as a result of their proinflammatory and bone metabolic roles, respectively. We therefore investigated the effect of outer membrane protein (OMP) from Porphyromonas gingivalis (P. gingivalis) on the expression of IL-17 and RANKL in peripheral blood mononuclear cells (PBMCs) and compared these between gingivitis and periodontitis, which are representative of stable and progressive lesions, respectively. The in situ expression of these molecules was also examined. P. gingivalis OMP stimulated PBMCs to express IL-17 at both the mRNA and protein level. Although the mean expression of mRNA was not different between the two groups, the mean level of IL-17 in the culture supernatants was higher in gingivitis patients than in periodontitis patients. However, the frequency of IL-17-positive samples was higher in the periodontitis patients. This stimulatory effect was not evident for RANKL expression in either periodontitis or gingivitis patients. In gingival tissue samples, IL-17 mRNA was detected in gingivitis more frequently than in periodontitis. The expression of RANKL mRNA was much lower than that of IL-17 in terms of both level and frequency. These results suggest that IL-17 but not RANKL may be involved in the pathogenesis of periodontal diseases. However, there may be negative regulatory mechanisms for IL-17 in gingivitis.

Gingivitis and periodontitis have distinct clinical and immunopathological characteristics. We have previously demonstrated that T cells infiltrating periodontitis lesions recognize a restricted repertoire of antigens or antigenic epitopes. However, the clonality of T cells in the gingivitis lesion is not known. Therefore, we carried out a clonal analysis of T cells infiltrating gingivitis lesions using combined reverse transcription-polymerase chain reaction and single-strand conformation polymorphism (SSCP) analysis. As with periodontitis lesions, SSCP analysis demonstrated the emergence of a number of distinct bands suggesting clonal accumulation in the gingivitis lesion. Although the mean number of distinct bands in gingival tissue was significantly higher than that in peripheral blood mononuclear cells, numerical analysis clearly demonstrated that there was no difference in the total number of bands in gingival tissue specimens between the different disease types. Although there were slight variations in the number of distinct bands in each Vbeta family, there was no significant difference between gingivitis lesions and periodontitis lesions. These results demonstrate that antigen-specific T-cell responses also take place in gingivitis lesions. It remains to be determined, however, what role these antigen-specific T cells play and what antigens the T cells recognize in the pathogenesis of periodontal disease.

Differential gene expression was investigated in neutrophils stimulated with N-formyl-methionyl-leucyl-phenylalanine using RNA fingerprinting by arbitrarily primed polymerase chain reaction (RAP-PCR). The cells were isolated from 3 groups of subjects: patients with generalized aggressive periodontitis (Aggressive-P. n = 6), generalized chronic periodontitis (Chronic-P, n = 6) and healthy controls (H, n = 8). Our results show that 37 genes were upregulated. while 27 genes were down-regulated in all Aggressive-P neutrophils by using RAP-PCR with 45 primer pairs. Reverse transcription-PCR analyses revealed that mRNA levels were significantly different (p0.05) for heat shock transcription factor 4b (HSF4b) gene. Kruppel-like zinc finger transcription factor 9 (Zf9) and muskelin genes. HSF4b was greater in neutrophils from Aggressive-P compared to groups H and Chronic-P. Zf9 and muskelin genes were lower in Aggressive-P compared to the H groups, but no significant difference was noted compared to the Chronic-P group. The control genes, IL-1beta and VEGF genes, were expressed at a significantly higher level in Aggressive-P and Chronic-P than H (p.01, p0.05). In conclusion, the RAP-PCR technique used in this study enabled us to identify 3 Aggressive-P related genes, which had not been reported previously. Neutrophil functions in Aggressive-P patients are suggested to be altered by regulatory factors of the immune system including HSF4b (transcription factor), Zf9 (activator of TGF-beta) and muskelin (cellular adhesion).

Recent evidence suggests that molecular mimicry between bacterial and human heat shock protein 60 (hsp60) is involved in various conditions of autoimmune and infectious diseases. Many periodontopathic bacteria have been reported to express GroEL-like protein that is homologous to human hsp60. In this study, the presence of antibodies to the hsp60 of Actinobacillus actinomycetemcomitans in the sera of periodontitis patients and periodontally healthy control subjects was evaluated by enzyme-linked immunosorbent assay using a recombinant A. actinomycetemcomitans GroEL as an antigen. Furthermore, their cross-reactivity with Escherichia coli GroEL and Mycobacterium bovis BCG hsp65 was examined. The mean values of antibody were 0.624 (range 0.088-1.113) and 0.728 (range 0.217-1.296) in control subjects and periodontitis patients, respectively. The antibody levels to A. actinomycetemcomitans after absorption with E. coli GroEL and M. bovis BCG clearly decreased in both control subjects and periodontitis patients. The remaining antibody levels to A. actinomycetemcomitans GroEL after absorption with M. bovis BCG hsp65 were higher than those with E. coli GroEL, indicating higher cross-reactivity with E. coli GroEL. These results suggest that not only periodontitis patients but also periodontally healthy subjects may be infected with A. actinomycetemcomitans but that the part of the antibody could be derived from the cross-reactivity with E. coli GroEL. Any relationship of the antibody to the disease, however, remains to be determined.

Differential gene expression was examined in human neutrophils stimulated with lipopolysaccharide from Porphyromonas gingivalis (P. gingivalis-LPS) using RNA fingerprinting by arbitrarily primed polymerase chain reaction (RAP-PCR). LPS from Escherichia coli (E. coli-LPS) was used as control. More than 200 differently expressed transcripts were found in 8 subjects showing differential regulation at the transcriptional level. Densitometric analyses revealed that 42-100 genes were upregulated, while 53-116 genes were downregulated by P. gingivalis-LPS compared with E. coli-LPS. The results of sequencing identification showed the presence of supervillin (SVIL) and vascular endothelial growth factor (VEGF) genes in the clones which were upregulated by P. gingivalis-LPS. Consequently, semiquantitative analyses proved that the level of mRNA for SVIL and VEGF were significantly higher in P. gingivalis-LPS-stimulated neutrophils than in other bacterial (E. coli, Actinobacillus actinomycetemcomitans, Prevotella intermedia) LPS- or synthetic lipid A-stimulated neutrophils. Our findings suggest that an elevated mRNA expression for SVIL could be associated with impaired function of neutrophils when stimulated by P. gingivalis-LPS. Further, the VEGF mRNA over-expression might be related to the pathogenesis of P. gingivalis-associated periodontitis. The RAP-PCR technique used in this study enabled us to identify a number of P. gingivalis-LPS regulated genes which hitherto have not been reported.

Immunoglobulin G Fc receptor IIIb (FcgammaRIIIb) is constitutively expressed on neutrophils, and has three allelic forms: FcgammaRIIIb-NA1, FcgammaRIIIb-NA2, and FcgammaRIIIb-SH. We identified two Japanese subjects in whom an A to G substitution at nt 221 changes asparagine (N) to serine (S) at amino acid position 45 in the FcgammaRIIIb-NA2 gene. FcgammaRIIIb-NA2-specific monoclonal antibodies (GRM1 and PEN1) did not bind to mutant neutrophils, which lack an N-linked glycosylation site. Furthermore, IgG3-mediated neutrophil phagocytosis by mutant was slightly increased as compared to wild-type donors (Note).

The integrity of connective tissues surrounding dental implants may be influenced by a balance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). The purpose of this study was to provide an overall assessment of TIMP-1, MMP-1 and -8 levels as well as collagenase activities during the wound healing process after implantation and in peri-implantitis lesions. Peri-implant crevicular fluid (PICF) was sampled with sterile paper strips from 10 osseointegrated implants of 6 subjects. Ten implants from 6 patients affected with peri-implantitis were also assessed. Gingival crevicular fluid (GCF) from 11 periodontitis-affected patients and 10 healthy volunteers served as controls. TIMP-1 and MMP-1 and -8 protein levels in the PICF were measured by ELISA, and active and APMA-activatable collagenase activities were determined by functional assays using image-analysis after SDS-PAGE. The experiment showed a significant increase in the TIMP-1 level at 1 week after implantation as compared with that in GCF from healthy periodontium. Four weeks after implantation it had reached the same level as that in the GCF of healthy subjects. The data has also disclosed a higher post-implantation collagenase activity level at 1 week than at weeks 2, 4, and 12. This may be due to the increase in MMP-1 and -8. Furthermore, peri-implantitis and periodontitis were shown to be similar inflammatory lesions in respect to MMP-1 and -8 and collagenase activities, even though the TIMP-1/MMP-1 + MMP-8 ratio was significantly lower in peri-implantitis than in periodontitis. In conclusion, the overproduction of TIMP-1 in the wound area after implantation could, to some extent, inhibit excessive tissue destruction and degradation of the neo-matrix in wound repair due to MMPs.

During surgical treatment of periodontal disease, enamel matrix derivative (EMD) is topically applied as a substitute for extracellular matrix in order to facilitate regeneration of damaged periodontal tissue. However, the mechanism for EMD action is poorly understood. We have now examined the effects of EMD on the proliferation of oral epithelial (SCC25) cells in vitro. After 3 days of treatments, EMD (25 100 microg/ml) dose-dependently inhibited cell division and concomitantly arrested cell cycle at the G1 phase. Prior to this inhibition, EMD significantly up-regulated p21WAF1/cip1, a cyclin-dependent kinase inhibitor, induced G1-arrest, and inhibited DNA synthesis. In addition, EMD down-regulated expression of cytokeratin-18 (CK18) protein, which was most due to decreased production, but less to increased degradation. However, EMD did not discernibly increase the number of apoptotic cells over 8 days of treatment. These findings indicate (1) that EMD acts as a cytostatic agent, rather than a cytotoxic agent, on epithelial cells, and (2) that this anti-proliferative action is probably due to p21WAF1/cip1-mediated G1-arrest. Furthermore, our in vitro cellular data clearly verify and provide an explanation for the clinical observation that EMD application suppresses the down-growth of junctional epithelium onto dental root surfaces, a process that frequently interferes with the formation of new connective tissue attachments.

Polymorphonuclear neutrophils (PMNs) are essential in host defense against periodontopathic bacteria such as Porphyromonas gingivalis. The uptake of immunoglobulin G (IgG)-opsonized bacteria via IgG Fc receptors (Fc gamma R) on PMN constitutes a central defense mechanism in periodontium. Fc gamma RIIIb is the most abundantly expressed Fc gamma R on PMN and is functionally polymorphic. The Fc gamma RIIIb-NA1 and IIIb-NA2 allotypes interact differently with IgG1- and IgG3-opsonized particles. We recently showed recurrence rates of adult periodontitis (AP) to be higher in patients carrying at least 1 Fc gamma RIIIb-NA2 allele. In this study we evaluated the functional relevance of the Fc gamma RIIIb polymorphism to anti-P. gingivalis PMN effector functions. Our results showed Fc gamma RIIIb-NA2-carrying PMN from both patients with AP and healthy controls to be less efficient in phagocytosis and induction of oxidative burst upon interaction with IgG1- and IgG3-opsonized P. gingivalis. These functional differences between Fc gamma RIIIb-NA1 and IIIb-NA2 were observed in the presence of CD32-blocking antibody fragments, but not upon blocking CD16. Moreover, PMNs from AP patients exhibited increased Fc gamma RIIIb-allelic differences in IgG3-induced oxidative burst compared to control PMNs. These results support the concept that Fc gamma RIIIb heterogeneity may influence the clinical course of AP.

DNA binding activity of NF-kappa B and AP-1 were examined in neutrophils stimulated with LPS purified from P. gingivalis, a major pathogenic bacteria of periodontitis lesion. Porphyromonas gingivalis LPS enhanced the activity reaching a peak at a concentration of 500 ng/ml in the absence of serum. The NF-kappa B activation stimulated with 10 ng/ml of P. gingivalis LPS was suppressed approximately 44% by treatment of neutrophils with anti-CD14 antibody under the presence of serum. Increase in the steady-state IL-8 mRNA level was concomitantly observed by stimulation of neutrophils with 500 ng/ml of P. gingivalis LPS under the absence of serum. These results indicate that P. gingivalis LPS activates NF-kappa B and AP-1 in both serum-dependent and -independent manners, followed by increased IL-8 transcription in neutrophils, and suggested a role for P. gingivalis LPS in IL-8 synthesis by neutrophils in inflamed gingiva and GCF.

A previous study has demonstrated that complement receptors on the surface of polymorphonuclear leucocytes (neutrophils) in gingival crevicular fluid significantly increased compared with those in autologous peripheral blood obtained from periodontitis-affected subjects. The present study attempted to determine the mRNA levels of complement receptor types 1 and 3 (CR1, CR3) on neutrophils in gingival crevicular fluid using reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. Gingival crevicular fluid samples were obtained from 11 adult periodontitis patients by gingival crevicular washing, and venipunctured peripheral blood was used as a control. RT-PCR analysis was performed using the primer sets for CR1, CR3 and beta-actin. Digoxigenin-labelled RNA probes were synthesized from RT-PCR products for in situ hybridization. Both CR1 and CR3 mRNA levels relative to beta-actin were significantly lower in crevicular fluid neutrophils than in peripheral blood neutrophils (crevicular fluid-CR1, 32.75 +/- 22.93%, peripheral blood-CR1; 65.30 +/- 43.25%, p0.005; crevicular fluid-CR3; 9.09 +/- 5.34%, peripheral blood-CR3; 30.14 +/- 18.80%, p0.005). In in situ hybridization, a greater majority of neutrophils showed positive CR1 and CR3 mRNA expression, while only a few neutrophils showed positive signals in gingival crevicular fluid. Data in the present study suggest that increased expression of complement receptors on the neutrophil cell surface appears to be unrelated to de novo synthesis.

As a diagnostic test, "Periocheck" can detect the N-carbobenzoxyglycyl-glycy-arginyl peptidase that is produced by Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus. The aim of this study was to clarify the relationship between peptidase activity and attachment loss. After Phase 1 and surgical therapy, a total of 111 sites from 47 adult periodontitis patients were divided into four groups according to peptidase activity (trypsin unit, TU): A,0.1 TU; B, 0.1-0.2 TU; C and Dor = 0.2 TU. All sites in groups A, B, and C were untreated, whereas both subgingival 3% hydrogen peroxide irrigation and 2% minocycline application were undertaken every 45 days throughout the experiment in group D. All subjects were recalled at 3-month intervals. Peptidase activity and clinical assessments were measured for the 18-month period. Significant attachment loss associated with high values of the peptidase activity was found through the experimental period in groups B and C. In contrast, no obvious change of attachment loss was found in groups A and D following low peptidase activity at 6, 12, and 18 months. The mean attachment loss throughout the 18-month period was 0.22 mm in group A, 1.04 mm in group B, 1.53 mm in group C, and -0.35 mm in group D. Probing depth and percentages of bleeding on probing significantly increased in group C, whereas they decreased in group D. This peptidase test displayed a 77.8% sensitivity and 68.6% specificity regarding the detection ofor = 1 mm attachment loss with a cut-off value of 0.1 TU. Multiple linear regression analysis showed a close relationship between peptidase activity and predictable attachment loss within a 12-month period. These findings suggest that this peptidase test is useful in identifying the risk sites for predictable attachment loss.

A 2-year and 5-month-old boy was admitted to Okaya municipal hospital because of low grade fever and reddish-brown urine soon after an outside walk in November, 1994. Direct Coombs test was negative, but indirect Coombs test positive. Both sugar water test and Ham test were negative. A diagnosis of paroxysmal cold hemoglobinuria (PCH) was made by Donath-Landsteiner (D-L) test which showed the presence of a high amount of anti-P specific IgG and IgM of D-L antibody. Serological tests for syphilis were negative. Cold agglutinin titer and mycoplasma antibody titer was X 128 and X 80, respectively. A bone marrow specimen exhibited pronounced hemophagocytosis. Serum INF-gamma and M-CSF level were normal (less than 5 pg/ml and 1007 units/ml, respectively). These results suggest that hemophagocytosis in this case is not due to hemophagocytic syndrome.

TGF-beta 1-coated beta-TCP pellets were grafted in experimental defects of rat calvariae to study the effects on new bone formation.The grafted sites were evaluated by light microscopy using hematoxylin-eosin (H-E) staining for histology and detection of alkaline phosphatase (ALPase) and tartrate-resistant acid phosphatase (TRACPase) activities to demonstrate osteoblastic and osteoclastic cells. Confocal laser scanning microscopy (CLSM) was performed for morphometry of newly formed bone.H-E sections showed more new bone formation in sites grafted with TGF-beta 1-coated beta-TCP pellets (experimental sites) than those with beta-TCP pellets only (control sites). TRACPase-positive and ALPase-positive cells at experimental sites were more frequent than at control sites. The bone formation rate calculated by computerized CLSM pixel image analysis showed more new bone formation at the experimental sites than at control sites (3.4 +/- 0.8% vs 9.3 +/- 1.7% on week 2 and 11.8 +/- 2.1% vs 39.8 +/- 10.9% on week 4).TGF-beta 1-coated beta-TCP pellets promote new bone formation and may be a useful modality in synthetic bone grafting.

We have previously reported that the Periocheck test offers a rapid, simple periodontal diagnostic tool by detecting peptidase activity specifically attributed to Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus. Relationships between the peptidase activity detected by the Periocheck test and clinical measures were investigated. Fifty-seven Periocheck-positive sites selected from 27 patients with adult periodontitis were subjected to scaling and root planing. Two weeks later, a Periocheck test was undertaken in the test sites. Two groups were then determined, one composed of 40 Periocheck-positive sits, and the other consisting of 17 Periocheck-negative sites. All sites were re-examined at 6, 10, 14 and 18 weeks using both the Periocheck test and clinical measures. On week 18, the negative group displayed a significant decrease in probing pocket depth (PD) and a significant attachment level (AL) gain (2.1 and 1.2 mm, respectively), while the positive group showed a slight decrease in PD and AL gain (0.9 and 0.3 mm, respectively). The differences between negative and positive groups in PD and AL became statistically significant by the tenth week. Improvement of gingival index (GI) and bleeding on probing (BOP) was more apparent in the negative group. The detection of intrapocket microbiological status by the Periocheck test preceded the changes in PD, AL, GI, and BOP after periodontal therapy. In conclusion, the Periocheck test may provide a promising chairside monitoring tool for effectively evaluating therapies associated with scaling and root planing.

Polymorphonuclear leukocytes (PMNLs) are the most numerous cell population among the cellular infiltrates in gingival crevicular fluid (GCF) and play important roles in the host-defensive system in the gingival crevices. We determined the percentage of neutrophils, eosinophils and basophils in total PMNLs by light microscopic observation using Randolph-methylene blue staining, then assessed flow cytometric differences in the expression of CR3, Fc gamma RIII, Fc epsilon RII, LFA-1 alpha, and LFA-1 beta on PMNL in GCF and peripheral blood (PB) from 21 patients with adult periodontitis (AP) and 13 healthy donors. Percentages of basophils and eosinophils were higher in GCF than in PB. In both AP patients and healthy subjects, expression of CR3 and Fc epsilon RII was higher while Fc gamma RIII was lower in GCF than in PB. The statistical analysis showed that the expressions of Fc gamma RIII and Fc epsilon RII on GCF PMNLs were lower in AP patients than in healthy subjects. Expressions of LFA-1 alpha and beta on GCF were similar to those on PB PMNLs. PB PMNLs stimulated in vitro with Porphyromonas gingivalis culture supernatant and fMLP displayed an expression pattern of CR3, Fc gamma RIII and Fc epsilon RII on GCF PMNLs. However, C5a and IL-1 failed to induce changes in Fc gamma RIII and Fc epsilon RII. The results indicate that GCF neutrophils are activated, present enhanced adhesion and a decreased IgG-binding ability which would reflect that they are at the terminal stage of activation, and that GCF contains a larger eosinophil fraction than in PB. Moreover, these GCF eosinophils appear to be activated.

e14578 Background: The Japanese guideline for the treatment of hepatocellular carcinoma (HCC) recommends resection for cases having three tumors or less with Child-Pugh classification A or B, and t...

The effects of ovomacroglobulin (OMG), an alpha 2-macroglobulin-like protease inhibitor, were tested on periodontal surgical would healing in 60 Wistar rats. The animals were divided into two groups, one receiving topical application of 0.1% wt/wt OMG ointment and the other receiving ointment base (base). Rats were killed at one, three and seven days after surgery for histological and immunohistochemical observation. Compared with base group samples, OMG samples displayed enhanced capillary formation on anti-laminin-stained sections from day-3 specimens and a greater quantity of collagen fibers on Azan-Mallory-stained sections from day-7 specimens. Results were quantified using an automatic computerized pixel image analyzer. Hematoxylin-eosin-stained sections revealed that the length of regenerated junctional epithelium was shorter in the OMG group than in the base group. The data indicate that the application of OMG to surgical wounds accelerated fibroblast growth, collagen deposition, and capillary formation in granulation tissue. Thus, OMG could be a useful healing promoter for flap surgery.

We examined in vitro the inhibitory effects of ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis (B. gingivalis) culture supernatant, in human peripheral blood polymorphonuclear leucocytes (PMN), and in gingival crevicular fluid (GCF) from periodontitis patients. Measurement of collagenolytic activity was conducted with a CollagenoKit CLN-100 using FITC-conjugated type I collagen. The FITC-conjugated collagen was reacted with the sample in solution, and the residue was selectively degenerated at 35 degrees C and removed with ethanol. The fluorescence of the removed residue was then measured. The collagenolytic activity from B. gingivalis displayed dose dependent inhibition as high as 81.4% following addition of ovomacroglobulin at 224 micrograms/ml. The collagenolytic activity from human peripheral blood PMN showed, as a result of addition of 1,600 micrograms/ml of ovomacroglobulin, inhibition as high as 62.4%. The collagenolytic activity from human GCF, which was obtained from patients with different degrees of periodontal disease, exhibited as high as 71.0% inhibition after addition of 1,600 micrograms/ml ovomacroglobulin. Ovomacroglobulin showed almost the same level of inhibition obtained from alpha 2-macroglobulin, which was measured as a positive control. It was also recognized by SDS-PAGE that collagenolytic activity was inhibited after preincubation with added ovomacroglobulin. This collagenolytic activity, which dissolved the collagen substrate, was derived from B. gingivalis and human GCF. The above results demonstrate that ovomacroglobulin inhibits collagenolytic activity from B. gingivalis, human PMN, and human GCF.

Etude des spectres de RMN de 55 Mn en champ nul et en presence d'un champ externe atteignant 50 kOe

We investigated the ability to reconstitute the T-cell deficiency in congenitally athymic (nude; rnu/rnu) Rowett rats by intravenous injection of 10(7) heterozygous normal (rnu/+) rat thymus cells. The thymus cell-reconstituted animals showed essentially normal lymphocyte proliferation to phytohemagglutinin P and concanavalin A, normal spleen and lymph node T-lymphocyte distribution, and normal serum immunoglobulin G levels. These rats were used to study the effect of T-cell deficiency on periodontal disease. Animals with minimal oral flora were divided into three groups: nude, thymus cell-reconstituted nude, and normal rats. Immune response, gingival inflammation, and periodontal bone loss were examined in these animals. Less than 40% of the T cells recovered from the normal rat gingiva could be recovered from the nude rat gingiva. In contrast to the situation in normal or thymus cell-reconstituted rat gingiva, B cells were vastly predominant in the nude rat gingiva, with approximately four B cells for each T cell. There was increased periodontal bone loss in the nude rats compared with that in the normal rats. Thymus cell reconstitution of the nude rats was associated with decreased bone destruction. It is suggested that T cells have a regulatory function in relation to the potentially excessive B-cell response to abundant antigen and polyclonal activators in the oral cavity.

Experiments were performed to determine the effect of delayed-type hypersensitivity (DTH; cell mediated immunity) on subsequent periodontal bone loss in monoinfected (Actinobacillus actinomycetemcomitans [A actinomycetemcomitans]) gnotobiotic rats. Foot pad swelling reactions to A actinomycetemcomitans sonicate were used to monitor both immediate hypersensitivity and DTH. DTH was present in A actinomycetemcomitans immunized (I) animals when initially challenged with A actinomycetemcomitans. This DTH was maintained throughout the experimental period Sham-immunized (SI) animals did not show DTH until after 30 days of infection. The cellular infiltrate in the gingiva of immunized animals was relatively more mononuclear than the infiltrate of SI animals Serum IgG antibody to A actinomycetemcomitans was significantly elevated in I compared to SI animals. The relationship between the foot pad swelling and serum antibody levels suggested that an active Arthus type reaction was observed A actinomycetemcomitans injected rats demonstrated an Arthus-type reaction throughout the duration of the experiment SI animals only showed this reaction 30 days after immunization; the extent of swelling was always less than in the I group. Immunized rats demonstrated significantly elevated horizontal bone loss after infection for 90 days. The data suggest that a “mixed” hypersensitivity reaction to A actinomycetemcomitans occurs in presensitized rats and that the presence of this hypersensitivity can be associated with increased periodontal bone loss.