Vitronectin-Derived Peptide Promotes Reparative Dentin Formation.

Exposed dental pulp can maintain its vitality through a pulp-capping procedure with biocompatible materials, followed by reparative dentin formation. Our previous study demonstrated that a vitronectin-derived peptide (VnP-16) promotes osteoblast differentiation and concomitantly restrains osteoclast differentiation and resorptive function. In this study, we aimed to demonstrate that VnP-16 promotes odontoblast differentiation, mineralization, and reparative dentin formation in a pulp exposure model using a rat tooth. VnP-16 showed no cytotoxicity and promoted cellular behavior in human dental pulp cells, enhancing their differentiation into odontoblast-like cells and mineralization, effects that are comparable to those obtained with vitronectin. In a rat pulp exposure model, VnP-16 showed mild inflammatory responses at 2 and 4 wk or none. Mineral trioxide aggregate (MTA) demonstrated a tendency of early formation of reparative dentin at 2 wk when compared with recombinant human bone morphogenetic protein 2 (rhBMP-2) and VnP-16. However, VnP-16 induced reparative dentin formation similar to MTA and rhBMP-2 without inflammation at 4 wk. In addition, VnP-16 showed a thicker and homogeneous reparative dentin formation versus MTA and rhBMP-2. Collectively, these results suggest that VnP-16 can be a useful, direct pulp-capping agent for highly qualified reparative dentin formation by promoting cell behavior and odontoblastic differentiation of human dental pulp cells.

Kinetin enhances in vitro development of parthenogenetic and nuclear transfer porcine embryos.

Culture conditions affect the development of mammalian embryos in vitro. Kinetin belongs to the family of N(6)-substituted adenine derivates and promotes cell division, synthesis of DNA repair enzymes, superoxide dismutase activity, and ribosomal RNA transcription. We investigated the effects of kinetin on in vitro development of parthenogenetic and nuclear transfer (NT) porcine embryos. These embryos were cultured with or without kinetin in either BSA- or polyvinyl alcohol-containing medium for 7 days. mRNA expression of three developmentally important genes, HSP70, Glut-1, and poly[A] polymerase in NT embryos was analyzed. Regardless of kinetin supplementation, the proportion of blastocysts and blastocyst cells were not significantly different in parthenogenetic embryos. However, kinetin supplementation increased expansion and hatching rates in all groups. In somatic cell NT embryos, kinetin increased the proportion of embryos developed to blastocysts from 7.5% to 15.4% in medium supplemented with PVA. However, gene expression levels of HSP70, poly[A] polymerase and Glut-1 mRNA were not significantly different in NT blastocysts. The present study indicates that kinetin not only improves blastocyst expansion and cell number of parthenogenetic porcine embryos but also enhances NT porcine embryo development in a completely defined culture condition in vitro.

A novel microtube culture system that enhances the in vitro development of parthenogenetic murine embryos.

Oil is an indispensable material in micro-droplet culture; it prevents medium from evaporation, and its transparency facilitates monitoring. However, lipophilic factors in the medium can be absorbed into the oil overlay, and conversely, deleterious materials can diffuse into the medium. In the present study, we describe a novel oil-free microtube culture (MTC) system. Parthenogenetic mouse embryos were placed into 0.2-mL thin-wall flat cap PCR tubes and cultured to the blastocyst stage. Conventional drop culture was used as a control. Embryos in MTC had a higher blastocyst formation rate (89.2%) and larger population of cells in the blastocysts (92.0+/-6.9; mean+/-S.E.M.) compared with drop culture (78.3% and 74.7+/-8.1; P<0.05 for each). The large blastocyst cell population in MTC was due to higher numbers of trophectoderm (TE) cells (70.5+/-5.9 versus 53.8+/-7.4; P<0.05) rather than inner cell mass cells. The presence of more TE cells was attributed to faster development in MTC. Embryos cultured in oil-covered MTC had fewer TE cells (61.5+/-5.6) than oil-free cultures (70.5+/-5.9; P<0.05). In conclusion, oil-free MTC was an alternative to conventional micro-drops, without the deleterious effects of oil.

Regulation of osteoclast differentiation by the redox-dependent modulation of nuclear import of transcription factors.

This study sought to characterize the reduced glutathione (GSH)/oxidized GSSG ratio during osteoclast differentiation and determine whether changes in the intracellular redox status regulate its differentiation through a RANKL-dependent signaling pathway. A progressive decrease of the GSH/GSSG ratio was observed during osteoclast differentiation, and the phenomenon was dependent on a decrease in total glutathione via downregulation of expression of the gamma-glutamylcysteinyl synthetase modifier gene. Glutathione depletion by L-buthionine-(S,R)-sulfoximine (BSO) was found to inhibit osteoclastogenesis by blocking nuclear import of NF-kappaB and AP-1 in RANKL-propagated signaling and bone pit formation by increasing BSO concentrations in mature osteoclasts. Furthermore, intraperitoneal injection of BSO in mice resulted in an increase in bone density and a decrease of the number of osteoclasts in bone. Conversely, glutathione repletion with either N-acetylcysteine or GSH enhanced osteoclastogenesis. These findings indicate that redox status decreases during osteoclast differentiation and that this modification directly regulates RANKL-induced osteoclastogenesis.

Combined oral carcinogenicity of HPV-16 and benzo(a)pyrene: an in vitro multistep carcinogenesis model.

We previously immortalized normal human oral keratinocytes by transfection with recombinant HPV-16 DNA and subsequently exposed the cells to benzo(a)pyrene for 7 days. The exposure to benzo(a)pyrene modified the immortalized cells: the modified cells (HOK-16B-BaP) proliferated in an ordinary culture medium containing physiological calcium level (1.5 mM), but demonstrated only enhanced proliferation capacity without tumor formation in nude mice and failed to show in vitro anchorage-independency. In this study, we further modified the HOK-16B-BaP cells by subculturing the cells in a medium containing benzo(a)pyrene for 6 months. The cells were further modified with a chronic benzo(a)pyrene exposure and were termed HOK-16B-BaP-T cells (1) demonstrated a malignant phenotype in organotypic 'raft' culture, (2) showed in vitro anchorage-independency, (3) developed tumors in nude mice when injected subcutaneously, (4) contained a significantly higher copy number of intact and integrated HPV-16 DNA; (5) contained higher level of HPV-16 E6/E7 messages and E7 protein, (6) were more resistant to transforming growth factor-beta 1 and (7) secreted higher level of vascular endothelial growth factor with molecular weight of 56 kd than parental HOK-16B-BaP cells. However, the levels of p53 and ras proteins and the levels of p53, c-myc and c-fos transcripts in the HOK-16B-BaP-T cells were not different from those in the HOK-16B-BaP cells. The highly conserved coding regions of the p53, c-Ha-ras1, and c-Ki-ras2 genes of the tumor cells were not mutated. These data indicate that the HPV-immortalized human oral keratinocytes can convert to tumorigenic cells by chronic exposure to benzo(a)pyrene. The tumorigenic conversion seems to be associated with (1) the overexpression of viral oncogenes such as E6 and E7 genes, (2) the higher resistance of cells to transforming growth factor-beta 1 and (3) the high secretion of 56 kd vascular endothelial growth factor from the cells.

Activity of human papillomavirus type 16 P97 promoter in immortal and tumorigenic human oral keratinocytes.

We previously immortalized normal human oral keratinocytes (NHOK) by transfection with cloned human papillomavirus type 16 (HPV-16) genome and converted these immortalized cells to tumorigenic cells with chemical carcinogens. Since the tumorigenic cells expressed higher level of HPV-16 E6/E7 transcripts, we predicted that enhanced E6/E7 expression was induced by mutations at the long control region (LCR) of the viral genome integrated into cellular chromosome. To test this possibility, we sequenced the entire HPV-16 LCR from immortalized and tumorigenic cells, but no difference in the sequences in all of the tested cells was observed. However, it is possible that such differences in the expression of E6/E7 could have originated from different activities of cellular transcription factors in the different cells. To examine this prospect, we subcloned entire LCR into a reporter gene and determined the promoter activity of LCR in immortalized and tumorigenic cells. We found that the LCR promoter activity was significantly higher in tumorigenic cells when comparing to immortalized cells. We also observed that at least 477 nucleotides upstream of E6 open reading frame are needed for the maximum LCR promoter activity in tumorigenic cells.

Conversion of normal human oral keratinocytes to tumorigenic cells is associated with the acquisition of resistance to TGF-beta.

Normal human epithelial cells cannot proliferate and undergo apoptosis in the presence of transforming growth factor-beta (TGF-beta) in vitro, but many human epidermoid cancer cells are resistant to TGF-beta. Resistance to TGF-beta may thus, in part, be responsible for uncontrolled proliferation of cancer cells. Though detailed mechanisms for the resistance of cancer cells to TGF-beta remain unknown, resistance may be due to decreased expression of TGF-beta receptors from cancer cells. To investigate this possibility, we determined the expression of TGF-beta and type II TGF-beta receptor in primary normal human oral keratinocytes (NHOK), human papillomavirus-immortalized human oral keratinocytes (HOK-16B) and two tumor cell lines derived from HOK-16B (CTHOK-16B-BaP and CTHOK-16B-DMBA). Our results show that (1) the cellular and secretory TGF-beta levels in immortalized and tumor cells were notably lower than in NHOK and (2) the level of type II TGF-beta receptor of the tested cells was similar to each other. Taken together, the conversion of NHOK to tumorigenic cells may, in part, be due to the acquisition of NHOK resistance to TGF-beta through underexpression of this cytokine.

Comparison of inferior oblique muscle weakening by anterior transposition or myectomy: a prospective study of 20 cases.

BACKGROUND/AIMS: Among the various weakening techniques of inferior oblique muscle overaction, the most commonly used techniques include myectomy, recession, and anterior transposition. Anterior transposition and myectomy were compared to evaluate the surgical results in inferior oblique overaction. METHODS: 20 children with bilateral +3 overacting inferior oblique muscles underwent a prospective randomised study by which the anterior transposition procedure in one eye was compared with the myectomy procedure in the other eye. RESULTS: Postoperative follow up averaged 2 years. The success rates in two surgical procedures were 85% for the anterior transposition and 25% for the myectomy (standard of success was based on zero inferior oblique overaction). In only one case did the anterior transposition tend to limit the elevation of the eye in the midline, adduction, and abduction. Anterior transposition produced hypotropia at the primary position in only one case. Most eyes that underwent myectomy (75%) showed apparent residual overaction. CONCLUSION: The anterior transposition appeared to be more effective in eliminating the overaction of inferior oblique muscle than the myectomy.

Concurrence of replicative senescence and elevated expression of p16(INK4A) with subculture-induced but not calcium-induced differentiation in normal human oral keratinocytes.

Primary normal human oral keratinocytes (NHOKs) undergo differentiation in the presence of calcium concentrations higher than 0.15 mM in vitro, which is useful in investigating the mechanisms involved in the differentiation of epithelial cells. Serial subculture of NHOKs to the postmitotic stage also induces terminal differentiation. However, the detailed mechanisms of both differentiation processes remain substantially unknown. To investigate the molecular differences in these processes, NHOKs were induced to differentiate by exposure to 1.2 mM of calcium and by serial subculture to the postmitotic stage. To study whether the cells were induced to differentiate and to undergo replicative senescence, the amount of cellular involucrin and the expression of senescence-associated beta-galactosidase (SA-beta-gal) were measured respectively. The expression of replicative senescence-associated genes and the activity of telomerase from the differentiated cells were also determined. Both calcium treatment and serial subculture to the postmitotic stage notably elevated the cellular involucrin. The percentage of SA-beta-gal-positive cells was significantly elevated by the continued subculture, but such changes were not observed in keratinocytes exposed to calcium. The concentration of cellular p16(INK4A) protein was progressively increased by the continued subculture but was not changed by calcium treatment. On the other hand, the concentrations of cellular p53 were similar in both differentiation processes. However, telomerase activity was lost in NHOKs that had undergone differentiation by both calcium treatment and serial subculture. The results indicate that calcium-induced differentiation of NHOKs has similar characteristics to their serial subculture-induced differentiation, but that the differentiation processes are not identical, because calcium-induced differentiation does not concur with either replicative senescence or the gradually increased concentration of p16(INK4A).

Staphylococcus lugdunensis--a potential pathogen in oral infection.

OBJECTIVE: The purpose of this study was to investigate the pathogenicity of Staphylococcus lugdunensis in acute oral infection. STUDY DESIGN: S. lugdunensis was isolated from patients with acute oral infections and from healthy control subjects. Antibiotic susceptibility, in vitro cellular toxicity, in vivo virulence, and hemolytic activity testing and dot blot analysis were performed. The statistical significance of in vitro cellular toxicity was determined by means of analysis of variance. RESULTS: Isolated from the infected patients, S. lugdunensis showed resistance to penicillin, ampicillin, methicillin, cephalothin, and clindamycin, exhibited virulence in vivo, and showed delta-like hemolysin activity. Four of the 6 strains of S. lugdunensis gave synergistic hemolysis. In dot blot analysis, S. lugdunensis showed a positive reaction to the probe of the delta-hemolysin gene in S. aureus. CONCLUSIONS: The results suggest that S. lugdunensis may be a potential pathogen in acute oral infection.

A randomized comparison of prism adaptation and augmented surgery in the surgical management of esotropia associated with hypermetropia: one-year surgical outcomes.

OBJECTIVE: To compare motor and sensory 1-year surgical outcomes in patients with hypermetropic esotropia, managed with either augmented surgery based on the average of the near deviation with and without correction or preoperative prism adaptation. METHODS: Forty-three patients with hypermetropic esotropia without distance-near disparity entered a randomized prospective evaluation of augmented surgery (group A, 27 patients) versus prism adaptation (group P, 16 patients). The formula for augmenting the amount of the rectus muscle recession was based on the average of the near deviation with and without correction in group A and the prism-adapted angle of deviation in group P. During prism adaptation, 9 of 16 patients in group P responded to prism. Motor and sensory outcomes of the Worth 4-dot test at 6 and 0.33 m and the Titmus stereotest were evaluated 1, 3, 6, and 12 months after surgery. RESULTS: Postoperative deviations of 8 PD or less at distance were achieved in 24 of 27 patients (89%) of group A and in 7 of the remaining 8 patients (88%) of prism responders and in all 7 prism nonresponders (100%) in group P. No significant difference existed between groups A and P, as well as between the prism responders and prism nonresponders in group P in terms of near and distance deviation 1 year after surgery. The sensory outcomes improved over time in group A and prism responders. CONCLUSION: There were no significant differences in the surgical outcomes between each group. However, the small sample size may limit the power to detect any statistically significant differences.

Comparison of superior oblique tendon expander to superior oblique tenotomy for the management of superior oblique overaction and Brown syndrome.

We compared surgical results of superior oblique tenotomy to the superior oblique silicone expander for the treatment of superior oblique overaction and Brown syndrome. Of 24 patients with bilateral superior oblique overaction, 13 underwent tenotomy and 11 had the silicone expander procedure. Reduction of A-pattern to within 10 prism diopters was achieved in 12/13 (92.3%) tenotomy patients and in 10/11 (90.9%) patients undergoing silicone expander (P greater than .05). Correction of superior oblique overaction on versions to within +/- 1 dysfunction was achieved in 22/26 (84.6%) of the tenotomies, and 21/22 (95.5%) silicone expander procedures (P greater than .05). Zero superior oblique dysfunction was found after 14/26 (53.8%) tenotomy procedures versus 18/22 (81.8%) silicone expander operations (P = .041). Superior oblique paresis occurred postoperatively in 4/13 (30.8%) tenotomy patients, whereas none of the 11 patients in the silicone expander group had superior oblique paresis (P = .044). Six patients who underwent superior oblique tenotomy for superior oblique overaction had preoperative stereopsis; following surgery, only two maintained the same level of stereopsis, and three patients totally lost all stereo acuity. All patients in the silicone expander group either maintained or had improved stereo acuity postoperatively. Seven patients with true Brown syndrome were operated on: three underwent the silicone expander procedure and four had a superior oblique tenotomy with an ipsilateral inferior oblique recession. The combination of superior oblique tenotomy with simultaneous ipsilateral inferior oblique recession resulted in an undercorrection in two of the four patients, whereas all three patients in the silicone expander group showed excellent ocular motility postoperatively, with two having normal versions and one a -1 residual limitation.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized comparison of prism adaptation and augmented surgery in the surgical management of esotropia associated with hypermetropia.

OBJECTIVE: To compare both motor and sensory surgical outcomes for patients with esotropia associated with hypermetropia managed with an augmented surgery based on the average of the near deviation with and without correction vs preoperative prism adaptation. METHODS: Forty-three patients with esotropia associated with hypermetropia entered a randomized prospective evaluation of augmented surgery (group A, 27 patients) versus prism adaptation (group P, 16 patients). The formula for augmenting the amount of the rectus muscle recession was based on the average of the near deviation with and without correction in group A, and the prism-adapted angle of deviation in group P. RESULTS: In group A, postoperative deviations of 8 prism diopters (delta) or less at distance and at near were achieved in 24 patients (88%), and in 22 patients (81%), respectively. In nine prism responder patients, postoperative deviations of 8 delta or less at distance and at near were achieved in eight patients (89%). In seven nonresponder patients, postoperative deviations of 8 delta or less at distance and at near were achieved in six patients (86%). No significant difference between the two groups in terms of near and distance deviation at 1 and 3 months postoperatively were noted. CONCLUSION: No significant difference existed in the motor outcomes between the two groups, or between the prism responder and prism nonresponder groups. Further detailed studies must be made in a large number of patients.

A muscle-clamping system with an absorbable jaw clip to reduce suturing in strabismus surgery.

Most of the ocular complications of strabismus surgery are related to needle trauma during the suturing of muscles. The authors have developed a muscle-clamping system with an absorbable jaw clip to facilitate exact techniques of eye muscle surgery and to reduce the risk of complications. The absorbable jaw clip is composed of a lower fixing body with three jaws and an upper supporting body. The clip is used to tie an extraocular muscle (which is moved and reattached with the membrane) with a single scleral bite. Using the absorbable jaw clip, the authors performed superior rectus recession on 16 eyes of eight rabbits. The authors examined the conjunctival injection, muscle adhesion power, and light microscopic findings at 1, 2, 4, and 8 weeks postoperatively. The conjunctival injection diminished with time. Bond strengths ranged from 380 to 620 gram gravity, which is sufficient to withstand the normal pull of human extraocular muscles. Some inflammatory cells were found microscopically, and fibrosis increased with time. The muscle-clamping method with the newly invented clip was technically easy, fast, and exact, and it may reduce suturing and complications during strabismus surgery.

Effect of a modified rectus tuck on anterior ciliary artery perfusion.

Strabismus surgery results in the permanent interruption of anterior ciliary blood flow, predisposing the eye to anterior segment ischemia (ASI). A primate model was used to assess the effectiveness of a new muscle-scleral tuck for preserving anterior ciliary artery circulation. The model consisted of removing 3 rectus muscles from both eyes of 2 rhesus monkeys, then performing a tuck on the inferior rectus (IR) right eye while leaving the left IR as a control. Four weeks later, a modified tuck was performed on the virgin left IR. Fluorescein iris angiograms of both eyes were obtained, and preoperative angiograms at 5-15 sec. showed normal 360 degrees perfusion. Postoperative follow-up angiograms showed segmental superior temporal filling defects and preservation of perfusion in the distribution of the IR. Comparison of fellow eyes tucked vs control IR showed no difference in the filling pattern in both monkeys. Comparison of the same eye before and after tuck also showed essentially the same filling pattern in all 4 eyes with preservation of inferior circulation. Our conclusion is that the modified tuck preserves the anterior ciliary blood flow and may be useful as a muscle-strengthening procedure in patients predisposed to developing ASI.

A comparison of Min's glasses and conventional occlusion therapy in the treatment of amblyopic children: a prospective study.

Min's glasses are specially manufactured in order to enhance the satisfaction of the wearer and increase treatment effectiveness. We compared the effectiveness of Min's glasses with that of conventional occlusion therapy in amblyopic pediatric patients. We prospectively studied 60 amblyopic patients. For four to 30 months, 24 of the patients were treated with conventional patch occlusion (patch group) and 36 of them were treated with Min's glasses (glasses group). We compared the improvement in visual acuity and the treatment compliance between both groups, according to age (over six and less than six), sex, type of amblyopia, and the duration of treatment. Sixteen patients (66.7%) in the patch group and 32 patients (88.9%) in glasses group showed improvement in visual acuity (p = 0.002). The pre-treatment average log MAR acuity was 0.56 +/- 0.25 in the patch group, and 0.59 +/- 0.25 in the glasses group. The average improvement in visual acuity was a 0.17 log MAR score in the patch group, and a 0.31 log MAR score in the glasses group (p = 0.004). Compliance was 59.54% in the patch group and 83.44% in the glasses group (p = 0.012). The pre-treatment average log MAR acuity was 0.49 +/- 0.23 for children over six years of age in the patch group, and 0.58 +/- 0.28 for children over six years of age in the glasses group. For children over six years of age in the glasses group the improvement in visual acuity (0.29 log MAR score) was greater than for children over six years of age in the patch group (0.06 log MAR score) (p = 0.0003). The pre-treatment average log MAR acuity was 0.55 +/- 0.22 for female patients in the patch group, and 0.60 +/- 0.25 for female patients in the glasses group. Female patients in the glasses group also showed a greater visual acuity improvement (0.29 log MAR score) than female patients in the patch group (0.14 log MAR score) (p = 0.0028). However, there were no differences between the groups in patients less than six years of age and in male patients. In conclusion, Min's glasses were more effective than conventional treatment with a patch in improving visual acuity and encouraging compliance in pediatric amblyopic patients, especially in children over six years of age and in girls.

A laminin-2-derived peptide promotes early-stage peripheral nerve regeneration in a dual-component artificial nerve graft.

The DLTIDDSYWYRI motif (Ln2-P3) of human laminin-2 has been reported to promote PC12 cell attachment through syndecan-1; however, the in vivo effects of Ln2-P3 have not been studied. In Schwann cells differentiated from skin-derived precursors, the peptide was effective in promoting cell attachment and spreading in vitro. To examine the effects of Ln2-P3 in peripheral nerve regeneration in vivo, we developed a dual-component poly(p-dioxanone) (PPD)/poly(lactic-co-glycolic acid) (PLGA) artificial nerve graft. The novel graft was coated with scrambled peptide or Ln2-P3 and used to bridge a 10 mm defect in rat sciatic nerves. The dual-component nerve grafts provided tensile strength comparable to that of a real rat nerve trunk. The Ln2-P3-treated grafts promoted early-stage peripheral nerve regeneration by enhancing the nerve regeneration rate and significantly increased the myelinated fibre density compared with scrambled peptide-treated controls. These findings indicate that Ln2-P3, combined with tissue-engineering scaffolds, has potential biomedical applications in peripheral nerve injury repair.

In-vivo-induced antigenic determinants of Fusobacterium nucleatum subsp. nucleatum.

Fusobacterium nucleatum plays a pivotal role in dental plaque biofilm formation and is known to be involved in chronic inflammatory systemic disease. However, limited knowledge of F. nucleatum genes expressed in vivo interferes with our understanding of pathogenesis. In this study, we identified F. nucleatum genes induced in vivo using in-vivo-induced antigen technology (IVIAT). Among 30,000 recombinant clones screened, 87 reacted reproducibly with pooled sera from 10 patients with periodontitis. The clones encoded for 32 different proteins, of which 28 could be assigned to their functions, which were categorized in translation, transcription, transport, energy metabolism, cell envelope, cellular process, fatty acid and phospholipid metabolism, transposition, cofactor biosynthesis, amino acid biosynthesis, and DNA replication. Putative virulence factors detected were ABC transporter, butyrate-acetoacetate CoA-transferase, hemin receptor, hemolysin, hemolysin-related protein, LysR family transcriptional regulator, serine protease, and transposase. Analysis of immune responses to the in-vivo-induced (ivi) antigens in five patients demonstrated that most were reactive to these proteins, confirming results with pooled sera. IVIAT-identified F. nucleatum genes in this study may accelerate the elucidation of F. nucleatum-mediated molecular pathogenesis.

Innate immune responses of gingival epithelial cells to nonperiodontopathic and periodontopathic bacteria.

BACKGROUND AND OBJECTIVE: We have previously reported different susceptibilities of periodontopathic and nonperiodontopathic bacteria to antimicrobial peptides and phagocytosis by neutrophils. Differences between the two groups of bacteria may exist also in their ability to induce immune responses from the host. Therefore, we evaluated the effects of various oral bacteria on innate immune responses by gingival epithelial cells. MATERIAL AND METHODS: HOK-16B cells were cocultured with live or lysed nonperiodontopathic (n = 3) and periodontopathic (n = 5) bacterial species. The levels of human beta defensin-1, -2 and -3, and of the cathelicidin, LL-37, were examined by real-time reverse transcription-polymerase chain reaction, and the accumulated interleukin-8 and interleukin-1 alpha were measured by enzyme-linked immunosorbent assay. RESULTS: Nonperiodontopathic bacteria up-regulated some antimicrobial peptides without affecting the levels of cytokines. In the periodontopathic group, the orange-complex bacteria induced antimicrobial peptides and interleukin-8 efficiently, but the red-complex bacteria often demonstrated suppressive effects. In contrast to live bacteria, bacterial lysates had no suppressive effects. In addition, some bacterial lysates demonstrated a reduced ability to induce antimicrobial peptides compared with live bacteria. CONCLUSION: The nonperiodontopathic, the orange-complex, and the red-complex bacteria had different effects on the innate immune responses from gingival epithelial cells, which may affect the outcome of their host-microbial interaction in gingival sulcus.