Caffeic Acid Phenethyl Ester Induces Vascular Endothelial Growth Factor Production and Inhibits CXCL10 Production in Human Dental Pulp Cells.

The survival rate of root non-vital teeth is lower than that of vital teeth. Therefore, to preserve the dental pulp is very important. The vascular endothelial growth factor (VEGF) is the most potent angiogenic factor involved in the vitality of dental pulp including reparative dentin formation. Caffeic acid phenethyl ester (CAPE) is a physiologically active substance of propolis and has some bioactivities such as anti-inflammatory effects. However, there are no reports on the effects of CAPE on dental pulp inflammation. In this study, we investigated the effects of CAPE on VEGF and inflammatory cytokine production in human dental pulp cells (HDPCs) to apply CAPE to an ideal dental pulp protective agent. We found that CAPE induced VEGF production from HDPCs. Moreover, CAPE induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinases (ERK), and stress-activated protein kinase/c-Jun N-terminal kinase (SAP/JNK) in HDPCs. Furthermore, CAPE inhibited C-X-C motif chemokine ligand 10 (CXCL10) production in Pam3CSK4- and tumor necrosis factor-alpha (TNF-α)-stimulated HDPCs. In conclusion, these results suggest that CAPE might be useful as a novel biological material for vital pulp therapy by exerting the effects of VEGF production and anti-inflammatory activities.

Phase II study of tazemetostat for relapsed or refractory B-cell non-Hodgkin lymphoma with EZH2 mutation in Japan.

Tazemetostat is a selective, reversible, small-molecule inhibitor of the histone methyltransferase enzyme, enhancer of zest homolog 2 (EZH2). In this multicenter, open-label, phase II study, we assessed the efficacy and safety of tazemetostat in Japanese patients with relapsed or refractory (R/R) B-cell non-Hodgkin lymphoma harboring the EZH2 mutation. Tazemetostat (800 mg twice daily) was given orally (28-day cycle) until disease progression or unacceptable toxicity. Among the 20 eligible patients, 17 were enrolled in cohort 1 (follicular lymphoma [FL]), and three were enrolled in cohort 2 (diffuse large B-cell lymphoma). At data cut-off, the objective response rate in cohort 1 was 76.5%, including six patients (35.3%) with complete response and seven patients (41.2%) with partial response (PR). All three patients in cohort 2 achieved PR. In cohort 1, median progression-free survival (PFS) was not reached at the median follow-up of 12.9 months. The estimated PFS rate at 12 and 15 months was 94.1% and 73.2%, respectively. The most common grade 3 treatment-emergent adverse event (TEAE) was lymphopenia (n = 2). Grade 4 TEAEs included hypertriglyceridemia and pneumonia aspiration (n = 1 each), which were not related to tazemetostat. Treatment-emergent adverse events leading to study drug discontinuation were reported in four of the 20 patients, indicating that the safety profile of tazemetostat was acceptable and manageable. Tazemetostat 800 mg twice daily showed encouraging efficacy in patients with R/R EZH2 mutation-positive FL with a manageable safety profile in the overall population. Thus, tazemetostat could be a potential treatment for R/R EZH2 mutation-positive FL.

Phase 1 study of tazemetostat in Japanese patients with relapsed or refractory B-cell lymphoma.

BACKGROUND: Tazemetostat is a selective and orally available inhibitor of enhancer of zeste homolog 2 (EZH2), a histone methyltransferase and epigenetic regulator of cellular differentiation programs. We carried out a phase I study of tazemetostat in Japanese patients with relapsed or refractory B-cell non-Hodgkin-type lymphoma (B-NHL) to evaluate its tolerability, safety, pharmacokinetics, and preliminary antitumor activity. METHODS: Tazemetostat was given orally at a single dose of 800 mg on the first day and 800 mg twice daily (BID: total 1600 mg/d) on following days in a 28-day/cycle manner. Tazemetostat dose-limiting toxicity (DLT) was evaluated up to the end of the first treatment cycle. Archival tumor tissues were analyzed for hotspot EZH2 mutations. RESULTS: As of 15 January 2018, seven patients (four follicular lymphoma [FL] and three diffuse large B-cell lymphoma [DLBCL]) were enrolled. The median age was 73 (range, 59-85) years, and the median number of prior chemotherapy regimens was three (range, one to five). No DLT was observed (one patient was not evaluable due to early disease progression). The common treatment-related adverse events (AEs) were thrombocytopenia and dysgeusia (three patients each; 42.9%). No treatment-related serious AEs were observed. The objective response rate was 57% (4/7 patients), including responses in three of four patients with FL and one of three patients with DLBCL. An EZH2 mutation was detected in one patient with FL responding to treatment. CONCLUSIONS: Tazemetostat at 800 mg BID showed an acceptable safety profile and promising antitumor activity in Japanese patients with relapsed or refractory B-NHL.

Phase II study of E7777 in Japanese patients with relapsed/refractory peripheral and cutaneous T-cell lymphoma.

E7777 is a recombinant cytotoxic fusion protein composed of the diphtheria toxin fragments A and B and human interleukin-2. It shares an amino acid sequence with denileukin diftitox, but has improved purity and an increased percentage of active monomer. We undertook a multicenter, single-arm phase II study of E7777 in patients with relapsed or refractory peripheral T-cell lymphoma (PTCL) and cutaneous T-cell lymphoma (CTCL) to evaluate its efficacy, safety, pharmacokinetics, and immunogenicity. A total of 37 patients were enrolled, of which 17 and 19 patients had PTCL and CTCL, respectively, and one patient with another type of lymphoma (extranodal natural killer/T-cell lymphoma, nasal type), diagnosed by the Central Pathological Diagnosis Committee. Among the 36 patients with PTCL and CTCL, objective response rate based on the independent review was 36% (41% and 31%, respectively). The median progression-free survival was 3.1 months (2.1 months in PTCL and 4.2 months in CTCL). The common adverse events (AEs) observed were increased aspartate aminotransferase (AST) / alanine aminotransferase (ALT), hypoalbuminemia, lymphopenia, and pyrexia. Our results indicated that a 9 µg/kg/d dose of E7777 shows efficacy and a manageable safety profile in Japanese patients with relapsed or refractory PTCL and CTCL, with clinical activity observed across the range of CD25 expression. The common AEs were manageable, but increase in ALT / AST, hypoalbuminemia, and capillary leak syndrome should be carefully managed during the treatment.

E7777 in Japanese patients with relapsed/refractory peripheral and cutaneous T-cell lymphoma: A phase I study.

E7777, a recombinant cytotoxic fusion protein comprising diphtheria toxin fragments A and B and human interleukin-2, shares an amino acid sequence with denileukin diftitox but has improved purity and an increased percentage of active protein monomer species. A phase I study was carried out to evaluate the tolerability, safety, pharmacokinetics, and antitumor activity of E7777 in Japanese patients with relapsed/refractory peripheral and cutaneous T-cell lymphoma. E7777 (6, 12, and expanded 9 µg/kg/day) was given to 13 patients by i.v. infusion on five consecutive days per 21-day cycle. Dose-limiting toxicities, including increased alanine aminotransferase, hyponatremia (n = 2), hypokalemia, lymphopenia, fatigue, hypoalbuminemia, rash, and increased lipase (n = 1), were observed in all three patients in the 12 µg/kg/day cohort, whereas two of six patients in the 9 µg/kg/day cohort showed decreased appetite or fatigue. The maximum tolerated and recommended dose of E7777 was 9 µg/kg/day for five consecutive days per 21-day cycle. The objective response rate was 38% (5/13) and did not appear to depend on tumor expression of CD25. E7777 was well tolerated, assuming careful management of adverse events during treatment, and preliminary but clinically meaningful antitumor activity was observed. Subsequent studies of E7777 for T-cell lymphomas are warranted. This study was registered with www.ClinicalTrials.gov (NCT1401530).

Phase 1 combination study of eribulin mesylate with trastuzumab for advanced or recurrent human epidermal growth factor receptor 2 positive breast cancer.

Eribulin mesylate (Halaven®) is a novel inhibitor of microtubule dynamics that has demonstrated a survival benefit in patients with locally recurrent or metastatic breast cancer who previously received at least two chemotherapeutic regimens including an anthracycline and a taxane. Although trastuzumab is indicated for patients with human epidermal growth factor receptor 2 positive (HER2+) breast cancer, a phase 1 study to evaluate tolerability/safety of eribulin mesylate with trastuzumab has not been conducted. Therefore, a study of eribulin mesylate in combination with trastuzumab was conducted to evaluate dose limiting toxicity (DLT), tolerability/safety, pharmacokinetics (PK), and efficacy and to estimate the recommended dose in Japanese patients with advanced or recurrent HER2+ breast cancer. Eribulin mesylate (1.4 mg/m(2)) was administered on days 1 and 8 of every 3 week cycle. Trastuzumab was administered with a 4 mg/kg loading dose followed by 2 mg/kg weekly doses or with an 8 mg/kg loading dose followed by 6 mg/kg tri-weekly doses. A total of 12 patients (six for each regimen) received eribulin mesylate and trastuzumab. No DLT was observed and the recommended dose of eribulin mesylate in combination with trastuzumab was estimated as 1.4 mg/m(2). Common adverse events were neutropenia, leukopenia, anaemia and alopecia. This combination therapy was well tolerated and the neutropenia observed was manageable. No PK drug-drug interaction between eribulin and trastuzumab was observed. Since a transient ejection fraction decreased was observed in two patients, cardiac function should be routinely assessed in patients receiving the combination therapy of eribulin mesylate with trastuzumab (ClinicalTrials.gov Identifier: NCT01432886).

Inhibition of matrix metalloproteinase-9 activity by doxycycline ameliorates RANK ligand-induced osteoclast differentiation in vitro and in vivo.

Tetracycline antibiotics, including doxycycli\e (DOX), have been used to treat bone resorptive diseases, partially because of their activity to suppress osteoclastogenesis induced by receptor activator of nuclear factor kappa B ligand (RANKL). However, their precise inhibitory mechanism remains unclear. Therefore, the present study examined the effect of Dox on osteoclastogenesis signaling induced by RANKL, both in vitro and in vivo. Although Dox inhibited RANKL-induced osteoclastogenesis and down-modulated the mRNA expression of functional osteoclast markers, including tartrate-resistant acid phosphatase (TRAP) and cathepsin K, Dox neither affected RANKL-induced MAPKs phosphorylation nor NFATc1 gene expression in RAW264.7 murine monocytic cells. Gelatin zymography and Western blot analyses showed that Dox down-regulated the enzyme activity of RANKL-induced MMP-9, but without affecting its protein expression. Furthermore, MMP-9 enzyme inhibitor also attenuated both RANKL-induced osteoclastogenesis and up-regulation of TRAP and cathepsin K mRNA expression, indicating that MMP-9 enzyme action is engaged in the promotion of RANKL-induced osteoclastogenesis. Finally, Dox treatment abrogated RANKL-induced osteoclastogenesis and TRAP activity in mouse calvaria along with the suppression of MMP9 enzyme activity, again without affecting the expression of MMP9 protein. These findings suggested that Dox inhibits RANKL-induced osteoclastogenesis by its inhibitory effect on MMP-9 enzyme activity independent of the MAPK-NFATc1 signaling cascade.

Comparative studies of lepidopteran baculovirus-specific protein FP25K: development of a novel Bombyx mori nucleopolyhedrovirus-based vector with a modified fp25K gene.

Lepidopteran baculovirus-specific protein FP25K performs many roles during the infection cycle, including functions in the production of occlusion bodies (OBs) and budded viruses (BVs), oral infection, and postmortem host degradation. To explore the common and specific functions of FP25K proteins among lepidopteran baculoviruses, we performed comparative analyses of FP25K proteins from group I and group II nucleopolyhedroviruses (NPVs) and granulovirus (GV). Using recombinant Bombyx mori NPVs (BmNPVs), we showed that the FP25Ks from NPVs were able to eliminate all the phenotypic defects observed in an infection with a BmNPV mutant lacking functional fp25K but that FP25K from GV did not show abilities to recover oral infectivity and postmortem host degradation. We also observed that introduction of Autographa californica multiple NPV (AcMNPV) fp25K into the BmNPV genome enhanced OB and BV production. According to these results, we generated a novel BmNPV-based expression vector with AcMNPV fp25K and examined its potential in BmN cells and B. mori larvae. Our results showed that the introduction of AcMNPV fp25K significantly increases the expression of foreign gene products in cultured cells and shortens the time for obtaining the secreted recombinant proteins from larval hemolymph.

Characterization of a Bombyx mori nucleopolyhedrovirus mutant lacking both fp25K and p35.

Recent studies have shown that dual mutations in fp25K and p35 of Autographa californica nucleopolyhedrovirus (AcMNPV) result in a typical apoptotic infection on Trichoplusia ni cells, suggesting the involvement of FP25K on NPV-induced apoptosis. To examine the effect of fp25K deletion on Bombyx mori NPV (BmNPV)-induced apoptosis, we generated a BmNPV mutant, fp-p35D, in which both fp25K and p35 genes are deleted from the genome, and compared its phenotype with wild-type (T3), fp25K-deleted (fp-null), and p35-deleted (p35D) BmNPVs. In BmN cells, p35D, but not T3 or fp-null, caused apoptosis with caspase-3 activation. Infection with fp-p35D also resulted in caspase-3 activation, but the level was comparable to that of p35D. Also, we did not observe any apoptotic responses in hemocytes from larvae infected with p35D or fp-p35D. These results indicate that unlike AcMNPV, deletion of fp25K does not affect the pathway of p35D-induced apoptosis of BmN cells and B. mori larvae.

Anti-inflammatory effect of catechin on cultured human dental pulp cells affected by bacteria-derived factors.

Catechins (bioactive polyphenols in green tea) are known to exhibit potent anti-inflammatory properties. However, the anti-inflammatory effects of catechins on inflamed dental pulp tissue are not known. In this study, we investigated the effect of epigallocatechin-3-gallate (EGCG) and epicatechin gallate (ECG), the major components of green tea catechins, on the expression of pro-inflammatory cytokines and adhesion molecules in human dental pulp cells stimulated with bacteria-derived factors such as lipopolysaccharide (LPS) and peptidoglycan (PG). The expression of interleukin (IL)-6 and of IL-8 was examined using the reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assays. The expression of intercellular adhesion molecule-1 (ICAM-1) and of vascular cell adhesion molecule-1 (VCAM-1) on dental pulp cells was analyzed using flow cytometry. The presence of EGCG and ECG significantly reduced, in a concentration-dependent manner, the expression of IL-6 and IL-8 in dental pulp cells exposed to LPS or PG. Increased expression of ICAM-1 and VCAM-1 on the dental pulp cells in response to bacterial components was also decreased by treatment with EGCG and ECG. These findings suggest that green tea catechins may prevent the exacerbation of pulpitis.

Catechins inhibit CCL20 production in IL-17A-stimulated human gingival fibroblasts.

CC chemokine ligand 20 (CCL20) plays a pivotal role in the recruitment of Th17 cells and thus in the development of periodontal disease. Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), the major catechins in green tea, have multiple beneficial effects, but the effects of catechins on CCL20 production in human gingival fibroblasts (HGFs) are not known. In this study, we investigated the mechanisms by which EGCG and ECG inhibit interleukin (IL)-17A-induced CCL20 production in human gingival fibroblasts. IL-17A increased CCL20 production in HGFs in a concentration-dependent manner. EGCG and ECG prevented IL-17A-mediated CCL20 production in HGFs. Inhibitors of p38 mitogen-activated protein kinase (MAPK) or extracellular signal-regulated kinase (ERK) decreased IL-17A-induced CCL20 production. EGCG and ECG prevented IL-17A-induced phosphorylation of p38 MAPK and ERK in HGFs. In addition, EGCG and ECG attenuated IL-17 receptor expression on HGFs. These data provide a novel mechanism through which the green tea flavonoids catechins could be used to provide direct benefits in periodontal disease.

Bombyx mori nucleopolyhedrovirus FP25K is essential for maintaining a steady-state level of v-cath expression throughout the infection.

It has been previously reported that the fp25K product of Bombyx mori nucleopolyhedrovirus (BmNPV) is required for post-mortem host degradation, but the mechanism by which it regulates host degradation is still unknown. This study shows that disruption of BmNPV fp25K attenuates the expression of viral cathepsin gene (v-cath) at a late stage of infection, and thus reduces the secretion of its product V-CATH. Western blot analysis showed that secretion of V-CATH was severely reduced in BmN cells and B. mori larvae infected with Bm25KD, a BmNPV mutant lacking functional fp25K, compared to that of wild-type BmNPV. Also, reduced accumulation of pro-V-CATH in Bm25KD-infected cells was observed from 4 days postinfection (dpi), during which V-CATH was first detected in the medium of BmNPV-infected cells. qRT-PCR experiments showed that the expression levels of v-cath mRNA in wild-type- and Bm25KD-infected BmN cells were comparable at 3 dpi, but showed a marked decrease in Bm25KD-infected BmN cells at 4 dpi. Collectively, these results suggest that BmNPV FP25K is essential for the proper transcriptional regulation of v-cath and efficient secretion of V-CATH, and a steady-state level of v-cath expression during the period of V-CATH secretion (after 4 dpi) is required for post-mortem host degradation.

Caffeic Acid Phenethyl Ester (CAPE) Induces VEGF Expression and Production in Rat Odontoblastic Cells.

Caffeic acid phenethyl ester (CAPE), the main component of propolis, has various biological activities including anti-inflammatory effect and wound healing promotion. Odontoblasts located in the outermost layer of dental pulp play crucial roles such as production of growth factors and formation of hard tissue termed reparative dentin in host defense against dental caries. In this study, we investigated the effects of CAPE on the upregulation of vascular endothelial growth factor (VEGF) and calcification activities of odontoblasts, leading to development of novel therapy for dental pulp inflammation caused by dental caries. CAPE significantly induced mRNA expression and production of VEGF in rat clonal odontoblast-like KN-3 cells cultured in normal medium or osteogenic induction medium. CAPE treatment enhanced nuclear factor-kappa B (NF-κB) transcription factor activation, and furthermore, the specific inhibitor of NF-κB significantly reduced VEGF production. The expression of VEGF receptor- (VEGFR-) 2, not VEGFR-1, was up regulated in KN-3 cells treated with CAPE. In addition, VEGF significantly increased mineralization activity in KN-3 cells. These findings suggest that CAPE might be useful as a novel biological material for the dental pulp conservative therapy.

Computed tomographic air-contrast enema imaging for presurgical examination of colon tumors: assessment with colon phantoms and in patients.

PURPOSE: We investigated the mechanism of colon wall deformities in phantoms and assessed the relation between pathological T staging and wall deformity in patients using computed tomography (CT) enema imaging. MATERIALS AND METHODS: We performed multidetector-row CT in mass-containing phantoms with no structural deformities and in 36 patients with colon tumors. In the phantoms, we compared images on double-contrast barium (DCB) and CT enema studies, and we compared wall deformities on CT enema studies and the actual phantom structure. In patients, we compared wall deformities on CT enema studies and T staging. RESULTS: Images from CT enema and DCB studies were identical in the phantom, and all profile images showed geometrical basal indentations. In patients, the grade of deformity increased with invasion depth; and the diagnostic accuracy of T staging was 82.5%. Geometrical basal indentation and poor colon expansion were the primary reasons for overestimating T staging on CT enema imaging. CONCLUSION: Although CT enema imaging allows reasonable diagnostic accuracy of T staging, wall deformity is thought to be consistent with tumor infiltration and other factors. We recommend evaluating T staging using not only CT enema imaging but also other techniques, such as virtual endoscopy, axial imaging, and multiplanar reformation imaging.

The roles of odontoblasts in dental pulp innate immunity.

Odontoblasts located in the outermost layer of dental pulp form a natural barrier between mineralized tissues, dentin, and soft tissues, dental pulp, of the vital tooth, and they first recognize caries-related pathogens and sense external irritations. Therefore, odontoblasts possess a specialized innate immune system to fight oral pathogens invading into dentin. Generally, the rapid initial sensing of microbial pathogens, especially pathogen-associated molecular patterns (PAMPs) shared by microorganisms, are mediated by pattern recognition receptors (PRRs), such as Toll-like receptor and the nucleotide-binding oligomerization domain (NOD). The innate immune responses in odontoblasts initiated by sensing oral pathogens provide host protective events, such as inflammatory reactions, to produce a variety of pro-inflammatory mediators, including chemokines and cytokines. These attract various inflammatory cells and cause antibacterial reactions, such as the production of defensins, to kill microorganisms in the proximal region of the odontoblast layer. This review focuses on innate immunity, especially cellular and molecular mechanisms regarding the sensing of PAMPs from oral pathogens by PRRs, in odontoblasts and provides information for future studies for the development of novel therapeutic strategies, including diagnosis and treatment, to prevent exceeding dental pulp inflammation and preserve the dental pulp tissues.

MR imaging features of solid-pseudopapillary tumor of the pancreas.

Solid-pseudopapillary tumor (SPT) of the pancreas is characterized as cystic, necrotic, and hemorrhagic degeneration. In this study, magnetic resonance (MR) findings of 4 cases were reviewed. Patchy or spotty areas of high intensity that suggested hemorrhagic degeneration were constantly detected on fat-suppressed T(1)-weighted images. Dynamic contrast-enhanced MR imaging revealed mild and gradual increase of contrast enhancement in solid portions. Multi-contrast MR imaging that included fat-suppressed T(1)-weighted imaging and dynamic contrast-enhanced imaging allowed accurate diagnosis of SPT and its differentiation from other tumors.

Functional Roles of NOD1 in Odontoblasts on Dental Pulp Innate Immunity.

Caries-related pathogens are first recognized by odontoblasts and induce inflammatory events that develop to pulpitis. Generally, initial sensing of microbial pathogens is mediated by pattern recognition receptors, such as Toll-like receptor and nucleotide-binding oligomerization domain (NOD); however, little is known about NODs in odontoblasts. In this study, the levels of NODs expressed in rat odontoblastic cell line, KN-3, were assessed by flow cytometry and the levels of chemokines in NOD-specific ligand-stimulated KN-3 cells were analyzed by real-time PCR and ELISA. The signal transduction pathway activated with NOD-specific ligand was assessed by blocking assay with specific inhibitors and reporter assay. In KN-3 cells, the expression level of NOD1 was stronger than that of NOD2 and the production of chemokines, such as CINC-1, CINC-2, CCL20, and MCP-1, was upregulated by stimulation with NOD1-specific ligand, but not with NOD2-specific ligand. CINC-2 and CCL20 production by stimulation with NOD1-specific ligand was reduced by p38 MAPK and AP-1 signaling inhibitors. Furthermore, the reporter assay demonstrated AP-1 activation in NOD1-specific ligand-stimulated KN-3 cells. These findings indicated that NOD1 expressed in odontoblasts functions to upregulate the chemokines expression via p38-AP-1 signaling pathway and suggested that NOD1 may play important roles in the initiation and progression of pulpitis.

Pitfalls in 16-detector row CT of the coronary arteries.

Recently developed 16-detector row computed tomography (CT) has been introduced as a reliable noninvasive imaging modality for evaluating the coronary arteries. In most cases, with appropriate premedication that includes beta-blockers and nitroglycerin, ideal data sets can be acquired from which to obtain excellent-quality coronary CT angiograms, most often with multiplanar reformation, thin-slab maximum intensity projection, and volume rendering. However, various artifacts associated with data creation and reformation, postprocessing methods, and image interpretation can hamper accurate diagnosis. These artifacts can be related to pulsation (nonassessable segments, pseudostenosis) as well as rhythm disorders, respiratory issues, partial volume averaging effect, high-attenuation entities, inappropriate scan pitch, contrast material enhancement, and patient body habitus. Some artifacts have already been resolved with technical advances, whereas others represent partially inherent limitations of coronary CT angiography. Familiarity with the pitfalls of coronary angiography with 16-detector row CT, coupled with the knowledge of both the normal anatomy and anatomic variants of the coronary arteries, can almost always help radiologists avoid interpretive errors in the diagnosis of coronary artery stenosis.

Expression of macrophage inflammatory protein 3alpha in human inflamed dental pulp tissue.

Severe pulpitis resulting from dental caries is characterized by marked inflammatory infiltrate such as lymphocytes. Little is known about the recruitment of these cells into the dental pulp lesions of carious teeth. Macrophage inflammatory protein-3alpha (MIP-3alpha), a CC chemokine attracts CC chemokine receptor 6 (CCR6)-expressing T cells. We examined the distribution of MIP-3alpha-positive and/or CCR6-positive cells in human inflamed and normal dental pulp by immunohistochemistry. MIP-3alpha was observed in all inflamed pulp sections, and was mostly distributed in macrophages that had accumulated in the area adjacent to carious lesions. Furthermore, CCR6 expression was also observed in the infiltrating lymphocytes. In contrast, MIP-3alpha and CCR6 were rarely detected in normal pulp. These findings suggest that MIP-3alpha plays a role in the advancement of pulpal inflammation via the recruitment of CCR6-expressing lymphocytes.

An immunohistological study of the localization of bacteria invading root pulpal walls of teeth with periapical lesions.

We immunohistologically examined the prevalence and localization of bacteria invading dentinal tubules of the roots of teeth with infected canals. Forty extracted teeth with apical lesions were selected and divided into two groups: a group of untreated teeth and a group of canal-enlarged teeth. The bacteria in the specimens were detected by Brown-Brenn stain and the labeled-streptavidin-biotin method with specific antisera for 16-bacteria. Seventy percent of the examined teeth showed bacteria invading the dentinal tubules of the roots. Fusobacterium nucleatum, Eubacterium alactolyticum, E. nodatum, Lactobacillus casei, and Peptostreptococcus micros were abundant. Even in the canal-enlarged group, invasion of bacteria was observed in 65% of teeth. This study revealed the actual condition of bacteria in infected root dentin and suggested that the canal-enlargement procedure could not completely remove all the bacteria in the infected dentinal tubules of the root.