Kyudai Oral Bioscience&
OBT Research Center
6th Joint International Symposium 2022
PROGRAM & ABSTRACTS

October 29-30, 2022
Zoom Webinar/Lecture Room AB,
Faculty of Dental Science,
Kyushu University

K

OB

2022

■ Date:October 29-30, 2022
■ Hybrid: Zoom Webinar/Lecture room AB■ Organization
Kyudai Oral Bioscience
Oral Health・Brain Health・Total Health Research Center■ Contact
Eijiro Jimi
Oral Health・Brain Health・Total Health Research Center
Laboratory of Molecular and Cellular Biochemistry,
Faculty of Dental Science, Kyushu University,
Fukuoka 812-8582, Japan
Tel & Fax: +81 92-642-6332
E-mail: ejimi@dent.kyushu-u.ac.jp

6th KOB & OBT Joint International Symposium 2022

PROGRAMDAY 1Time

October 29 (Saturday)

Title

Presenter

10:20–10:30 Opening Remark

Prof. Seiji Nakamura

Session 1

Chair:
Hu ChenTsukasa Aoki

Graduate Student's Session

10:30–10:45 ﻿Wnt signaling promotes tooth germ development mediated by YAP1-TGF-β signaling

Ryoko Nagano

10:45–11:00 Effect of carbonate apatite as a bone substitute from the perspective of mesenchymal stem cells

Ryosuke Takahashi

11:00–11:15 A role of SCN1A in stem cells from human exfoliated deciduous teeth

MHD Fouad Zakaria

11:15–11:30 ﻿Long-term administration of bisphosphonates enhances aversive behavioral responses to HCl

Asami Oike

11:30–11:45 Involvement of TNF-α produced by TLR8+ monocytes/macrophages in the initiation of Sjögren’s syndrome

Yuka Miyahara

Extrafollicular B cell response in two different disease milieus: IgG4-relate disease and oral squamous cell
11:45–12:00
carcinoma

Hu Chen

12:00–13:00 Lunch Break
Chair:
Dr. Zhou Wu

Session 2

OBT Special Lecture (1)13:00–14:00

Targeting hypothalamus-habenula synapses – a novel circuitry mechanism for prevention strategy of chronic stress Dr. Yihui Cui
School of medicine,induced depression

Zhejiang University, China

14:00–14:15 BreakSession 3

JICA Session

Chair:
Dr. Tomoyo Yasukochi
Dr. Minoru Nakata,

14:15–14:45 Some memorandums about International Activities of Kyushu University Faculty of Dentistry

14:45–15:45

FLOW OF LIFE WITH AND WITHOUT KYUSHU UNIVERSITY
Comparison Of The Effect Of Proanthocyanidin Surface Treatments On Shear Bond Strength Of Different Cements

Professor Emeritus,
Kyushu University

Prof. Dr. A. Nehir Özden
Eastern Mediterranean University,
Cyprus

15:45–16:00 BreakSession 4

OBT Special Lecture (2)16:00–16:45

Osteoblast Lineage-Specific Cell-Surface Antigen Regulating Osteoclastogenesis and Calcification: A Possible
New Player in Bone Remodeling

Chair:
Prof. Eijiro Jimi
Dr. Tamer Badawy
Cairo University, Egypt
Galala University, Egypt

16:45–17:00 BreakSession 5

KOB Session

17:00–17:20 ﻿Artifical Intelligence and Blockchain in Dentistry and Radiology: What does the future hold?
17:20–17:40

Prevalence and predictors of bruxism patients with dental implants: a symptom-based diagnosis and prevention
strategy

Chair:
Prof. Eijiro Jimi
Prof. Dr. Kaan Orhan
Ankara University, Turkey

Prof. Dr. Volkan Arısan
Istanbul University, Turkey

In Vitro immunomodulation of Human Periodontal Ligament Stem Cells on Dendritic Cells Phenotype and Function
17:40–18:00 in Type 1 Diabetes
The Association between Anti-Asthma Medications and Periodontal HealthProf. Dr. Rola Alhabashneh

DAY 1

October 30 (Sunday)

Jordan University of Science andTechnology (JUST) , Jordan

Time

Title

Presenter

9:00–9:15

Award Presentation

Prof. Seiji Nakamura

Session 6

Award lectures

Chair:
Prof. Hidefumi Maeda
Prof. Tamotsu Kiyoshima

9:15–9:35

RAF1–MEK/ERK pathway-dependent ARL4C expression promotes ameloblastoma cell proliferation and osteoclast
Dr. Shinsuke Fujii
formation

9:35–9:55

Regeneration of glomerular metabolism and function by podocyte pyruvate kinase M2 in diabetic nephropathy

Dr. Takanori Shinjo

9:55–10:15

Targeted inhibition of EPAS1–driven IL-31 production by a small-molecule compoundDr. Yasuhisa Kamikaseda

10:15–10:35 CD163+ M2 macrophages promote fibrosis in IgG4-related disease via TLR7/IRAK4/NF-κB signaling.

Dr. Akira Chinju

10:35–10:50 BreakSession 7

DDR Session

10:10-10:20 Regulation of tooth development by Epiprofin

Chair:
Prof. Takayoshi Yamaza
Dr. Takashi Nakamura
Tohoku University

Prof. Han-Sung Jung
10:20-10:30 Strategies for functional enamel formation using hiPSCs

Yonsei University
College of Dentistry, Korea

12:50-13:00 Closing Remarks

Prof. Eijiro Jimi

6th KOB & OBT Joint International Symposium 2022

Graduate Student’s Session

Chaired by Hu Chen and Tsukasa Aoki

Wnt signaling promotes tooth germ development
mediated by YAP1-TGF-β signaling
Ryoko Nagano1,2, Shinsuke Fujii1,3, Kana Hasegawa1,
Hidefumi Maeda2, Tamotsu Kiyoshima1
1

Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic andSurgical Sciences, Faculty of Dental Science, Kyushu University, Japan2
Department of Endodontology and Operative Dentistry, Division of Oral
Rehabilitation, Faculty of Dental Science, Kyushu University, Japan3
Dento-craniofacial Development and Regeneration Research Center,
Faculty of Dental Science, Kyushu University, Japan
Tooth germ development involves continuous and sequential steps with reciprocalinteractions between odontogenic epithelium and the adjacent mesenchyme. Several
growth factors, including Wnt, and their signal activation are reported to be involved in
tooth germ development. Notably, genetically modified mice with odontogenic
epithelium-dependent Wnt/β-catenin pathway activation showed developmental
anomalies of tooth germ, indicating that the appropriate activation of Wnt/β-cateninsignaling is essential for tooth germ development. However, the molecular mechanisms
underlying Wnt/β-catenin-regulated tooth germ development are poorly understood.
We recently demonstrated that Wnt/β-catenin signaling inhibited odontogenic
epithelial cell proliferation through a reduction in Semaphorin 3A (Sema3A) expression.
In tooth germ rudiments culture, Sema3A stimulation reversed Wnt/β-catenin signalingdependent decreased cell proliferation but did not completely rescue the morphologicalanomalies of tooth germ, suggesting that an uncharacterized signaling pathway may beessential in Wnt/β-catenin signaling-dependent tooth germ development. Herein, an
enrichment analysis using DNA microarray data revealed that Wnt/β-catenin signaling
negatively regulates Yes-associated protein 1 (YAP1) and/or TGF-β signaling. In
odontogenic epithelial cells and tooth germ rudiments, Wnt/β-catenin signaling reduced
YAP1 expression, thereby suppressing YAP1 and TGF-β signaling sequentially. Finally,
Wnt/β-catenin signaling-dependent disorganized tooth germ development, in which
YAP1 signaling was suppressed, was reversed by TGF-β stimulation, possibly as a resultof regulating a specific epithelial cell fate, such as stellate reticulum or outer enamel
epithelium.
These results suggest that Wnt/β-catenin signaling contributes to the tooth germdevelopment through YAP1-TGF-β signaling.

Effect of carbonate apatite as a bone substitute from the perspective ofmesenchymal stem cells
Ryosuke Takahashi1,2, Ikiru Atsuta2, Ikue Narimatsu1, Xiaoxu Zhang3,
Yuki Egashira1,2, Kiyoshi Koyano2, Yasunori Ayukawa1
1

Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation,
Faculty of Dental Science, Kyushu University, Fukuoka, Japan
2
Division of Advanced Dental Devices and Therapeutics,
Faculty of Dental Science, Kyushu University, Fukuoka, Japan3
Department of Applied Prosthodontics, Institute of Biomedical Sciences, Nagasaki
University, Nagasaki, Japan

Objective: The use of bone substitutes has become important for safe implant
treatment. Bone substitutes containing carbonate apatite (CO3Ap), a major inorganic
component of bone, have been developed in recent years. However, the detailed
mechanism by which CO3Ap acts as an effective bone substitute remains unclear. To
clarify the mechanism of CO3Ap as a bone substitute, we compared differences among
CO3Ap, hydroxyapatite (HAp), and β-tricalcium phosphate (β-TCP) by focusing on
mesenchymal stem cells (MSCs) that have a role in wound healing in the oral cavity.
Methods: In vivo experiment: 6-week-old male Wistar rats had maxillary right first andsecond molars removed, and CO3Ap, HAp, or β-TCP was inserted into the site. MSC
and macrophage accumulation as well as high mobility group box 1 (HMGB1) secretion
surrounding the extraction site were evaluated. In vitro experiment: MSCs from rats
were cultured with CO3Ap, HAp, β-TCP, or no material (control). Cell morphology,
proliferative capacity, differentiation, and expression of growth factors were evaluated.
Additionally, changes in the calcium concentration of the culture supernatant were
measured as an influential factor.
Results: In vivo experiment: Healing of extraction sockets was significantly promotedin the CO3Ap group, together with strong accumulation of MSCs and secretion of
HMGB1. Significant accumulation of macrophages was observed in the β-TCP group.
In vitro experiment: The differentiation potential and amount of calcium deposition
were significantly lower in CO3Ap and HAp groups than in control and β-TCP groups.
There was no significant difference in proliferative ability between the bone substitutes.
However, increases in IGF-I and VEGF were found only in the CO3Ap group.
Conclusion: CO3Ap-filled extraction sockets accumulate MSCs without an excessive
inflammatory reaction, and MSCs cultured in the presence of CO3Ap produce large
amounts of growth factors. These results suggest that CO3Ap as a bone substitutepromotes healing of tooth extraction sockets.

Long-term administration of bisphosphonates enhances aversive
behavioral responses to HCl.
Asami Oike1,2, Shusuke Iwata1,3, Ayaka Hirayama1, Yurika Ono1, Yuki
Nagasato1, Yuko Kawabata4,5, Shingo Takai1, Keisuke Sanematsu1,3,6,
Naohisa Wada2, Noriatsu Shigemura1,3.
1Section of Oral Neuroscience, Graduate School of Dental Science, Kyushu University,
Fukuoka, Japan; 2Section of Interdisciplinary Dentistry, Graduate School of Dental
Science, Kyushu University, Fukuoka, Japan; 3Research and Development Center for
Five-Sense Devices, Kyushu University, Fukuoka, Japan; 4Laboratory of Molecular andCellular Biochemistry, Division of Oral Biological Sciences, Kyushu University,
Fukuoka, Japan; 5Department of Cell Biology, Aging Science, and Pharmacology,
Division of Oral Biological Sciences, Faculty of Dental Science, Kyushu University,
Fukuoka, Japan; 6Oral Health/Brain Health/Total Health Research Center, Faculty of
Dental Science, Kyushu University, Fukuoka, Japan

Drug-induced taste disorders cause malnutrition and reduce the quality of life, butlittle is known about the molecular mechanism. One of taste disorders is known adverse
effects of bisphosphonates, which are administered as anti-osteoporotic drugs or antibone-resorptive and temporary. Therefore, the present study evaluated the effects ofrisedronate (a bisphosphonate) on taste bud cells. Bisphosphonates inhibit farnesyl
diphosphate synthase (FDPS), which is a key enzyme in the mevalonate pathway thatmediates cholesterol synthesis. Expression analyses revealed that FDPS was present in a
subset of mouse taste bud cells, especially type III sour-sensitive taste cells.
Behavioral analyses (short-term lick tests) revealed that mice administered risedronate
for 28 days exhibited a significant reduction in their preference for sour tastant (HCl)but not for other taste solutions (salty; NaCl, KCl, sweet; sucrose, bitter; quinine HCl,and umami; monopotassium glutamate) compared to controls. In contrast, taste nerve(the chorda tympani nerve and the glossopharyngeal nerve) responses showed nosignificant differences in responses to all taste substances. On the other hand, the taste
buds of mice administered risedronate for 28 days exhibited significantly higher mRNA
expression of FDPS and significantly lower mRNA expression of desmoglein-2, anintegral component of desmosomes. Taken together, these findings suggest thatrisedronate may interact directly with FDPS to inhibit the mevalonate pathway in type
III taste cells, thereby affecting the structure of desmosomes in the plasma membrane
related with paracellular permeability to H+ and/or Cl- in the taste buds. These findings
provide new insights into the mechanisms of FDPS in taste bud cells by whichbisphosphonates may cause taste-like disorders.

Involvement of TNF-α produced by TLR8+ monocytes/macrophages in
the initiation of Sjögren’s syndrome
Yuka Miyahara1, Masafumi Moriyama1,2, Mizuki Sakamoto1, Hu Chen1, Naoki
Kaneko1, Kazuki Kai1, Noriko Kakizoe-Ishiguro1, Akira Chinju1, Kotono Okabe-Kibe1,
Kenichi Ogata1, Takashi Maehara1, and Seiji Nakamura1
1

Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic andSurgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
2
OBT Research Center, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
Backgrounds: Sjogren’s syndrome (SS) is an autoimmune disease characterized bylymphocytic infiltration in the salivary and lacrimal glands with concomitantautoantibody production. Although the pathogenic involvement of adaptive immune
responses mediated by CD4+ T helper cells in SS is well established, recent reports havehighlighted the innate immune responses underlying in the initiation of SS. In thisstudy, we thus focused on Toll-like receptors (TLRs), which are important for innate
immunity.
Methods: Gene expression was analyzed by DNA microarrays in labial salivary glands(LSGs) from 3 patients with SS and 3 patients with mucocele as healthy control (HC).
Differentially expressed genes of TLR family were validated by real-time PCR and
immunohistochemical staining in LSGs from patient with SS (n=32) and HC (n=18).
Next, the human monocyte cell lines, U937, were stimulated by TLR8 agonist (R848)
and then measured the cytokine concentration of culture supernatant by ELISA.
Results: In SS, four genes of TLR family (TLR1, TLR7-9) were overexpressed by DNA
microarray. PCR validated significantly higher expression of TLR7 and TLR8 in SS
compared with HC. Double immunofluorescence staining showed that TLR7+ and
TLR8+ cells were mainly colocalized with CD123+ plasmacytoid dendritic cells (pDCs)
and CD68+ monocytes/macrophages in LSGs, respectively. Several studies have alreadyshown the involvement of pDCs in the pathogenesis of SS via TLR7/IFN-α signaling,
while the association of TLR8 with SS is not still unclear. Recently, it was shown that
TNF-α produced by TLR8 signaling triggered Th1-induced inflammation in otherautoimmune disease. After in vitro stimulation with TLR8 agonist, U937 increased
supernatant TNF-α concentration. Moreover, supernatant TNF-α concentration was
distinctly increased in TLR8-overexpression U937, while was significantly decreased in
TLR8-knockout U937.
Conclusion: Our current data suggest that monocytes/macrophages might be involvedin the initiation of SS by the production of TNF-α via TLR8 signaling.

Extrafollicular B cell response in two different disease milieus: IgG4relate disease and oral squamous cell carcinoma.
Hu Chen1, Naoki Kaneko1, Yuka Miyahara1, Masafumi Moriyama1,2, Seiji Nakamura1
1

Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic andSurgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
2
OBT Research Center, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
Backgrounds: Autoantibody production is one of the most characteristic features of
autoimmune diseases. Recent studies have also shown that autoantibodies are generated
by specific B cells in several types of cancer. These autoantibody-producing B cells
might have pivotal roles in the pathogenesis of autoimmune diseases and cancers, whichhave potential as a therapeutic target. However, very little is known about how to
produce the autoantibodies and those cell origins. We here showed the expansion of a
distinct specific subset of IgD-CD27- double negative (DN) B cells and the potential
ability to produce autoantibodies.
Methods: Flow cytometry was used to investigate the DN B cells in the blood frompatients with IgG4-related disease (IgG4-RD), oral squamous cell carcinoma (OSCC)
and healthy control. Then DN B cells were investigated in the FFPE tissue specimens
using multi-color immunofluorescence. The submandibular glands from patients with
IgG4-RD and chronic sialadenitis, and the resected tongue from a patient with OSCC
were dissociated into single-cell suspensions, and then immune cells were selected fordownstream single-cell RNA and BCR repertoire sequencing.
Results: IgD-CD27- CXCR5-CD11c- DN3 B cells, one subset of DN B cells, wereincreased in blood and tissue in patients with IgG4-RD and OSCC. The single-cell RNA
sequencing data showed that DN3 B cells had low expression or absence of genes
involved in germinal center response, but high expression of antibody-secreting genes.
BCR repertoire sequencing revealed that DN3 B cells were clonally expanded in IgG4RD and OSCC compared with disease control, and DN3 B cells contain low frequency
of somatic hypermutations compared with antibody secreting cells in both diseases.
Discussion: We identify DN3 B cells as a distinct B cell subset that accumulates in bothblood and tissues in patients with IgG4-RD and OSCC. In both diseases, the gene
expression pattern of DN3 B cells indicates that these specific B cells are synthesizing
antibodies and generated by extrafollicular responses with the low frequency of somatic
hypermutations. DN3 B cells are likely to have the potential to produce autoantibodies
and might contribute to the pathogenesis of autoimmune diseases and cancers.

6th KOB & OBT Joint International Symposium 2022

OBT Special Lecture (1)Chaired by Dr. Zhou Wu

Yihui CUI
Principal investigator, Doctoral supervisor, School of medicine, Zhejiang University
Dr. Yihui Cui received her Ph.D. in Neurobiology from
University of Paris 6. She was then a postdoctoral fellow at
Medical School of Zhejiang University before she was appointed
as a Principal investigator at the Center of Neuroscience. Dr. Cui
has been a member of “Hundred Talents Program” at Zhejiang
University since 2019. She has been focusing on the molecularand circuitry mechanisms of chronic stress induced depression
and made important findings (Nature, 2018a; Nature, 2018b;
Trends in Neurosciences, 2019; Neuron, 2022).
Main Publications:
1. Hypothalamus-habenula potentiation encodes chronic stress experience anddrives depression onset. Zheng Z#, Guo C#, Li M, Yang L, Liu P, Zhang X, Liu
Y, Guo X, Cao S, Dong Y, Zhang C, Chen C, Xu J, Hu H, and Cui
Y*. Neuron. 2022. (Cover)
2. Region-specific anti-Hebbian plasticity subtend distinct learning strategies in the
striatum. Perez S#, Cui Y#, Vignoud G#, Perrin E, Mendes A, Zheng Z, Touboul
J* and Venance L*. Cell report. 2022
3. Circuits and functions of the lateral habenula in health and in disease. Hu H, Cui
Y, Yang Y. Nat Rev Neurosci. 2020.
4. Lateral Habenular Burst Firing as a Target of the Rapid Antidepressant Effects
of Ketamine. Cui Y, Hu S and Hu H*. Trends in Neurosciences 2019 (Cover)
5. Decoding depression: insights from glial and ketamine regulation of neuronalburst firing in lateral habenula. Cui Y, Yang Y, Dong Y, Hu H*. Cold Spring
Harb Symp Quant Biol, 2019.
6. Astroglial Kir4. 1 in the lateral habenula drives neuronal bursts indepression. Cui Y, Yang Y, Ni Z, Dong Y, Cai G, Foncelle A, Ma S, Sang K,
Tang S, Li Y, Shen Y, Berry H, Wu S, Hu H*. Nature, 2018.
7. Ketamine blocks bursting in the lateral habenula to rapidly relieve
depression. Yang Y#, Cui Y#, Sang K#, Dong Y#, Ni Z, Ma S, Hu H*. Nature,2018.
#

equal contribution, * corresponding authorTargeting hypothalamus-habenula synapses – a novel circuitry
mechanism for prevention strategy of chronic stress induced
depression
Yihui CUI
School of medicine, Zhejiang University

Depression is a leading cause of disability worldwide and a major contributor to theoverall global burden of diseases. However, numerous studies have focused on the “cure”,
but less on the “prevention”. Among the complicated etiologies of depression, chronic
stress is a major risk factor. Stress dynamically leads to synaptic dysfunction, which canbe a potential therapeutic target for stress-related mood disorders. Given the essential roleof lateral habenula (LHb) in depression, here, we attempted to clarify how LHb-centricneural circuitry integrates stress-related information. We identified lateral hypothalamus(LH) as the most physiologically relevant input to LHb under stress. LH neurons fire witha unique pattern that efficiently drives postsynaptic potential summation and a closely
followed LHb bursting (EPSP-burst pairing) in response to various stressors. We foundthat LH-LHb synaptic potentiation is determinant in stress-induced depression.
Mimicking this repeated EPSP-burst pairings at LH-LHb synapses by photostimulation,
we artificially induced an ‘‘emotional status’’ merely by potentiating this pathway in mice.
In contrast, by de-potentiating LH-LHb synaptic transmission during chronic stress, we
successfully prevented depression onset. Notably, this de-potentiation is activity-patterndependent, timing-sensitive and relies on the activation of eCB systems. Together, wedelineated the spatiotemporal dynamics of chronic stress processing from forebrain onto
LHb in a pathway-, cell-type-, and pattern-specific manner, and discovered a novel
neuromodulation strategy on early interventions before depression onset.

6th KOB & OBT Joint International Symposium 2022

JICA Session

Chaired by Dr. Tomoyo Yasukochi

Some memorandums about International Activities
of Kyushu University Faculty of Dentistry
Minoru Nakata, PhD, Professor Emeritus
A couple of years later since I was promoted to be a professor of Kyushu University in
1979, I was appointed as the chairman of the international exchange program for entire
Kyushu University. This position gave me a very good opportunity to be acquainted
with personals who were working in regard with the international activities ingovernmental levels or easy access to the officers who were dealing with theinternational projects supported by the Government. In early 1980s, the chief officer of
JICA Kyushu Branch visited me and asked whether any specialty could contribute to
JICA Projects. So, I asked whether any dental project was being conducted and I could
know that no dental project existed. Then I tried to propose that our dental faculty may
be possible to manage the dental training course.
Then I realized that setting up of this course was no so easy as I thought. Firstly, somefaculty members did no not show any positive interests or did not like to pay extra
efforts on such activities that may not be so much academic. In next, I was surprised
when the governmental officer of the Department of Foreign Affairs that control the
JICA’s activities, told me that they had never received the requests for assistance indental fields and said if the number of applications were less than ten, this course may
not be realized.
Then I mailed this information with application papers to a lot of friends in thedeveloping countries whom I could be acquainted through my activities in FDI (World
Dental Congress) or visits to give lectures in those countries. I was very glad to knowthat most of participants in the year of 1988 when this course started, were promoted tothe higher position in each area such as academic or public health, since what theylearned at Kyushu University was evaluated.
In 1999, I planned the International Symposium on the Global Cooperation on Oral
Health at our Faculty of Dental Kyushu University. JICA supported financially thisproject, then we invited several former participants and the Heads of WHO, FDI, and
IADR as special advisors. This was very successful to make our Faculty very
impressive and active in the field of International collaboration for better oral healthpromotion for whole nations. I am sure this event gave a big momentum for Kyushu
University Faculty of Dentistry to be known, as the one which has been very eager towork with the global partners in the field of Oral Health and its science. As far as Iknow, 242 dentists participated to this course from 52 countries during 1988-2009. I
hope the participation to this course may be benefitted to not only to the participant
himself or herself also to the people of their countries.
In addition, I would like to mention my activity in concerned with OBT ResearchCenter projects. I am the first one who proposed that recent studies have shown thatmastication is of great importance, not only for the intake of food but also for thesystemic, mental and physical functions of the body.
At the FDI general assembly in the year of 2003, as a delegate from Japan Dental
Association to FDI, I proposed that we have a lot of evidences indicating the chewing
function gives good effects on general health and proposed that the FDI should approve
this and transfer to all dental associations about these facts. My proposal was that FDI
should adopt that Effect of Masticatory ability on general health, as the official
statement of FDI for all over the world. This proposal caused a lot of debates and thedecision was postponed until the last day assembly of FDI Annual Meeting, where thedecision was undertaken by votes by representatives of dental associations from eachcountry and finally this proposal was adopted. You can see this in the home page of FDI
official site.

FLOW OF LIFE WITH AND WITHOUT KYUSHU UNIVERSITY
Comparison Of The Effect Of Proanthocyanidin Surface Treatments On Shear
Bond Strength Of Different Cements
A. Nehir Özden1, Şifa Atabek2
Department of Prosthodontics, Faculty of Dentistry, Eastern Mediterranean University,
Cyprus1.
Department of Prosthodontics, Faculty of Dentistry, Final International University,
Cyprus2.
Participation to the course of JICA in Kyushu University enriched not only myacademic but social life also. While we were learning Japanese culture and science andtechnology in dental school of Kyushu University, because of the multicultural structureof course participants I experienced different behaviours also which I remember with asmiling face.
I have worked many different subjects of dentistry and one of my latest study was a
PhD thesis ‘’ Comparison Of The Effect Of Proanthocyanidin Surface Treatments On
Shear Bond Strength Of Different Cements’’.
Cements for prosthodontic restorations advanced and application techniques developed.
Minimally invasive approach within dentistry created a new demand in the use ofrestorative properties at the micro- and macro-level, and this perspective also had aneffect on bioactive cements. A bioactive material is defined as a substance that results inthe formation of an apatite-like material as a surface layer in the presence of a simulated
body fluid.
This study aimed to compare the effect of proanthocyanidin-rich grape seed extract(Pa-rich GSE) in two different concentrations (6.5% &12.5% ) on the bond strength todentin tissue for four different cement groups (resin cement (P), resin modified glassionomer cement (K), calcium aluminate glass ionomer cement (C), glass ionomer
cement (G).
As a result; Resin cement showed higher bond strength to dentin than other cements(P12.5: 15.08 ) . The application of the extract containing 6.5% proanthocyanidin to
dentin surfaces increased the bonding of conventional glass ionomer cement to dentin.
While there was no difference in dentin–cement bonding between resin and calcium
aluminate glass ionomer cement by applying 12.5% Pa-rich GSE to dentin surfaces,
resin modified, and conventional glass ionomer cement weakened dentin bonding.
Calcium aluminate glass ionomer cement showed similar shear bond strength values
with other cements except resin cement.
According to these results, as an alternative to resin modified glass ionomer cement andglass ionomer cement, calcium aluminate glass ionomer cement can be tried in clinicalstudies, and more studies can be done with glass ionomer cements and 6.5% Pa-rich
GSE.
Keywords: Grape seed extract; Dental cements; Shear strength; Bioactive material;
Proanthocyanidin

6th KOB & OBT Joint International Symposium 2022

OBT Special Lecture (2)Chaired by Prof. Eijiro Jimi

Osteoblast Lineage-Specific Cell-Surface Antigen Regulating Osteoclastogenesis
and Calcification: A Possible New Player in Bone Remodeling
Tamer Badawy1,2, Yukari Kyumoto-Nakamura 3, Norihisa Uehara 3, Jingqi Zhang 3,
Takayoshi Yamaza3, Akiko Kukita4 and Toshio Kukita3
1. Department of Oral Biology, Faculty of Denistry, Cairo University, Egypt.
2. Department of Oral Biology, Faculty of Denistry, Galala University, Egypt.
3. Department of Molecular Cell Biology and Oral Anatomy, Faculty of Dental Science, Kyushu
University, Japan.
4. Department of Microbiology, Faculty of Medicine, Saga University, Nabeshima, Saga, Japan.

(Purpose) Bone remodeling is a dynamic lifelong process involving interactions
between various bone cells in a precisely coordinated manner at specific multi-cellularunits. Osteoclasts play a pivotal role in bone remodeling. Although RANKL/RANK
axis is considered the major factor determining the total number of osteoclasts in bone
tissues, detailed molecular events regulating the efficiency of bone remodeling are still
obscure. We postulated that osteoblast-specific cell-surface molecules could haveregulatory roles in bone remodeling. Therefore, we carried out an extensive
immunological survey searching for such molecules. In the course of our survey, we
identified a unique antigen (A7 antigen) highly specific to cells in the osteoblastlineage. We described on the detailed expression pattern of A7 antigen in vitro and invivo and its possible role in modulating bone remodeling.
(Materials and Methods) BALB/c mice were immunized with a clone of the rat
osteoblastic cell line ROS17/2.8. Hybridomas were formed by fusing splenocytes withmurine myeloma cell line (P3X63-AG8-U1). Antibodies of each hybridoma were
initially screened by staining of rat bone marrow, osteoblast cell line, mesenchymal
stem cells. The osteoblast-specific hybridoma was selected and extensively cloned toobtain hybridoma secreting anti-A7 monoclonal antibody (A7 MAb). Immunoreactivityof A7 MAb was examined using cultures of osteoblasts and bone marrow cultures andby use of bone tissue sections. Bioactivity of this MAb was assessed using in vitro
calcification system of primary calvarial-derived osteoblasts and bone marrow cultures
for forming osteoclasts.
(Results and conclusions) In vitro, A7 antigen showed typical cell-surface expression
pattern in osteoblast cell line and bone marrow stromal cells. In vivo, the antigen
showed membrane expression in a subset of bone surface osteoblasts and in osteocytes.
Tissue array studies demonstrated preferential expression of A7 antigen on cell-surfaceof osteocytes located just close to the bone surface. Immunoblotting revealed that A7
antigen was lineage-specific of approximate molecular weight of 45 KDa.
Immunoprecipitation of A7 antigen from biotinylated osteoblast cell-surface proteins
also resulted in a single band of 45 KDa protein. Cross-linking of A7 antigen with A7
MAb completely abrogated calcification in cultures of primary calvarial-derived
osteoblasts and slightly stimulated osteoclasogenesis in bone marrow cultures. A7
antigen could be an important regulator of osteoclast recruitment and osteoblast
differentiation and calcification and could be useful in the development of novel
therapeutic approaches for treatment of bone diseases.

6th KOB & OBT Joint International Symposium 2022

KOB Session

Chaired by Prof. Eijiro Jimi

CURRICULUM VITAE
Kaan Orhan, DDS MSc MHM PhD, BBAc is the Dean and a
Professor of DentoMaxilloFacial Radiology at the Ankara
University, Faculty of Dentistry, where he serves as a faculty in
Dentomaxillofacial Radiology Department, Ankara University,
Ankara, Turkey, and visiting Professor at the Medical
University of Lublin, Poland and was also visiting Professor
between 2018-2020 at the OMFS-IMPATH Research Group,
Department of Imaging and Pathology, University of Leuven,
Belgium. He is currently also a visiting Professor at the Lublin
University Faculty of Medicine in Poland.
Dr. Orhan received his dental degree in 1998 and completed his
PhD and Maxillofacial radiology residency studies in 2002 at the Osaka University
Faculty of Dentistry in Osaka, Japan and Ankara University, Faculty of Dentistry. In 2004,
he started his academic career in Ankara University as a consultant at the Faculty of
Dentistry. Between 2004-2006, he worked as Maxillofacial consultant and lecturer in thesame University. He became an associate professor in 2006 and a full-time professor in2012. 2007-2010, he was the founder and the chairman of Dentomaxillofacial Radiology
Department, Near East University, Cyprus.
He has over 350 SCI international publications on peer-reviewed journals, and received
over 5000 citations from his studies with an h index 40. He particularly made significant
contributions in the Maxillofacial Radiology. He has been invited to give many lecturesin national and international scientific meetings. He served as the chairman of Researchand Scientific Committee, European Academy of DentoMaxillofacial Radiology(EADMFR) between 2008-2012 and he was elected for the Vice president position (20122014) and then as the President of EADMFR.
He is also still serving in the Research and Scientific com in IADMFR. He is a fellow ofAmerican Academy of Oral and Maxillofacial Radiology (AAOMFR), Japanese Boardof DentoMaxillofacial Radiology, European Head and Neck Radiology Society (ESHNR),
European society of Magnetic Resonance in Medicine and Biology (ESRMB), Turkish
Magnetic Resonance Society,He was a Board member of specialization committee in Ministry of Health and served as
the recognition of Dentomaxillofacial Radiology specialty in Turkey. He is editor ofseveral journals and also reviewer more than 50 different medical journals. He is coauthor and contributor of more than 10 books both in English and Turkish.
Prof. Dr. Kaan Orhan was included in the "World's Most Influential Scientist" list, which
was published by Stanford University in 2021, at the rate of 2% according to academic
and scientific performance among 7 million researchers all over the world. In 2020, he
received the "Innovative Dentist of the Year" award with his work titled Artificial
Intelligence Application in Dentistry. Besides, The Lincoln R. Manson-Hing Honorable
Mention Award given by the Oral Maxillofacial Radiology Association of America in2018 and 2019, and the Ankara University Science Award in 2018, the Turkish Dental
Society Oral and Dental Health 2nd Prize in 2015, and the "52nd Prize in Dental Health"in 2011. Japanese Congress of DentoMaxillofacial Radiology”. He received the European
Congress of DentoMaxillofacial Radiology”, the best study award in 2008. "Yoshida
Manufacturing Award" at the "7th Asia Oral and Maxillofacial Radiology" congress in2008.

Artifical Intelligence and Blockchain in Dentistry and Radiology:
What does the future hold?
Prof. Dr. Kaan ORHAN
Ankara University Faculty of Dentistry Department of Dentomaxillofacial Radiology,
Ankara, TURKEY

Abstract
Artificial intelligence (AI) in healthcare is the use of algorithms and software toapproximate human cognition in the analysis of complex medical data. Specifically, AI
is the ability for computer algorithms to approximate conclusions without direct human
input. What distinguishes AI technology from traditional technologies in health care is
the ability to gain information, process it and give a well-defined output to the end-user.
AI does this through machine learning algorithms, which can recognize patterns inbehavior and create its own logic. This lecture explains the basic principles of deeplearning and its application as well blockchain technology will be discussed technicalrequirements, and presents examples of successful application of deep learningtechniques in dentistry and radiology based on our clinical studies.
Keywords: Artifical Intelligence, Block chain, health, NFT, IoT

Prevalence and predictors of bruxism patients with dental implants: a symptombased diagnosis and prevention strategy
Volkan Arısan
Department of Oral Implantology, Faculty of Dentistry, Istanbul University, Capa,
Istanbul, Turkey

Involuntary clenching and/or bracing of the teeth -bruxism- can yield detrimental effects
on the stomatognathic system. Despite the growing number of patients carrying dental
implants the frequency, indicators and the consequences of bruxism is not yet fully
understood. In to determine the prevalence of bruxism a survey including clinical andpatient-reported findings was conducted and 1688 patients with a total of 1856
prostheses supported by 4702 implants were analyzed. 54.04% of the prostheses
experienced complications consisting of 1003 technical and 353 mechanicalcomplications. 333 patients (19.72%) identified as a probable bruxer. Besides selfreported bruxism (p < 0.022), antidepressant use (p < 0.002), frequent headaches(p < 0.014), and observation of linea alba (p < 0.028) were the predictors for probablebruxism. Technical and mechanical complications were frequent in the probable bruxers(p < 0.05). In this lecture diagnostic predictors of bruxism will be discussed withrelation to potential prevention strategies in patients with dental implants.

Jordan University of Science and Technology (JUST) isan honored academic and research center that is committed to giving
students a stimulating learning environment and a welcoming community.
Among Jordanian universities, JUST is the jewel. As a part of acommunity of researchers, who are working to improve the education, andindustry in Jordan and the region through research, worldwide scientificassociations as well as local community involvement , JUST has given its
major priority to academic research. The Deanship of Research started its
activities at the early stages of the University establishment during theacademic year 1986/1987. It works in passion to recognize, encourage, andreward success and quality in research and development by creating a
research environment that encourages both basic and applied research.
The annual reports through years showed a noticeable gradualimprovement in the field of research in JUST . A distinguished research
publication rate was recorded in the last few years in comparison with thenational universities recorded rates. The following diagram showed thatproudly.

Regarding dentistry field, JUST supports dentistry research financiallyand scientifically. And the faculty itself provides the researchers withall the facilities needed either equipment, machines and materials. In
addition, an appreciated role of faculty staff members in research canbe highlighted in all dentistry specialties. The scientific environmentthat is provided by the university and the faculty encourages the staff
members to keep up the good work in research field with passion.
In addition, JUST provides MClinDent degrees in six specialties. These
programs are: Fixed and Removable Prosthodontics, Restorative
Dentistry, Periodontics, Endodontics , Orthodontics and Pediatric
Dentistry. To achieve the full certificate in the specialty, residents are
obligated to go through a full formal research experience (master’s
thesis ) including article submission after thesis defense under thesupervision of staff members.

ABSTRACTIn Vitro immunomodulation of Human Periodontal Ligament Stem Cells on
Dendritic Cells Phenotype and Function in Type 1 Diabetes

Rola Alhabashneh
Jordan University of Science and Technology (JUST), Jordan

Background: Human periodontal ligament stem cells (PDLSCs) have recently beenfound a viable source of mescenchymal stem cells with properties similar to those seen
in bone marrow stromal stem cells (BMSSCs). Their ability to modulate dendritic cellDCs phenotype and function along with with its immunosuppressive effects on othercells of the immune system makes an investigation of PDLSCs effect in type 1 diabetes
context worth pursuing Aim: The aim of this study is to understand the immunological
function of human PDLSCs in DC-mediated T-cell immune responses and if they areable to modulate the islet β-cell destruction. This is done by evaluating whether
periodontal ligament stem cells PDLSCs have an effect on the phenotype,
differentiation and maturation of monocyte-derived DCs isolated from T1DM patients.
Furthermore, this work aims to investigate the effect on gene profile for selected
immunoregulatory and immunostimulatory cytokines. Material and methods: Maturedendritic cells from type 1 diabetic patients are derived from monocytes, characterized
by flow cytometry at different stages (monocyte, immature DCs, and mature DCs) fromfour donors. mDCs where then co-culured with PDLSCs for two days and changes inlevel of maturation and costimulatory molecules measured by flow cytometry. qPCR
was then done to analyse the gene transcription profile of co-cultured mDCs incomparison to mDCs in terms of their upregulation or downregulation of IL-6, IL-10,
TGF-b, IL-1b, TNF-a Results: PDLSCs exerted an immunosuppressive effect on fully
mature dendritic cells by significantly reducing expression of all maturation markers. A
significant upregulation of the immunoregulatory cytokine IL6 and a significant
downregulation of immunostimulatory cytokine TNF-a was also noted.
Conclusion: this in vitro study provides strong evidence of the immunomodulatory
capacities of PDLSCs in T1DM context

The Association between Anti-Asthma Medications and Periodontal HealthObjective: The present study aims to assess clinical and inflammatory parameters as
indicators for periodontal disease in patients with bronchial asthma who are on a
combination of inhaled corticosteroids and long acting beta 2 agonists, and those on
regular short acting beta 2 agonist.
Methods: 116 patients visiting the outpatient pulmonary clinics were divided into fourgroups according to the used medications. BA was diagnosed by a pulmonary
consultant and being on inhaled asthma medication for at least 12 months. Participants
were examined for clinical periodontal parameters and samples of saliva were taken andanalyzed for the acidity of saliva, un-stimulated whole salivary flow rate and for thelevels of 4 different inflammatory cytokines.
Results: Compared with controls, asthma groups had significant higher mean gingivalindex (GI) (p = 0.001). Also, the occurrence of periodontitis was significantly higher
among asthma patients compared to non-asthma participants (p=0.006). Asthma patients
who were treated by inhaled corticosteroids had significantly lower salivary flow ratecompared to asthma patient who were used short acting beta 2 agonists (SABA) who
had also lower salivary flow rate compared to control participants (0.5, 0.7, 0.9 ml/ min,p < 0.001). The levels of IL-1β and MCP-1 were significantly higher in the asthma
group compared to the control group (p<0.05). The level of hsCRP was significantly
higher in asthma groups who treated by inhaled corticosteroids compared to the othergroups (p<0.001). Obese patients had significantly higher concentration of hsCRP
compared to non-obese patients (p<0.001). There was no significant difference in thelevel of MMP-8 between groups.
Conclusions: Patients with bronchial asthma especially those on inhaled corticosteroids
are at increased risk of having periodontitis. This association was supported by theincreased level of local pro-inflammatory cytokines which might have local andsystemic inflammatory burden.

6th KOB & OBT Joint International Symposium 2022

Award Lectures

Chaired by Prof. Hidefumi Maeda
and Prof. Tamotsu Kiyoshima

RAF1–MEK/ERK pathway-dependent ARL4C expression promotes
ameloblastoma cell proliferation and osteoclast formation
Shinsuke Fujii1,2, Eijiro Jimi3,4, Tamotsu Kiyoshima1
1

Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences,2
Dento-craniofacial Development and Regeneration Research Center,
3
Oral Health/Brain Health/Total Health Research Center,
4
Laboratory of Molecular and Cellular Biochemistry, Division of Oral Biological Sciences,
Faculty of Dental Science, Kyushu University, Japan.

Ameloblastoma is an odontogenic neoplasm characterized by intraosseous slow growthwith progressive bone resorption of the jaw. Recent reports have demonstrated thatameloblastoma harbors an oncogenic BRAF V600E mutation with MAPK pathway
activation. Recently, we have examined the expression and function of ADP-ribosylation
factor (ARF)-like 4c (ARL4C), a member of small GTP-binding superfamily, in the oral
fields, especially in tumorigenesis and morphogenesis. ARL4C expression is reportedly
induced by EGF/Ras signaling, and ARL4C overexpression, due to its signaling
alterations, is involved in tumorigenesis. However, ARL4C expression and function in
ameloblastoma remain unclear. Here, we conducted to investigate the expression of
ARL4C in human ameloblastoma tissue specimens and elucidate its function in
ameloblastoma cell line (AM-1). Immunohistochemical analyses demonstrated that
ARL4C was strongly expressed in tumor lesions at high frequencies alongside theexpression of both BRAF V600E and RAF1 (also known as C-RAF). The experiments
using siRNA and inhibitors revealed that ARL4C expression depended on RAF1-MAPK,
but not BRAF V600E mutation in ameloblastoma cell line. ARL4C-depleded AM-1 cells
using CRISPR/Cas9 system showed a decrease of cellular growth and osteoclast
formation when AM-1 was co-cultured with mouse bone marrow cells and primaryosteoblasts. These results suggest that RAF1-MEK/ERK-mediated ARL4C expression
promotes ameloblastoma cell proliferation and osteoclast formation.
These results lead to the conclusion that the RAF1-MEK/ERK-ARL4C axis,
which may function in cooperation with the BRAF V600E-MEK/ERK pathway,
promotes ameloblastoma development. It is therefore intriguing to speculate thatcooperative activation of BRAF V600E and RAF1 would be the etiology ofameloblastoma cell proliferation and that such cooperative activation might induce theclinical aggressiveness of ameloblastoma beyond the category with benign neoplasia.

Regeneration of glomerular metabolism and function by podocyte
pyruvate kinase M2 in diabetic nephropathy
Takanori Shinjo1, Hisashi Yokomizo2, George L King3, Fusanori
Nishimura1
1

Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science,
Kyushu University, Fukuoka, Japan2
Department of Endocrinology and Diabetes Mellitus, Fukuoka University Hospital,
Fukuoka, Japan
3
Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA.

Diabetic Nephropathy (DN) is the major cause of end-stage kidney disease (ESKD) in
people with diabetes, affecting 30% of patients with diabetes. DN arises from systemic
and local changes in glucose metabolism and hemodynamics. In people with type 1
diabetes, hyperglycemia is the major risk factor for DN since glycemic control can
prevent and delay its progression. Podocyte loss in DN is related to the duration andseverity of hyperglycemia, and it correlates with the progression of DN. It has reported
that many glycolytic and mitochondrial enzymes, such as pyruvate kinase M2 (PKM2),
were elevated in renal glomeruli of DN-protected patients with type 1 and 2 diabetes(Gordin et al., Diabetes Care, 2019, Qi et al., Nat Med, 2017).
Here, mice with PKM2 overexpression specifically in podocytes (PPKM2Tg) weregenerated to uncover the renal protective function of PPKM2Tg as a potential therapeutictarget that prevented elevated albumin/creatinine ratio (ACR), mesangial expansion,
basement membrane thickness, and podocyte foot process effacement after 7 months of
streptozotocin-induced (STZ-induced) diabetes. Furthermore, diabetes-induced
impairments of glycolytic rate and mitochondrial function were normalized in diabetic
PPKM2Tg glomeruli, in concordance with elevated Ppargc1a and Vegf expressions.
Restored VEGF expression improved glomerular maximal mitochondrial function indiabetic PPKM2Tg and WT mice. Mechanistically, the preservations of mitochondrial
function and VEGF expression were dependent on tetrameric structure and enzymatic
activities of PKM2 in podocytes.
In this presentation, we report that PKM2 structure and enzymatic activation in
podocytes can preserve the entire glomerular mitochondrial function against toxicity ofhyperglycemia via paracrine factors such as VEGF and prevent DN progression.

Targeted inhibition of EPAS1–driven IL-31 production
by a small-molecule compound
Yasuhisa Kamikaseda1, Seiji Nakamura1, Yoshinori Fukui2,31

Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic andSurgical Sciences, Faculty of Dental Science, Kyushu University, 2 Division of
Immunogenetics, Medical Institute of Bioregulation, Kyushu University, 3 ResearchCenter for Advanced Immunology, Kyushu University

Graphical Abstract; An overview of mechanisms of IPHBA identified as a small-molecule inhibitor
targeting EPAS1-driven IL-31 production.
Highlights
・ IPHBA was identified as a small-molecule inhibitor of IL-31 (interleukin-31) production.
・ IPHBA inhibits IL-31 induction in murine and human helper T cells without affecting other cytokine
productions and hypoxic responses.
・ IPHBA inhibits the association between EPAS1 and SP1 and impairs recruitment of both transcription
factors to the specific sites of IL31 promoter.
【Introduction】Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by recurrent
eczematous legions and intense itch. Although itch can be induced by various chemical mediators, IL-31 isa major pruritogen associated with AD. A specific antibody for IL-31 receptor has been shown to alleviate
pruritus in patients with AD, however, therapeutic approaches to inhibit IL-31 production remain
unexploited. IL-31 production by helper T cells critically depends on the transcription factor EPAS1.
Therefore, EPAS1–mediated IL-31 promotor activation might be a drug target for treatment of ADassociated itch. In this study, we aimed at developing small-molecule inhibitors that selectively block IL31 production.
【 Methods 】 We generated the reporter cell line that inducibly expressed EPAS1 in the presence of
doxycycline to mediate Il31 promoter activation, and screened 9,600 chemical compounds. The selectedcompounds were further examined using helper T cells from a spontaneous mouse model of AD and thosefrom patients with AD.

【Results】We have identified (E)-4-(2-(4-isopropylbenzylidene)hydrazinyl)benzoic acid (IPHBA) as an
inhibitor of Il31 induction. Although IPHBA did not affect non-specific T cell proliferation, IPHBA
inhibited antigen–induced Il31 induction in helper T cells from Dock8–/– AND Tg mice without affecting
Il2 and Il4 induction. Similar results were obtained when helper T cells from AD patients were treated with
IPHBA. Mechanistically, IPHBA inhibited recruitment of EPAS1 to the specific site of Il31 promoter
region.
【Discussion】We have shown that IPHBA selectively inhibits IL-31 induction without affecting othercytokine productions and hypoxic responses. IPHBA could be a lead drug to inhibit EPAS1-driven IL-31
production and treat AD–associated itch.

CD163+ M2 macrophages promote fibrosis in IgG4-related disease via
TLR7/IRAK4/NF-κB signaling.
Akira Chinju1, Masafumi Moriyama1,2, Noriko Kakizoe-Ishiguro1, Hu Chen1, Yuka
Miyahara1, ASM Rafiul Haque3, Mizuki Sakamoto1, Kazuki Kai1, Kotono Kibe1,
Sachiko Hatakeyama-Furukawa1, Miho Ito-Ohta1, Takashi Maehara1, Seiji Nakamura1
1

Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic andSurgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
2
OBT Research Center, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
3
Udayan Dental College, Rajpara, Bangladesh.
ABSTRACT
Backgrounds: IgG4-related disease (IgG4-RD) is characterized by elevated serum IgG4
and marked fibro-inflammatory conditions that can affect multiple organs. We
previously reported that human Toll-like receptor 7-transgenic C57BL/6 (huTLR7 Tg)
mice showed elevated serum IgG1 (equaled to human IgG4) levels and inflammation
with fibrosis in the salivary glands (SGs), lungs, and pancreas. Moreover, we observed
extensive TLR7-positive CD163-positive M2 macrophage infiltration in SGs from
IgG4-RD patients. However, fibrotic mechanism via the TLR-7 pathway remains
unclear. In this study, we thus examined the downstream of TLR-7 and the mechanismof fibrosis in IgG4-RD.
Methods: Gene expression in SGs from huTLR7 Tg mice and IgG4-RD patients wasanalyzed using DNA microarrays. Common up-regulated TLR-7-related molecules in
SGs from huTLR7 Tg mice and IgG4-RD patients were validated by real-time PCR and
immunohistochemical staining in SGs from patient with IgG4-RD (n=15), Sjögren’s
syndrome (SS) (n=15), chronic sialadenitis (CS) (n=15), and controls (n=15). Next,
CD163-positive M2 macrophages isolated by peripheral blood mononuclear cells fromhealthy controls were stimulated by TLR7 agonist (loxoribine), and then measured thecytokine concentration of culture supernatant by ELISA. Finally, we investigated theinteraction between CD163-positive M2 macrophages and fibroblast. before and after
stimulation with loxoribine.
Results: In both huTLR7 Tg mice and IgG4-RD patients, interleukin-1 receptorassociated kinase 3 (IRAK3) and IRAK4 were significantly overexpressed by DNA
microarray. Real-time PCR validated the up-regulation of only IRAK4 in IgG4-RD
patients compared with the other groups (P<0.05). IRAK4 was strongly detected in andaround germinal centers in SGs from patients with IgG4-RD alone. Double
immunofluorescence staining showed that IRAK4-positive cells were mainly
colocalized with CD163-positive M2 macrophages in SGs (P<0.05). After stimulation
with loxoribine, CD163-positive M2 macrophages exhibited significantly enhanced
expression of IRAK4 and NF-κB and increased supernatant concentrations of fibrotic
cytokines (IL-1b and TGF-b). Finally, we confirmed that the number of fibroblasts wasincreased by culture with the supernatant of CD163-positive M2 macrophages
following stimulation with loxoribine (P<0.05).
Conclusion: CD163-positive M2 macrophages promote fibrosis in IgG4-RD byincreasing the production of fibrotic cytokines via TLR-7/IRAK4/NF-κB signaling.

6th KOB & OBT Joint International Symposium 2022

DDR Session

Chaired by Prof. Takayoshi Yamaza

Regulation of tooth development by Epiprofin
Takashi Nakamura1, Minoru Wakamori1,
and Satoshi Fukumoto,2,31Division of Molecular Pharmacology & Cell Biophysics, Department of Disease

Management Dentistry, and 2Section of Pediatric Dentistry, Division of Oral Health,Growth and Development, Kyushu University Faculty of Dental Science, Fukuoka, Japan,
3

Division of Pediatric Dentistry, Department of Oral Health and Development Sciences,
Tohoku University Graduate School of Dentistry, Sendai, Japan,

The balanced synchronization of cell proliferation, cell differentiation, andcell migration of dental epithelial and mesenchymal cells is required for the toothmorphogenesis with the functional shapes and optimum sizes. This synchronization isprecisely operated by the reciprocal interaction between the dental epithelium anddental mesenchyme in tooth development. Epiprofin (Epfn), a transcription factor
belonging to the Sp family, regulates the number of teeth as well as dental epithelial cellproliferation and differentiation into ameloblasts. Epfn deficiency results in the lack ofenamel and the development of an excess number of teeth and Epfn overexpression
driven by epithelial specific promoter induces ectopic enamel formation and reductionof missing teeth. The results of the analysis of abnormal dental phenotypes in thesemutant mice suggest that Epfn play important roles in tooth development by regulating
the synchronization of cell proliferation, cell differentiation, and cell migration of dental
epithelial.
In this presentation, we discuss about the mechanism of abnormal toothformation in Epfn mutant mice based on recent findings on the molecular regulation of
signaling pathways interacting with Epfn in epithelial cells.

Strategies for functional enamel formation using hiPSCs
Han-Sung Jung
Division in Anatomy and Developmental Biology, Department of Oral Biology, Taste
Research Center, Oral Science Research Center, BK21 FOUR Project,
Yonsei University College of Dentistry, Seoul, Korea

Tooth enamel is the highly mineralized tissue of the body, but it is well-known not toregenerate. An ideal solution for enamel regeneration is using patients’ cells. Human
induced pluripotent stem cells (hiPSCs) have emerged as a promising bioengineering
source for organ replacement, with great potential for treating incurable diseases.
Recently, many studies have kept investigating efforts to regenerate functional tooth
enamel using hiPSC, which is still not established yet. Also, yet, hiPSC-derived dentalorganoids have not been reported. This study confirmed the optimal 2D and 3D culture
protocol to induce differentiation for dental epithelial cells (hDECs) and dental epithelialorganoids (hDEOs) from hiPSCs without the animal-derived factors and cell feeders for
future clinical application. For hDECs differentiation with enamel deposition, we
attempted to increase the efficiency and proliferation of DECs by BMP-Noggin
modulation. To fabricate mineralized hard tissues, including bone and tooth, we
considered extracellular matrix microenvironments, such as GelMA, collagen, and agar
matrix. Recombination of hiPSC-derived dental epithelial cells and dental mesenchymal
cells encapsulated in ECM led to various mineralized tissue lineage.
Furthermore, to establish a 3D dental organoid culture system, the ectodermal cells fromEBs were collected, dissociated into single cells, and seeded in Matrigel with adifferentiation medium. hDEOs derived from hiPSCs had the characterization of dental
epithelial cells as well as ameloblasts. In conclusion, our findings provide a suitable
hiPSC-derived dental epithelial cell source using both 2D and 3D cultures for tooth
regeneration, especially enamel regeneration. These results will be a new insight that canbe used in multiple regenerative medicine fields.