DPSCs regulate epithelial-T cell interactions in oral submucous fibrosis.

BACKGROUND: Oral submucous fibrosis (OSF) is a precancerous lesion characterized by fibrous tissue deposition, the incidence of which correlates positively with the frequency of betel nut chewing. Prolonged betel nut chewing can damage the integrity of the oral mucosal epithelium, leading to chronic inflammation and local immunological derangement. However, currently, the underlying cellular events driving fibrogenesis and dysfunction are incompletely understood, such that OSF has few treatment options with limited therapeutic effectiveness. Dental pulp stem cells (DPSCs) have been recognized for their anti-inflammatory and anti-fibrosis capabilities, making them promising candidates to treat a range of immune, inflammatory, and fibrotic diseases. However, the application of DPSCs in OSF is inconclusive. Therefore, this study aimed to explore the pathogenic mechanism of OSF and, based on this, to explore new treatment options. METHODS: A human cell atlas of oral mucosal tissues was compiled using single-cell RNA sequencing to delve into the underlying mechanisms. Epithelial cells were reclustered to observe the heterogeneity of OSF epithelial cells and their communication with immune cells. The results were validated in vitro, in clinicopathological sections, and in animal models. In vivo, the therapeutic effect and mechanism of DPSCs were characterized by histological staining, immunohistochemical staining, scanning electron microscopy, and atomic force microscopy. RESULTS: A unique epithelial cell population, Epi1.2, with proinflammatory and profibrotic functions, was predominantly found in OSF. Epi1.2 cells also induced the fibrotic process in fibroblasts by interacting with T cells through receptor-ligand crosstalk between macrophage migration inhibitory factor (MIF)-CD74 and C-X-C motif chemokine receptor 4 (CXCR4). Furthermore, we developed OSF animal models and simulated the clinical local injection process in the rat buccal mucosa using DPSCs to assess their therapeutic impact and mechanism. In the OSF rat model, DPSCs demonstrated superior therapeutic effects compared with the positive control (glucocorticoids), including reducing collagen deposition and promoting blood vessel regeneration. DPSCs mediated immune homeostasis primarily by regulating the numbers of KRT19 + MIF + epithelial cells and via epithelial-stromal crosstalk. CONCLUSIONS: Given the current ambiguity surrounding the cause of OSF and the limited treatment options available, our study reveals that epithelial cells and their crosstalk with T cells play an important role in the mechanism of OSF and suggests the therapeutic promise of DPSCs.

[Clinical evaluation methods for craniovertebral junction abnormalities].

Craniovertebral junction malformation is a congenital malformation located in the foramen magnum and upper cervical spine, including bone and nerve malformation, resulting in motor and sensory disorders, cerebellar and lower cranial nerves, etc. The evaluation methods of clinical symptoms and efficacy of craniovertebral junction malformation are important for the surgical indications and effects, mainly including the evaluation of clinical symptoms and the quality of life. At present, the commonly used methods in clinical work and literature are the Japanese orthopaedic association scores, visual analogue scales, 36-item short-form health survey, etc. Most of these clinical evaluations are not aimed at craniovertebral junction diseases but focus on the description of a certain type of clinical symptoms. Chicago Chiari outcome scale and syringomyelia outcome scale of Xuanwu hospital are dedicated to Craniovertebral junction malformation, but more clinical studies are needed to prove their effectiveness. Based on the literature reports, this article reviewed the previous clinical evaluation methods of craniovertebral junction malformation and discusses their applications and limitations.

[Diagnosis and antidiastole of leukemia-associated gingival lesions].

Leukemia is a heterogeneous group of hematological disorders that arises from a hematopoietic stem cell characterized by a disordered differentiation and proliferation of neoplastic cells. The prevalence of leukemia is high in juveniles and adults under 35 years. Gingival manifestations of leukemia include gingiva bleeding, enlargement, pallor, petechial, ulceration, which may be the first clinical signs of leukemia. In the dental clinic, identification of leukemia-associated gingival lesions, referring patients to hematologists without delay will improve the prognosis of leukemia. Diagnosis and antidiastole of leukemia-associated gingival lesions have been discussed with reference to the related cases.

Unilateral biportal endoscopic spine surgery for lumbar spinal stenosis: a systematic review and meta-analysis.

OBJECTIVE: Lumbar spinal stenosis is the most common spinal degenerative disease in patients over 60 years, and the unilateral biportal endoscopic (UBE) spine surgery treatment of lumbar spinal stenosis (LSS) has achieved preliminary clinical results. This systematic review and meta-analysis aimed to reveal the clinical efficacy of UBE for LSS and provide evidence for clinical practice. MATERIALS AND METHODS: PubMed, Embase, Web of Science, and Cochrane databases were searched for literature. The papers selected were those published from inception till October 2021. The selected pieces of literature were graded for evidence using the Oxford Centre for Evidence-Based Medicine: Levels of Evidence (March 2009). Outcomes measures were operation time, blood loss, complication rate, admission period, Visual Analogue Scale (VAS)-back, VAS-leg, and Oswestry Disability Index (ODI) score, and radiological outcomes. The mean comparisons were based on VAS and ODI scores. RESULTS: A total of 823 patients with a single LSS segment were included from the selected nine studies. There were nine studies comparing UBE clinical outcomes and micro-endoscopic unilateral laminotomy for bilateral decompression (M-ULBD). The meta-analysis revealed that the UBE group had better VAS-leg and -back scores in the first week postoperatively [total: mean difference (MD) = -0.96, 95% confidence interval (CI): -1.19, -0.74, p < 0.00001; total: MD = -1.69, 95% CI: -1.93, -1.45, p < 0.00001], 1st month postoperatively (total: MD = -0.35, 95% CI: -0.61, -0.08, p = 0.01; total: MD = -0.40, 95% CI: -0.68, -0.12, p = 0.005), 6th month postoperatively (total: MD = -0.22, 95% CI: -0.35, -0.08, p = 0.002; total: MD = -0.24, 95% CI: -0.40, -0.07, p = 0.005), and UBE group also performed better in ODI score at 1st month postoperatively (total: MD = -3.36, 95% CI: -4.26, -2.46, p < 0.00001). There was no significant difference in VAS-leg and -back scores between both groups at the 3rd and 12th month postoperatively, and ODI scores did not significantly differ between both groups at 3, 6, and 12 months postoperatively (all p > 0.05). CONCLUSIONS: UBE has achieved good preliminary clinical results and may be a minimally invasive alternative surgery for patients with single segmental LSS.

[Silenced ANP32A inhibits the growth, invasion and migration of colorectal cancer in vitro via the inactivation of AKT pathway].

OBJECTIVE: To investigate the effect of ANP32A silencing on invasion and migration of colon cancer cells and the influence of the activity of AKT signaling pathway on this effect. METHODS: Colorectal cancer HCT116 and SW480 were transfected with a small interfering RNA targeting ANP32A via a lentiviral vector. At 24, 48 and 72 h after the transfection, the changes in cell proliferation and AKT activity in the cells were detected using MTT assay and Western blotting, respectively. HCT116 and SW480 cells were treated with the AKT agonist SC79 or its inhibitor MK2206 for 24, 48, 72 and 96 h, and the changes in cell migration and invasion ability were analyzed using Transwell chamber assay and cell proliferation was assessed using MTT assay. The effects of SC79 and MK2206 on migration and invasion abilities of HCT116 and SW480 cells with or without ANP32A silencing were examined using wound healing and Transwell chamber assays, and the changes in the expression of metadherin (MTDH), a factor associated with cells invasion and migration, was detected with Western blotting. RESULTS: Lentivirus-mediated ANP32A silencing significantly down-regulated the activity of AKT and inhibited the proliferation of both HCT116 and SW480 cells (P < 0.01). The application of AKT inhibitor MK2206 obviously inhibited the proliferation, invasion and migration of the colorectal cancer cells (P < 0.05), while the AKT agonist SC79 significantly promoted the invasion and migration of the cells (P < 0.01). In HCT116 and SW480 cells with ANP32A silencing, treatment with MK2206 strongly enhanced the inhibitory effects of ANP32A silencing on cell invasion and migration (P < 0.05) and the expression of MTDH, while SC79 partially reversed these inhibitory effects (P < 0.01). CONCLUSION: ANP32A silencing inhibits invasion and migration of colorectal cancer cells possibly by inhibiting the activation of the AKT signaling pathway.

[Establishment and preliminary application of organoids in ovarian cancer].

Objective: To explore the establishment and application of ovarian cancer organoids. Methods: Fresh ovarian tumor tissues, obtaining from patients underwent surgery in the First Affiliated Hospital of Nanjing Medical University between October 2021 and March 2022, were collected, enzymatic degraded, digested, and embedded into matrigel to establish organoids. A total of 32 ovarian cancer samples were collected. Hematoxylin eosin (HE) staining and immunofluorescence (IF) procedure were used to verify the morphological structure of organoids and their expression of molecular markers. 3D cyto-live or dead assay was used to detecte the live or dead cells in organoids. Carboplatin with a concentration ranging from 5 to 80 µmol/L (5, 10, 20, 40, 80 µmol/L) was added to organoids to calculate the 50% inhibitory concentration (IC50) in different organoids. Results: (1) Organoids from a total of 32 patients were established, of which 18 cases could be passaged stably in the long term in vitro, while 14 could be passaged in the short time. The average amplification time of long-term passage in vitro was over 3 months, and the longest reached 9 months. (2) In HE staining, significant nuclei atypia and local micropapillary structures were observed in organoids. IF staining revealed that ovarian cancer organoids expressed molecular markers similar to primary tumor tissues, such as Pan cytokeratin (Pan-CK), p53, paired box gene 8 (PAX8), and Wilms tumor gene 1 (WT1). (3) In 3D cyto-live or dead assay, a large number of apoptotic cells were observed inside and around the organoids after added carboplatin. The sensitivity to carboplatin varied in 18 organoids could amplify in the long term, with an average IC50 of (29.5±15.8) µmol/L. Moreover, IC50 values of 4 organoids derived from patients received neoadjuvant chemotherapy were much higher than the 14 organoids which did not received neoadjuvant chemotherapy [(48.7±11.3) µmol/L vs (24.0±12.1) µmol/L; t=3.429, P=0.022]. Conclusions: Organoids recapitulate ovarian cancers in vitro and could be stably passaged. Organoids derived from patients received neoadjuvant chemotherapy have higher resistance to carboplatin.

[Healing of the dento-gingival junction following modified crown lengthening procedure in beagle dogs].

OBJECTIVE: To evaluate the type of wound healing following modified crown lengthening surgery in dog model to provide a biological basis for its clinical application. METHODS: Flap surgery, traditional crown lengthening procedure and modified crown lengthening procedure were performed on the right maxillary central incisor, the left maxillary central incisor and the left maxillary first lateral incisor respectively of five male beagle dogs. The right maxillary first lateral incisors with no surgical intervention were used as controls. Thirty-six weeks after the experimental procedure, tissue blocks were harvested and prepared for histological examination and analysis. RESULTS: Histometric examination of buccolingual sections stained with hematoxylin-eosin demonstrated that the type of wound healing in the flap surgery group was re-attachment, similar to the control group. For the traditional crown lengthening surgery group, all of the five beagle dogs had lamellar cementum defects on root surface, the wound healing of four beagle dogs was new attachment accompanied by new cementum formation at cementum defect areas and the suprac-restal connective tissue was functionally oriented perpendicular to the new cementum. The wound healing of the other beagle dog was long junctional epithelial attachment, in which the junctional epithelium extended to the apical terminus of the cementum defect. In the modified crown lengthening surgery group, four beagle dogs had cementum defects on root surface (two lamellar cementum defects and two shallow platform-like cementum defects), the wound healing of three beagle dogs was new attachment, however, the supracrestal connective tissue was parallel to the root surface. The type of wound healing of another one beagle dog was long junctional epithelial attachment. Wound healing of one beagle dog in this group could not be characterized due to incomplete dissection. CONCLUSION: Wound healing in the modified crown lengthening surgery group was similar to the traditional crown lengthening surgery group, and two types of wound healing were observed: new attachment and long junctional epithelium attachment. Neither type of root treatment procedure (root planing or root reshaping) nor root surface defect pattern (the lamellar cementum defect or shallow platform-like cementum defect) influenced the observed type of wound healing.

[The relationship between peripheral blood mitochondrial DNA copy number and incident risk of liver cancer: a case-cohort study].

Objective: To investigate the association between peripheral blood mitochondrial DNA copy number (mtDNAcn) and incident risk of liver cancer. Methods: At the baseline of Dongfeng-Tongji (DFTJ) cohort, 27 009 retirees were recruited from Dongfeng Motor Corporation in 2008. After excluding people without baseline DNA, with current malignant tumor and loss of follow-up, 1 173 participants were randomly selected into a sub-cohort by age-and gender-stratified sampling method at a proportion of 5% among all retirees. A total of 154 incident liver cancer cases identified from the cohort before December 31, 2018 (4 cases had been selected into the sub-cohort) were selected to form the case cohort of liver cancer. For the above 1 323 participants, their baseline levels of mtDNAcn in peripheral blood cells were measured by using quantitative real-time PCR method. The restricted cubic spline analysis was used to fit the shape of the association between baseline mtDNAcn and incident risk of liver cancer. The weighted Cox proportional hazards model was used to estimate the hazard ratio (HR) and 95%CI. Results: In this case-cohort study, the median follow-up time was 10.3 years. The restricted cubic spline analysis indicated that the relationship between peripheral blood mtDNAcn and incident risk of liver cancer followed a U-shaped pattern (Pnon-linear<0.05). All case-cohort population were divided into four subgroups by sex-specific quartiles of mtDNAcn levels among sub-cohort participants, when compared to participants in the Q2 subgroup of mtDNAcn, those in the Q1 subgroup (HR=2.00,95%CI:1.08-3.70) and Q4 subgroup (HR=4.11,95%CI:2.32-7.26) both had a significantly elevated risk of liver cancer, while those in the Q3 subgroup (HR=1.05,95%CI:0.54-2.05) had not. There were no significant multiply interaction effects of aging, gender, tobacco smoking, alcohol drinking and history of chronic hepatitis on the above association (Pinteraction>0.05). Conclusion: Both extremely low and high baseline level of mtDNAcn in peripheral blood cells are associated with an increased risk of incident liver cancer, but the underlying mechanisms need to be further clarified.

[Predictive value of prognostic inflammatory and tumor score in intrahepatic cholangiocarcinoma].

Objective: To compare and analyze the predictive value of different inflammatory factors and tumor markers in intrahepatic cholangiocarcinoma and to develop a new and effective preoperative prognostic scoring system. Methods: 102 and 72 cases with intrahepatic cholangiocarcinoma who underwent radical surgery in Tianjin Medical University Cancer Institute and Hospital and the Affiliated Hospital of Weifang Medical University were selected as the experimental group and the validation group, respectively. Clinicopathological and follow-up data were collected. Cox proportional-hazards model was used to analyze the predictive value of different prognostic markers. The relationship between prognostic markers and clinicopathological data was analyzed by rank sum test, χ2 or Fisher's exact test. Results: Among the direct inflammatory factors, tumor markers and combined inflammatory factors, prognostic inflammatory index (PII), carbohydrate antigen (CA) 19-9 and systemic inflammation score (SIS) were the most significant predictive factors for postoperative survival outcomes in patients with intrahepatic cholangiocarcinoma. The prognostic inflammatory and tumor score (PITS) was proposed as a new prognostic scoring system for intrahepatic cholangiocarcinoma. PII and CA19-9 were included into the scoring criteria for prognostic stratification of patients. PITS was an independent predictor of tumor-free survival and overall survival in patients with intrahepatic cholangiocarcinoma. Patients with high-grade PITS had later tumor grade and higher frequency of vascular invasion. Conclusion: PITS is highly effective prognostic scoring system for patients with intrahepatic cholangiocarcinoma. In addition, PITS is recommended for preoperative prognostic stratification in patients with intrahepatic cholangiocarcinoma.

Two-year outcomes of Roux-en-Y gastric bypass vs medical treatment in type 2 diabetes with a body mass index lower than 32.5 kg/m2: a multicenter propensity score-matched analysis.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) has been widely reported to be safe and feasible, and has a powerful effect on improving metabolism and weight loss in patients with a high body mass index (BMI). A few studies have focused on the comparison of RYGB with medical treatment in type 2 diabetes (T2D) patients with a lower BMI. OBJECTIVES: To compare the metabolic effects and safety of RYGB versus medical treatment during a 2 years follow-up in T2D patients with a BMI of 25 to 32.5 kg/m2. METHODS: This retrospective and multicenter cohort study participants were extracted from the T2D patients with a lower BMI (25-32.5 kg/m2) from three bariatric centers between 2009 and 2018. Propensity score matching (PSM) was used to minimize bias, and each patient in the surgical group was matched 1:2 to the patients in the medical group with the closest propensity score. Finally, 71 patients who received RYGB and 142 patients who underwent medical treatment with a 2 years follow-up were enrolled to compare the effects of RYGB and medical treatment. The primary endpoint was achievement of the triple endpoint (the simultaneous achievement of hemoglobin A1c (HbA1c) < 7.0%, fasting low-density lipoprotein cholesterol (LDL-C) < 100 mg/dL (2.6 mmol/L), and systolic blood pressure (SBP) < 130 mmHg at the year-1 visit). Changes in weight, BMI, medication usage, complications, and adverse events were assessed. RESULTS: In total, 213 patients (mean age of 47.4 ± 9.5 years, 70.4% male, mean BMI of 28.6 ± 2.2 kg/m2) were included in this study. At the end of the first year, 17 patients (23.9%) in the surgical group and 10 (7.0%) in the medical group had achieved the composite triple endpoint (OR 4.64; 95% CI 1.82-11.81; p = 0.001). Additionally, 43 patients (60.6%) in the surgical group and 11 patients (19.7%) in the medical group experienced remission of T2D. However, more complications were observed in the surgical group (36 vs. 22, p < 0.01). CONCLUSIONS: Among T2D patients with a BMI between 25.0 and 32.5 kg/m2, RYGB was more effective than medical treatment in resolving metabolic disorders and also resulted in more complications. The risk for complications should be considered in the clinical decision-making process for T2D patients with a low BMI.

[A cross-sectional study of periodontal pathogens in saliva of edentulous patients].

Objective: To investigate the prevalence of five specific periodontal pathogens in the saliva of edentulous patients and to compare the differences in the saliva of dentulous individuals with various periodontal conditions. Methods: All the subjects were patients who received regular care at the Beijing Hypertension Prevention and Management Institute. Twenty-seven edentulous patients (edentulous group) were included. According to age (age gap≤5 years), gender, smoking status, diabetes status and hypertension status, each edentulous patient was paired with dentulous individuals suffering from various severity of periodontitis in the same cohort. Then, we selected 3 groups of patients (n=27 in each group) with no or mild periodontitis (mild group), moderate periodontitis (moderate group) and severe periodontitis (severe group). The whole unstimulated saliva was collected before the periodontal examination. Questionnaire survey and periodontal parameters, including plaque index (PLI), probing depth (PD), bleeding index (BI) and clinical attachment loss (CAL), were examined at mesial-buccal and distal-lingual sites of each tooth respectively. DNA was extracted from each sample of the salivary deposition. Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Campylobacter rectus (Cr) and Prevotella nigrescens (Pn) were detected by using PCR method based on 16SrRNA. The prevalence and quantity of the pathogens under various severity of periodontitis were compared. Results: One or more periodontal pathogens could be detected from the 78% (21/27) of the salivary samples in edentulous group. Thereinto, the prevalences of the five periodontal pathogens were ranked as (from high to low): Cr [56% (15/27)], Tf [44% (12/27)], Pn [26% (7/27)], Pg [22% (6/27)] and Td [11% (3/27)]. All five pathogens' prevalences and Pg, Tf, Td and Pn's quantities showed statistical differences among the four groups. The numbers of detected bacterial species in the mild, moderate and severe groups were significantly higher than that in the edentulous group (P<0.01). Furthermore, the prevalences of the red complex in three dentulous groups [96% (26/27) in each group] were significantly higher than the edentulous group [48% (13/27)] (P<0.05). The proportions of the red complex among all five pathogens (83%) in moderate and severe groups were significantly higher than that in the edentulous group (37%) (P<0.01). Conclusions: All five periodontal pathogens could be detected in most of the saliva samples from edentulous individuals. Nevertheless, the prevalence and quantity were lower than dentulous individuals.

[Clinical pathological features of 180 cases with primary esophageal malignant melanoma].

Objective: To investigate the clinical pathological and epidemiological characteristics of primary esophageal malignant melanoma (PMME). Methods: The clinical pathology data of 180 PMME patients in the esophageal cancer database of the key laboratory of esophageal cancer research in Henan Province from 1973 to 2016 were collected, of which 136 were male, aged (58.5±9.0) years, 44 were female, aged (56.7±12.2) years. Kaplan-Meier and Log rank test were used for survival analysis, Cox regression scale model was used for risk factor analysis. Results: The incidence of PMME is 0.036% (180/500, 000), mostly were male (about 3∶1 for men: female). The common sites of PMME were the lower part of the esophagus (48.9%, 85/174), followed by the middle section of the esophagus (46.0%, 80/174) and the upper part of the esophagus (5.2%, 9/174). No black particles were seen in the PMME cells of 3 patients under microscope, and strong positive expressions of Melan-A and HMB453 were observed in these 3 patients by immunohistochemical results. Of the 129 patients who had a routine preoperative esophageal biopsy, 69 were undiagnosed with PMME (53.5%). The medium survival time of the whole group was 7.9 months, and the survival rates of 1, 2, 3, 5 years were 25.0%, 7.9%, 6.6% and 1.3%, respectively. The univariate analysis showed that N, M, TNM phase and radiotherapy were related to the overall survival of patients (P<0.05). Multivariate analysis showed that TNM phase and radiotherapy were the independent risk factors for overall survival of patients (P<0.05). Conclusions: PMME is more common in men, the common site of the disease is the lower part of the esophagus. The preoperatively missed diagnosis rate of Chinese PMME is high. TNM phase and radiotherapy are the independent risk factors for overall survival of patients.

PAX5-induced upregulation of LINC01194 exerts oncogenic properties by regulating GOLPH3 expression via miR-486-5p in prostate cancer.

OBJECTIVE: Several studies have demonstrated that long non-coding RNA can act as crucial roles during the progression of various tumors, including prostate cancer (PCa). We aimed to determine lncRNA LINC01194(LINC01194) expression in prostate cancer (PCa) and examine its influence on tumor behaviors of PCa cells. PATIENTS AND METHODS: RT-PCR was performed to examine LINC01194 and PAX5's expression levels in PCa tissues and cell lines. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were performed to explore whether PAX5 could activate the transcription of LINC01194. Cell viability, migration and invasion were assessed by CCK-8, colony formation, transwell assay and Wound-healing assays. Bioinformatics and Dual-Luciferase assays were used to investigate the interaction between LINC01194 and miR-486-5p, as well as between miR-486-5p and GOLPH3. Western blot was applied for detecting the expressions of the related proteins. RESULTS: LINC01194 was highly expressed in PCa specimens and cell lines. PAX5 could bind directly to LINC01194 promoter region and activate its transcription. Functionally, the proliferation and metastasis of PCa cells were substantially impeded by LINC01194 silencing in vitro and in vivo. Mechanistically, LINC01194 promoted PCa progression by serving as a sponge of miR-486-5p to increase GOLPH3 expression. CONCLUSIONS: Our study identifies LINC01194 as a tumor promotor in PCa and implicates the LINC01194/miR-486-5p/GOLPH3 axis in the PCa progression.

[S100A8/A9 and periodontal inflammatory diseases].

Calprotectin S100A8/A9, a heterodimer composed of S100A8 and S100A9, is the main component of cytoplasmic proteins in neutrophils. It plays multiple roles in the immuno-inflammatory reactions intracellularly and extracellularly. Recent studies find that S100A8/A9 is closely related with the initiation and progression of periodontal inflammatory diseases. S100A8/A9 is expected to be a new biomarker for diagnosing periodontal inflammatory diseases, monitoring inflammatory activities in patients with periodontitis, evaluating the outcome of periodontal treatments and predicting the susceptibility of individual patient to periodontitis. In this literature review, we summarize the clinical research progress on the relation between S100A8/A9 and periodontal inflammatory diseases.

[Preliminary study on the expression and distribution of S100A8 and S100A9 in healthy and experimental periodontitis tissues].

Objective: To investigate the systemic expression profile of S100A8 and S100A9 in healthy and inflamed periodontal tissues. Methods: Experimental periodontitis models were established by ligations around the mandibular second molars of six beagle dogs for 12 weeks (ligation group). The mandibular second molars on the opposite side were kept clean (healthy control group). The expressions of S100A8 and S100A9 in healthy and inflamed periodontal tissues of six beagle dogs were examined by immunohistochemistry. The expressions of S100A8 and S100A9 in primary human gingival fibroblasts (hGF) from 3 subjects and human periodontal ligament cells (hPDLC) from 3 other subjects were detected by immunocytochemistry. Results: After the ligation for 12 weeks, the mean probing depth of ligation group [(3.86±0.14) mm] was significantly higher than that of healthy control group [(2.11±0.28) mm] (P<0.01). Results of immunohistochemistry analysis indicated that S100A8 and S100A9 could be expressed in gingival epithelial cells and might infiltrated neutrophils in the healthy periodontium. Except for the gingival epithelial cells and neutrophils, both proteins were induced and expressed in gingival fibroblasts, periodontal ligament cells, microvascular endothelial cells and bone marrow fibroblasts under inflammatory conditions. The distribution of S100A8 and S100A9 differed in the healthy oral gingival epithelium (OGE), which becomes consistent in inflamed OGE. Additionally, the expressions of S100A8 and S100A9 were confirmed in primary hGF and hPDLC. Conclusions: Periodontal inflammation might enlarge the expression scope of S100A8 and S100A9 and enrich multiple cells with expressions of S100A8 and S100A9.