Detection of newly synthesized RNA reveals transcriptional reprogramming during ZGA and a role of Obox3 in totipotency acquisition.

Zygotic genome activation (ZGA) after fertilization enables the maternal-to-zygotic transition. However, the global view of ZGA, particularly at initiation, is incompletely understood. Here, we develop a method to capture and sequence newly synthesized RNA in early mouse embryos, providing a view of transcriptional reprogramming during ZGA. Our data demonstrate that major ZGA gene activation begins earlier than previously thought. Furthermore, we identify a set of genes activated during minor ZGA, the promoters of which show enrichment of the Obox factor motif, and find that Obox3 or Obox5 overexpression in mouse embryonic stem cells activates ZGA genes. Notably, the expression of Obox factors is severely impaired in somatic cell nuclear transfer (SCNT) embryos, and restoration of Obox3 expression corrects the ZGA profile and greatly improves SCNT embryo development. Hence, our study reveals dynamic transcriptional reprogramming during ZGA and underscores the crucial role of Obox3 in facilitating totipotency acquisition.

YY1-dependent transcriptional regulation manifests at the morula stage.

YY1 plays multifaceted roles in various cell types. We recently reported that YY1 regulates nucleosome organization in early mouse embryos. However, despite the impaired nucleosome organization in the absence of YY1, the transcriptome was minimally affected in eight-cell embryos. We then hypothesized that YY1 might prepare a chromatin environment to regulate gene expression at later stages. To test this possibility, we performed a transcriptome analysis at the morula stage. We found that a substantial number of genes are aberrantly expressed in the absence of YY1. Furthermore, our analysis revealed that YY1 is required for the transcription of LINE-1 retrotransposons.

Accuracy of Force Generation and Preparatory Prefrontal Oxygenation in Ballistic Hand Power and Precision Grips.

It remains unclear whether accurate motor performance and cortical activation differ among grasping forms across several force levels. In the present study, a ballistic target force matching task (20%, 40%, 60%, and 80% of maximum voluntary force) with power grip, side pinch, and pulp pinch was utilized to explore the accuracy of the forces generated as well as the muscular activity of intrinsic and extrinsic hand muscles. By using near-infrared spectroscopy, we also examined bilateral dorsolateral prefrontal cortex (DLPFC) activation during the preparatory phase (initial 10 s) of the task. The accuracy of the power grip and pulp pinch was relatively higher than that of the side pinch, and the electromyographic activity of intrinsic hand muscles exhibited a similar trend for power grip and side pinch, while the opposite muscle recruitment pattern was observed for pulp pinch. The increment of DLPFC oxygenation across force levels differed among grasping forms, with greater activity at relatively higher levels in the power grip and side pinch, and at relatively lower levels in the pulp pinch. Taken together, the differential contribution of the DLPFC may be responsible for force generation depending on different grasping forms and force levels.

Toll-like receptor 9-positive plasmacytoid dendritic cells promote Th17 immune responses in oral lichen planus stimulated by epithelium-derived cathepsin K.

Oral lichen planus (OLP) is a chronic inflammatory disease associated with T cell infiltration. The crosstalk between oral epithelium and mucosal T cells was considered to be crucial in the pathogenesis of OLP. Here, we selectively extracted the normal epithelium (NE) and lesional epithelium (LE) of buccal mucosa specimens from three patients with OLP by laser capture microdissection due to identify the pathogenic factors. Cathepsin K (CTSK) was identified as one of common upregulated genes in the LE by DNA microarray. Immunohistochemically, CTSK was distinctly detected in and around the LE, while it was rarely seen in the NE. Recent studies showed that CTSK enhanced Toll-like receptor 9 (TLR9) signaling in antigen-presenting cells, leading to Th17 cell differentiation. TLR9 expression mainly co-localized with CD123+ plasmacytoid dendritic cells (pDCs). The number of RORγt-positive cells correlated with that of CTSK-positive cells in OLP tissues. CD123+ pDCs induced the production of Th17-related cytokines (IL-6, IL-23, and TGF-ß) upon stimulation with TLR9 agonist CpG DNA. Moreover, single cell RNA-sequencing analysis revealed that TLR9-positive pDCs enhanced in genes associated with Th17 cell differentiation in comparison with TLR9-negative pDCs. CTSK could induce Th17-related production of CD123+ pDCs via TLR9 signaling to promote the pathogenesis of OLP.

Molecular mechanisms underlying totipotency.

Numerous efforts to understand pluripotency in mammals, using pluripotent stem cells in culture, have enabled the generation of artificially induced pluripotent stem cells, which serve as a valuable source for regenerative medicine and the creation of disease models. In contrast to these tremendous successes in the pluripotency field in the past few decades, our understanding of totipotency, which is highlighted by its broader plasticity than pluripotency, is still limited. This is largely attributable to the scarcity of available materials and the lack of in vitro models. However, recent technological advances have unveiled molecular features that characterize totipotent cells. Single-cell or low-input sequencing technologies allow the dissection of pre- and post-fertilization developmental processes at the molecular level with high resolution. In this review, we describe some of the key findings in understanding totipotency and discuss how totipotency is acquired at the beginning of life.

Aberrant histone methylation in mouse early preimplantation embryos derived from round spermatid injection.

Round spermatid injection (ROSI) is the last resort and recourse for men with nonobstructive azoospermia to become biological fathers of their children. However, the ROSI-derived offspring rate is lower than intracytoplasmic sperm injection (ICSI) in mice (20% vs. 60%). This low success rate has hindered the spread of ROSI in ART (Assisted Reproductive Technology). However, the cause of the ROSI-zygote-derived low offspring rate is currently unknown. In the previous studies, we reported that H3K9me3 and H3K27me3 exhibited ectopic localizations in male pronuclei (mPN) of ROSI-zygotes, suggesting that the carried over histone to zygotes conveys epigenetic information. In this study, we analyzed other histone modifications to explore unknown abnormalities. H3K36me3 showed an increased methylation state compared to ICSI-derived embryos but not for H3K4me3. Abnormal H3K36me3 was corrected until 2-cell stage embryos, suggesting a long window of reprogramming ability in ROSI-embryos. Treatment with TSA of ROSI-zygotes, which was reported to be capable of correcting ectopic DNA methylation in ROSI-zygotes, caused abnormalities of H3K36me3 in male and female PN (fPN) of the zygotes. In contrast, round spermatid TSA treatment before ROSI, which was reported to improve the preimplantation development of ROSI-zygotes, showed beneficial effects without toxicity in fPN. Therefore, the results suggest that TSA has some negative effects, but overall, it is effective in the correction of epigenetic abnormalities in ROSI-zygotes. When attempting to correct epigenetic abnormalities, attention should be paid to epigenomes not only in male but also in female pronuclei.

Dynamic nucleosome remodeling mediated by YY1 underlies early mouse development.

Nucleosome positioning can alter the accessibility of DNA-binding proteins to their cognate DNA elements, and thus its precise control is essential for cell identity and function. Mammalian preimplantation embryos undergo temporal changes in gene expression and cell potency, suggesting the involvement of dynamic epigenetic control during this developmental phase. However, the dynamics of nucleosome organization during early development are poorly understood. In this study, using a low-input MNase-seq method, we show that nucleosome positioning is globally obscure in zygotes but becomes well defined during subsequent development. Down-regulation of the chromatin assembly in embryonic stem cells can partially reverse nucleosome organization into a zygote-like pattern, suggesting a possible link between the chromatin assembly pathway and fuzzy nucleosomes in zygotes. We also reveal that YY1, a zinc finger-containing transcription factor expressed upon zygotic genome activation, regulates the de novo formation of well-positioned nucleosome arrays at the regulatory elements through identifying YY1-binding sites in eight-cell embryos. The YY1-binding regions acquire H3K27ac enrichment around the eight-cell and morula stages, and YY1 depletion impairs the morula-to-blastocyst transition. Thus, our study delineates the remodeling of nucleosome organization and its underlying mechanism during early mouse development.

Cytotoxic CD8+ T cells may be drivers of tissue destruction in Sjögren's syndrome.

Sjögren's syndrome is a chronic autoimmune disorder whose pathogenesis is poorly understood and that lacks effective therapies. Detailed quantitative and spatial analyses of tissues affected by Sjögren's syndrome were undertaken, including the quantitation of the frequency of selected cell-cell interactions in the disease milieu. Quantitative analyses of CD4+ T cell subsets and of CD8+ T cells in the labial salivary glands from untreated patients with primary Sjögren's syndrome revealed that activated CD8+ cytotoxic T cells (CD8+CTLs) were the most prominent T cells in these infiltrates. An accumulation of apoptotic glandular epithelial cells, mainly ductal and acinar cells, was observed, consistent with the impaired salivary secretion often observed in patients with this disease. FasL expressing activated CD8+ T cells were seen to accumulate around Fas expressing apoptotic epithelial cells. Quantitative analyses of apoptotic cell types and of conjugates between cytotoxic T cells and epithelial cells undergoing apoptosis suggest that Sjögren's syndrome is primarily driven by CD8+CTL mediated execution of epithelial cells mainly represented by ductal and acinar cells.

Paternally inherited H3K27me3 affects chromatin accessibility in mouse embryos produced by round spermatid injection.

Round spermatid injection (ROSI) results in a lower birth rate than intracytoplasmic sperm injection, which has hampered its clinical application. Inefficient development of ROSI embryos has been attributed to epigenetic abnormalities. However, the chromatin-based mechanism that underpins the low birth rate in ROSI remains to be determined. Here, we show that a repressive histone mark, H3K27me3, persists from mouse round spermatids into zygotes in ROSI and that round spermatid-derived H3K27me3 is associated with less accessible chromatin and impaired gene expression in ROSI embryos. These loci are initially marked by H3K27me3 but undergo histone modification remodelling in spermiogenesis, resulting in reduced H3K27me3 in normal spermatozoa. Therefore, the absence of epigenetic remodelling, presumably mediated by histone turnover during spermiogenesis, leads to dysregulation of chromatin accessibility and transcription in ROSI embryos. Thus, our results unveil a molecular logic, in which chromatin states in round spermatids impinge on chromatin accessibility and transcription in ROSI embryos, highlighting the importance of epigenetic remodelling during spermiogenesis in successful reproduction.

Hypercapnia elicits differential vascular and blood flow responses in the cerebral circulation and active skeletal muscles in exercising humans.

The purpose of this study was to investigate the effects of a rise in arterial carbon dioxide pressure (PaCO2 ) on vascular and blood flow responses in the cerebral circulation and active skeletal muscles during dynamic exercise in humans. Thirteen healthy young adults (three women) participated in hypercapnia and normocapnia trials. In both trials, participants performed a two-legged dynamic knee extension exercise at a constant workload that increased heart rate to roughly 100 beats min-1 . In the hypercapnia trial, participants performed the exercise with spontaneous breathing while end-tidal carbon dioxide pressure (PET CO2 ), an index of PaCO2 , was held at 60 mmHg by inhaling hypercapnic gas (O2 : 20.3 ± 0.1%; CO2 : 6.0 ± 0.5%). In the normocapnia trial, minute ventilation during exercise was matched to the value in the hypercapnia trial by performing voluntary hyperventilation with PET CO2 clamped at baseline level (i.e., 40-45 mmHg) through inhalation of mildly hypercapnic gas (O2 : 20.6 ± 0.1%; CO2 : 2.7 ± 1.0%). Middle cerebral artery mean blood velocity and the cerebral vascular conductance index were higher in the hypercapnia trial than in the normocapnia trial. By contrast, vascular conductance in the exercising leg was lower in the hypercapnia trial than in the normocapnia trial. Blood flow to the exercising leg did not differ between the two trials. These results demonstrate that hypercapnia-induced vasomotion in active skeletal muscles is opposite to that in the cerebral circulation. These differential vascular responses may cause a preferential rise in cerebral blood flow.

CD163+ M2 Macrophages Promote Fibrosis in IgG4-Related Disease Via Toll-like Receptor 7/Interleukin-1 Receptor-Associated Kinase 4/NF-κB Signaling.

OBJECTIVE: IgG4-related disease (IgG4-RD) is a fibro-inflammatory condition that can affect multiple organs. We previously demonstrated that TLR7-transgenic C57BL/6 mice showed elevated serum IgG1 levels and inflammation with fibrosis in the salivary glands (SGs), lungs, and pancreas. Moreover, we observed extensive Toll-like receptor 7 (TLR-7)-positive CD163+ M2 macrophage infiltration in SGs from IgG4-RD patients. We undertook this study to examine the fibrotic mechanism via the TLR-7 pathway. METHODS: Gene expression in SGs from human TLR7-transgenic mice and IgG4-RD patients was analyzed using DNA microarrays. We extracted the common up-regulated TLR-7-related genes in SGs from TLR7-transgenic mice and IgG4-RD patients. Finally, we investigated the interaction between CD163+ M2 macrophages and fibroblasts before and after stimulation with the TLR-7 agonist loxoribine. RESULTS: In TLR7-transgenic mice and IgG4-RD patients, IRAK3 and IRAK4 were significantly overexpressed. Real-time polymerase chain reaction validated the up-regulation of only IRAK4 in IgG4-RD patients compared with the other groups (P < 0.05). Interleukin-1 receptor-associated kinase 4 (IRAK4) was strongly detected in and around germinal centers in SGs from patients with IgG4-related dacryoadenitis and sialadenitis alone. Double immunofluorescence staining showed that IRAK4-positive cells were mainly colocalized with CD163+ M2 macrophages in SGs (P < 0.05). After stimulation with loxoribine, CD163+ M2 macrophages exhibited significantly enhanced expression of IRAK4 and NF-κB and increased supernatant concentrations of fibrotic cytokines. Finally, we confirmed that the number of fibroblasts was increased by culture with the supernatant of CD163+ M2 macrophages following stimulation with loxoribine (P < 0.05). CONCLUSION: CD163+ M2 macrophages promote fibrosis in IgG4-RD by increasing the production of fibrotic cytokines via TLR-7/IRAK4/NF-κB signaling.

Simulation study on radiation exposure of emergency medical responders from radioactively contaminated patients.

Emergency medical responders (EMRs) who treat victims during a radiation emergency are at risk of radiation exposure. In this study, the exposure dose to EMRs treating hypothetically contaminated patients was estimated using a Monte Carlo simulation, and the findings may be useful for educating EMRs and reducing their anxiety. The Monte Carlo simulation estimated radiation doses for adult computational phantoms based on radioactive contamination conditions and radiation dosages from previous studies. At contamination conditions below the typical upper limit of general Geiger-Müller survey meters, the radiation doses to EMRs were estimated to be less than 1 µSv per hour. In cases with greater contamination due to mishandling of an intense radioactive source (hundreds of GBq), the radiation doses to EMRs could reach approximately 100 mSv per hour. These results imply that a radiological accident with a highly radioactive source could expose EMR to significant radiation that exceeds their dose limit. Thus, authorities and other parties should ensure that EMRs receive appropriate education and training regarding measures that can be taken to protect themselves from the possibility of excessive radiation exposure. The results of this study may provide EMRs with information to take appropriate protective measures, although it is also important that they not hesitate to perform lifesaving measures because of concerns regarding radiation.

CD4+ and CD8+ cytotoxic T lymphocytes may induce mesenchymal cell apoptosis in IgG4-related disease.

BACKGROUND: IgG4-related disease (IgG4-RD) is an immune-mediated fibrotic disorder that has been linked to CD4+ cytotoxic T lymphocytes (CD4+CTLs). The effector phenotype of CD4+CTLs and the relevance of both CD8+ cytotoxic T lymphocytes (CD8+CTLs) and apoptotic cell death remain undefined in IgG4-RD. OBJECTIVE: We sought to define CD4+CTL heterogeneity, characterize the CD8+CTL response in the blood and in lesions, and determine whether enhanced apoptosis may contribute to the pathogenesis of IgG4-RD. METHODS: Blood analyses were undertaken using flow cytometry, cell sorting, transcriptomic analyses at the population and single-cell levels, and next-generation sequencing for the TCR repertoire. Tissues were interrogated using multicolor immunofluorescence. Results were correlated with clinical data. RESULTS: We establish that among circulating CD4+CTLs in IgG4-RD, CD27loCD28loCD57hi cells are the dominant effector subset, exhibit marked clonal expansion, and differentially express genes relevant to cytotoxicity, activation, and enhanced metabolism. We also observed prominent infiltration of granzyme A-expressing CD8+CTLs in disease tissues and clonal expansion in the blood of effector/memory CD8+ T cells with an activated and cytotoxic phenotype. Tissue studies revealed an abundance of cells undergoing apoptotic cell death disproportionately involving nonimmune, nonendothelial cells of mesenchymal origin. Apoptotic cells showed significant upregulation of HLA-DR. CONCLUSIONS: CD4+CTLs and CD8+CTLs may induce apoptotic cell death in tissues of patients with IgG4-RD with preferential targeting of nonendothelial, nonimmune cells of mesenchymal origin.

A Simple Survey of the Preparation Situation for Resident's Evacuation in Japanese Prefectures After the Fukushima Daiichi Nuclear Power Plant Accident.

The Japanese government formulated the Nuclear Emergency Response Guidelines in response to the Fukushima Daiichi Nuclear Power Plant accident (FDNPP accident) caused by the Great East Japan Earthquake in March 2011. Under these guidelines, Japan has established its current nuclear disaster response system. This manuscript outlines the transition of Japan's nuclear disaster response system before and after the FDNPP accident and also shows the results of a questionnaire survey on the level of preparation the prefecture currently has for the evacuation of residents at the time of a nuclear disaster. About 70% of the prefectures where nuclear facilities are located or adjacent have completed or are in the process of completing evacuation plans, and all except one indicated they have the equipment needed to perform radiation contamination inspections of residents. These results suggest that activities are taking place throughout Japan to build a new disaster response system. It will be important to verify whether the evacuation manuals prepared by prefectural governments are effective through large-scale training and to develop human resources for performing radiation contamination inspections of evacuating residents.

The diagnostic utility of submandibular gland sonography and labial salivary gland biopsy in IgG4-related dacryoadenitis and sialadenitis: Its potential application to the diagnostic criteria.

Objectives: In this study, we investigated the diagnostic utility of submandibular gland (SMG) sonography and labial salivary gland (LSG) biopsy as a less invasive procedure for diagnosing IgG4-related dacryoadenitis and sialadenitis (IgG4-DS)Methods: Sixty-eight patients with suspected IgG4-DS by presenting swelling of elevated serum IgG (>1747 mg/dl) and/or swelling glands underwent SMG sonography, LSG biopsy and measurement for serum IgG4. SMG sonographic diagnosis was determined by the following characteristic changes; 'hypoechoic areas of a nodal pattern with high vascularity' and/or 'hypoechoic areas of a reticular pattern in the superficial part'.Results: Thirty-one patients were diagnosed with IgG4-DS, 5 with IgG4-RD unaccompanied by lacrimal and salivary gland lesions, 28 with Sjögren's syndrome, and 4 with malignant lymphoma. The sensitivity, specificity, and accuracy of SMG sonography and LSG biopsy were 100%, 83.8%, 91.2% and 64.5%, 73.8%, 75.0%, respectively. Moreover, those of SMG sonography and LSG biopsy combined with serum IgG4 concentration (>135 mg/dl) were 100%, 94.6%, 97.1% and 64.5%, 91.9%, 79.4%, respectively.Conclusion: LSG biopsy needs to be extremely careful to diagnose IgG4-DS because of its low sensitivity. SMG sonography is sufficient for the diagnosis of IgG4-DS, especially when combined with serologic analysis. Thus, SMG sonography could adapt to the diagnostic criteria of IgG4-DS as a non-invasive method.

Activated M2 Macrophages Contribute to the Pathogenesis of IgG4-Related Disease via Toll-like Receptor 7/Interleukin-33 Signaling.

OBJECTIVE: IgG4-related disease (IgG4-RD) is a unique inflammatory disorder in which Th2 cytokines promote IgG4 production. In addition, recent studies have implicated the Toll-like receptor (TLR) pathway. This study was undertaken to examine the expression of TLRs in salivary glands (SGs) from patients with IgG4-RD. METHODS: SGs from 15 patients with IgG4-RD, 15 patients with Sjögren's syndrome (SS), 10 patients with chronic sialadenitis, and 10 healthy controls were examined histologically. TLR family gene expression (TLR-1 through TLR-10) was analyzed by DNA microarray in the submandibular glands (SMGs). Up-regulation of TLRs was confirmed in SGs from patients with IgG4-RD. Finally, the phenotype of human TLR-7 (huTLR-7)-transgenic C57BL/6 mice was assessed before and after stimulation with TLR agonist. RESULTS: In patients with IgG4-RD, TLR-4, TLR-7, TLR-8, and TLR-9 were overexpressed. Polymerase chain reaction validated the up-regulation of TLR-7 in IgG4-RD compared with the other groups. Immunohistochemical analysis confirmed strong infiltration of TLR-7-positive cells in the SGs of patients with IgG4-RD. Double immunohistochemical staining showed that TLR-7 expression colocalized with CD163+ M2 macrophages. After in vitro stimulation with a TLR-7 agonist, CD163+ M2 macrophages produced higher levels of interleukin-33 (IL-33), which is a Th2-activating cytokine. In huTLR-7-transgenic mice, the focus and fibrosis scores in SMGs, pancreas, and lungs were significantly higher than those in wild-type mice (P < 0.05). Moreover, the concentration of serum IgG, IgG1, and IL-33 in huTLR-7-transgenic mice was distinctly increased upon stimulation with a TLR-7 agonist (P < 0.05). CONCLUSION: TLR-7-expressing M2 macrophages may promote the activation of Th2 immune responses via IL-33 secretion in IgG4-RD.

CD206+ tumor-associated macrophages promote proliferation and invasion in oral squamous cell carcinoma via EGF production.

Tumor-associated macrophages (TAMs) promote tumor progression and inhibit anti-tumor immune response by producing various mediators and preferentially express CD163, CD204, and CD206. However, the role of these TAM subsets in oral squamous cell carcinoma (OSCC) remains unclear. Here we investigated the expression and function of TAM subsets in OSCC, especially in cancer cell proliferation. Biopsy sample from 44 patients with OSCC were examined for the expression of TAM markers and EGF by immunohistochemistry. EGF production of TAM subsets isolated from OSCC patients was assessed by flow cytometry. We also examined the effect of conditioned medium from TAM subsets on the proliferation of OSCC cells. CD163+ cells were detected diffusely all over the tumor and connective tissue area, while CD204+ and CD206+ cells were mainly detected in/around the tumors. Flow cytometric analysis found that CD206+ TAMs strongly produced EGF compared with CD163+ and CD204+ TAMs. Cell proliferation and invasion of OSCC cells cultured with conditioned medium of CD206+ TAMs were strongly enhanced and inhibited by anti-EGFR. The number of CD206+ TAMs positively correlated with worse clinical prognosis. Our results revealed differences in localization and EGF production among these TAM subsets. CD206+ TAMs might play a critical role in the proliferation of OSCC via EGF production.

Intestinal Epithelial Cell-specific Deletion of α-Mannosidase II Ameliorates Experimental Colitis.

Inflammatory bowel disease (IBD) is a refractory disease of the gastrointestinal tract that is believed to develop in genetically susceptible individuals. Glycosylation, a type of post-translational modification, is involved in the development of a wide range of diseases, including IBD, by modulating the function of various glycoproteins. To identify novel genes contributing to the development of IBD, we analyzed single nucleotide polymorphisms (SNPs) of glycosylation-related genes in IBD patients and identified MAN2A1, encoding alpha-mannosidase II (α-MII), as a candidate gene. α-MII plays a crucial, but not exclusive, role in the maturation of N-glycans. We also observed that intestinal epithelial cells (IECs), which establish the first-line barrier and regulate gut immunity, selectively expressed α-MII with minimal expression of its isozyme, alpha-mannosidase IIx (α-MIIx). This led us to hypothesize that IEC-intrinsic α-MII is implicated in the pathogenesis of IBD. To test this hypothesis, we generated IEC-specific α-MII-deficient (α-MIIΔIEC) mice. Although α-MII deficiency has been shown to have a minimal effect on N-glycan maturation in most cell types due to the compensation by α-MIIx, ablation of α-MII impaired the maturation of N-glycans in IECs. α-MIIΔIEC mice were less susceptible to dextran sulfate sodium-induced colitis compared with control littermates. In accordance with this, neutrophil infiltration in the colonic mucosa was attenuated in α-MIIΔIEC mice. Furthermore, gene expression levels of neutrophil-attracting chemokines were downregulated in the colonic tissue. These results suggest that IEC-intrinsic α-MII promotes intestinal inflammation by facilitating chemokine expression. We propose SNPs in MAN2A1 as a novel genetic factor for IBD.Key words: inflammatory bowel disease, alpha-mannosidase II, intestinal epithelial cell, N-glycosylation.

CD163+CD204+ tumor-associated macrophages contribute to T cell regulation via interleukin-10 and PD-L1 production in oral squamous cell carcinoma.

Tumor-associated macrophages (TAMs) promote cancer cell proliferation, invasion, and metastasis by producing various mediators. Although preclinical studies demonstrated that TAMs preferentially express CD163 and CD204, the TAM subsets in oral squamous cell carcinoma (OSCC) remain unknown. In this study, we examined the expression and role of TAM subsets in OSCC. Forty-six patients with OSCC were analyzed for expression of TAMs in biopsy samples by immunohistochemistry. We examined TAM subsets and their production of immune suppressive molecules (IL-10 and PD-L1) in peripheral blood mononuclear cells from three OSCC patients by flow cytometry. CD163 was detected around the tumor or connective tissue, while CD204 was detected in/around the tumors. Flow cytometric analysis revealed that CD163+CD204+ TAMs strongly produced IL-10 and PD-L1 in comparison with CD163+CD204- and CD163-CD204+ TAMs. Furthermore, the number of activated CD3+ T cells after co-culture with CD163+CD204+ TAMs was significantly lower than that after co-culture with other TAM subsets. In clinical findings, the number of CD163+CD204+ TAMs was negatively correlated with that of CD25+ cells and 5-year progression-free survival. These results suggest that CD163+CD204+ TAMs possibly play a key role in the invasion and metastasis of OSCC by T-cell regulation via IL-10 and PD-L1 production.

Myeloid dendritic cells stimulated by thymic stromal lymphopoietin promote Th2 immune responses and the pathogenesis of oral lichen planus.

Oral lichen planus (OLP) is a chronic inflammatory disease characterized by subepithelial T-cell infiltration. Recent studies reported that specific T helper (Th) subsets, especially Th2 cells, are involved in the pathogenesis of OLP. Thymic stromal lymphopoietin (TSLP) is mainly secreted by epithelial cells and potently activates myeloid dendritic cells (mDCs) to induce Th2-mediated inflammation. Here, we investigated the expression of TSLP and related molecules in OLP. Buccal mucosa specimens from patients with OLP, hyperkeratosis, and ulcer were analyzed by immunohistochemistry for expression of TSLP, its receptor (TSLPR), and inflammatory cells. TSLP was detected in/around the epithelium of patients with OLP and hyperkeratosis, whereas TSLPR, CD11c (mDC), and GATA3 (Th2) were strongly expressed in the subepithelial layer only in OLP patients. Double immunofluorescence staining showed that TSLPR expression mainly co-localized with CD11c. Moreover, the number of CD11c- and GATA-3 positive cells was correlated in OLP patients. In lesions selectively extracted by laser microdissection, the mRNA expression of Th2 (IL-4, MDC, TARC, GATA3)- and Th17 (IL-17, RORγt)-related molecules in OLP patients was significantly higher than in other groups. These results suggest that CD11c+ mDCs expressing TSLPR contribute to aberrant Th2 immune responses and the pathogenesis of OLP via TSLP stimulation.