Defective Reelin/Dab1 signaling pathways associated with disturbed hippocampus development of homozygous yotari mice.

Homozygous Dab1 yotari mutant mice, Dab1yot (yot/yot) mice, have an autosomal recessive mutation of Dab1 and show reeler-like phenotype including histological abnormality of the cerebellum, hippocampus, and cerebral cortex. We here show abnormal hippocampal development of yot/yot mice where granule cells and pyramidal cells fail to form orderly rows but are dispersed diffusely in vague multiplicative layers. Possibly due to the positioning failure of granule cells and pyramidal cells and insufficient synaptogenesis, axons of the granule cells did not extend purposefully to connect with neighboring regions in yot/yot mice. We found that both hippocampal granule cells and pyramidal cells of yot/yot mice expressed proteins reactive with the anti-Dab1 antibody. We found that Y198- phosphorylated Dab1 of yot/yot mice was greatly decreased. Accordingly the downstream molecule, Akt was hardly phosphorylated. Especially, synapse formation was defective and the distribution of neurons was scattered in hippocampus of yot/yot mice. Some of neural cell adhesion molecules and hippocampus associated transcription factors of the neurons were expressed aberrantly, suggesting that the Reelin-Dab1 signaling pathway seemed to be importantly involved in not only neural migration as having been shown previously but also neural maturation and/or synaptogenesis of the mice. It is interesting to clarify whether the defective neural maturation is a direct consequence of the dysfunctional Dab1, or alternatively secondarily due to the Reelin-Dab1 intracellular signaling pathways.

Serum-Induced Expression of Brain Natriuretic Peptide Contributes to Its Increase in Patients with HFpEF.

Brain natriuretic peptide (BNP) levels are increased in both patients with heart failure with preserved (HFpEF) and reduced ejection fraction (HFrEF), but the reasons for this remain unclear. Our purpose was to examine whether serum-induced BNP (iBNP) expression partly contributes to increased BNP in patients with HFpEF. BNP reporter cardiomyocytes from pBNP-luc-KI mice were stimulated with serum from patients with HFpEF or HFrEF (n = 114 and n = 82, respectively). Luciferase activity was examined as iBNP and the iBNP-to-BNP ratio was evaluated. Patient characteristics and clinical parameters were compared, and multivariate regression analysis was performed to determine independent predictors of the iBNP-to-BNP ratio. Female sex and frequencies of atrial fibrillation, hypertension and the use of a calcium channel blocker (CCB) were higher in HFpEF. The iBNP-to-BNP ratio was significantly higher in HFpEF (26.9) than in HFrEF (16.1, p < 0.001). Multivariate regression analysis identified the existence of HFpEF as an independent predictor of the iBNP-to-BNP ratio after adjusting for all other measurements (ß = 0.154, p = 0.032). Age, hemoglobin, CCB usage and deceleration time were also independent predictors (ß = 0.167, p = 0.025; ß = 0.203, p = 0.006; ß = 0.138, p = 0.049; and ß = 0.143, p = 0.049, respectively). These results indicate that the elevated BNP in patients with HFpEF is partly due to iBNP from the heart.

Interaction between SDF1 and CXCR4 Promotes Photoreceptor Differentiation via Upregulation of NFκB Pathway Signaling Activity in Pax6 Gene-Transfected Photoreceptor Precursors.

BACKGROUND: CCL2 (also known as monocyte chemoattractant protein 1) and CX3CR1 (also known as Fractalkine receptor)-deficient mice have damaged photoreceptors. OBJECTIVES: We examined the interaction of SDF1 and CXCR4 on the differentiation of retinal progenitors into rhodopsin-positive photoreceptors. METHODS: Cloned retinal progenitors were obtained by Pax6 gene transfection of mouse iPS cells followed by serial dilution. Clones were selected by expression of nestin, Musashi1, Six3, and Chx10 mRNA. Cell surface protein expression was analyzed by flow cytometry. The levels of mRNA and intracellular protein were examined by real-time PCR and immunochemistry, respectively. Transient transfection experiments of retinal progenitors were conducted using a human rhodopsin promoter luciferase plasmid. RESULTS: We selected 10 clones that expressed Six3, Chx10, Crx, Rx1, Nrl, CD73, and rhodopsin mRNA, which, except for rhodopsin, are photoreceptor precursor markers. Clones expressed both CD73 and CXCR4 on the cell surface and differentiated into rhodopsin-positive photoreceptors, which was reinforced by the addition of exogenous SDF1. A CXCR4 inhibitor AMD3100 blocked SDF1-mediated differentiation of progenitors into photoreceptors. SDF1 enhanced human rhodopsin promoter transcription activity, possibly via the NFκB pathway. Addition of SDF1 to the cell culture induced nuclear translocation of NFκB on retinal progenitor cell clones. Neonatal and newborn mouse retinas expressed SDF1 and CXCR4. Cells in the outer nuclear layer where photoreceptors are located expressed CXCR4 at P14 and P56. Cells in the inner nuclear layer expressed SDF1. CONCLUSIONS: These findings suggest that retinal progenitor cell differentiation was at least partly regulated by SDF1 and CXCR4 via upregulation of NFκB activity.

Precise Regulation of the Basal PKCγ Activity by DGKγ Is Crucial for Motor Coordination.

Diacylglycerol kinase γ (DGKγ) is a lipid kinase to convert diacylglycerol (DG) to phosphatidic acid (PA) and indirectly regulates protein kinase C γ (PKCγ) activity. We previously reported that the basal PKCγ upregulation impairs cerebellar long-term depression (LTD) in the conventional DGKγ knockout (KO) mice. However, the precise mechanism in impaired cerebellar LTD by upregulated PKCγ has not been clearly understood. Therefore, we first produced Purkinje cell-specific DGKγ KO (tm1d) mice to investigate the specific function of DGKγ in Purkinje cells and confirmed that tm1d mice showed cerebellar motor dysfunction in the rotarod and beam tests, and the basal PKCγ upregulation but not PKCα in the cerebellum of tm1d mice. Then, the LTD-induced chemical stimulation, K-glu (50 mM KCl + 100 µM, did not induce phosphorylation of PKCα and dissociation of GluR2 and glutamate receptor interacting protein (GRIP) in the acute cerebellar slices of tm1d mice. Furthermore, treatment with the PKCγ inhibitor, scutellarin, rescued cerebellar LTD, with the phosphorylation of PKCα and the dissociation of GluR2 and GRIP. In addition, nonselective transient receptor potential cation channel type 3 (TRPC3) was negatively regulated by upregulated PKCγ. These results demonstrated that DGKγ contributes to cerebellar LTD by regulation of the basal PKCγ activity.

BNP as a Major Player in the Heart-Kidney Connection.

Brain natriuretic peptide (BNP) is an important biomarker for patients with heart failure, hypertension and cardiac hypertrophy. Although it is known that BNP levels are relatively higher in patients with chronic kidney disease and no heart disease, the mechanism remains unknown. Here, we review the functions and the roles of BNP in the heart-kidney interaction. In addition, we discuss the relevant molecular mechanisms that suggest BNP is protective against chronic kidney diseases and heart failure, especially in terms of the counterparts of the renin-angiotensin-aldosterone system (RAAS). The renal medulla has been reported to express depressor substances. The extract of the papillary tips from kidneys may induce the expression and secretion of BNP from cardiomyocytes. A better understanding of these processes will help accelerate pharmacological treatments for heart-kidney disease.

CTLA4 blockade elicits paraneoplastic neurological disease in a mouse model.

CTLA4 is an inhibitory regulator of immune responses. Therapeutic CTLA4 blockade enhances T cell responses against cancer and provides striking clinical results against advanced melanoma. However, this therapy is associated with immune-related adverse events. Paraneoplastic neurologic disorders are immune-mediated neurological diseases that develop in the setting of malignancy. The target onconeural antigens are expressed physiologically by neurons, and aberrantly by certain tumour cells. These tumour-associated antigens can be presented to T cells, generating an antigen-specific immune response that leads to autoimmunity within the nervous system. To investigate the risk to develop paraneoplastic neurologic disorder after CTLA4 blockade, we generated a mouse model of paraneoplastic neurologic disorder that expresses a neo -self antigen both in Purkinje neurons and in implanted breast tumour cells. Immune checkpoint therapy with anti-CTLA4 monoclonal antibody in this mouse model elicited antigen-specific T cell migration into the cerebellum, and significant neuroinflammation and paraneoplastic neurologic disorder developed only after anti-CTLA4 monoclonal antibody treatment. Moreover, our data strongly suggest that CD8 + T cells play a final effector role by killing the Purkinje neurons. Taken together, we recommend heightened caution when using CTLA4 blockade in patients with gynaecological cancers, or malignancies of neuroectodermal origin, such as small cell lung cancer, as such treatment may promote paraneoplastic neurologic disorders.

Treatment of high-latency microcapsules containing an aluminium complex with an epoxy-functionalised trialkoxysilane.

Some aluminium complexes are excellent catalysts of cationic polymerisation and are used for low-temperature and fast-curing adhesive, used in electronic part mounting. Microencapsulation is a suitable technique for getting high latency of the catalysts and long shelf life of the adhesives. For the higher latency in a cycloaliphatic epoxy compound, the microcapsule surface which retained small amount of aluminium complex was coated with epoxy polymer and the effect was examined. From the X-ray photoelectron spectroscopic results, the surface was recognised to be sufficiently coated and the differential scanning calorimetric analyses showed that the coating did not significantly affect the low-temperature and fast-curing properties of adhesive. After storing the mixture of cycloaliphatic epoxy compound, coated microcapsules, triphenylsilanol and silane coupling agent for 48 h at room temperature, the increase in viscosity was only 0.01 Pa s, resulting in the excellent shelf life.

K-rasG12V mediated lung tumor models identified three new quantitative trait loci modifying events post-K-ras mutation.

A high incidence of oncogenic K-ras mutations is observed in lung adenocarcinoma of human cases and carcinogen-induced animal models. The process of oncogenic K-ras-mediated lung adenocarcinogenesis can be dissected into two parts: pre- and post-K-ras mutation. Adoption of transgenic lines containing a flox-K-rasG12V transgene eliminates the use of chemical carcinogens and enables us to study directly crucial events post-K-ras mutation without considering the cellular events involved with oncogenic K-ras mutation, e.g., distribution and metabolism of chemical carcinogens, DNA repair, and somatic recombination by host factors. We generated two mouse strains C57BL/6J-Ryr2(tm1Nobs) and A/J-Ryr2(tm1Nobs) in which K-rasG12V can be transcribed from the cytomegalovirus early enhancer/chicken beta actin promoter in virtually any tissue. Upon K-rasG12V induction in lung epithelial cells by an adenovirus expressing the Cre recombinase, the number of tumors in the C57BL/6J-Ryr2(tm1Nobs/+) mouse line was 12.5 times that in the A/J-Ryr2(tm1Nobs/+) mouse line. Quantitative trait locus (QTL) analysis revealed that new three modifier loci, D3Mit19, D3Mit45 and D11Mit20, were involved in the differential susceptibility between the two lines. In addition, we found that differential expression of the wild-type K-ras gene, which was genetically turn out to be anti-oncogenic activity on K-rasG12V, could not account for the different susceptibility in our two K-rasG12V-mediated lung tumor models. Thus, we provide a genetic system that enables us to explore new downstream modifiers post-K-ras mutation.

Development of axon-target specificity of ponto-cerebellar afferents.

The function of neuronal networks relies on selective assembly of synaptic connections during development. We examined how synaptic specificity emerges in the pontocerebellar projection. Analysis of axon-target interactions with correlated light-electron microscopy revealed that developing pontine mossy fibers elaborate extensive cell-cell contacts and synaptic connections with Purkinje cells, an inappropriate target. Subsequently, mossy fiber-Purkinje cell connections are eliminated resulting in granule cell-specific mossy fiber connectivity as observed in mature cerebellar circuits. Formation of mossy fiber-Purkinje cell contacts is negatively regulated by Purkinje cell-derived BMP4. BMP4 limits mossy fiber growth in vitro and Purkinje cell-specific ablation of BMP4 in mice results in exuberant mossy fiber-Purkinje cell interactions. These findings demonstrate that synaptic specificity in the pontocerebellar projection is achieved through a stepwise mechanism that entails transient innervation of Purkinje cells, followed by synapse elimination. Moreover, this work establishes BMP4 as a retrograde signal that regulates the axon-target interactions during development.

Protein profiles of peripheral blood mononuclear cells as a candidate biomarker for Behçet's disease.

OBJECTIVES: To investigate the pathophysiology of Behçet's disease (BD) and find biomarkers for the disease, we analysed protein profiles of peripheral blood mononuclear cells (PBMCs). METHODS: Proteins, extracted from PBMCs, were comprehensively analysed in 16 patients with BD, 16 patients with rheumatoid arthritis (RA), 12 patients with Crohn's disease (CD), and 16 healthy control subjects (HC) by 2-dimensional differential gel electrophoResis (2D-DIGE). Differently expressed proteins were identified by mass spectrometry. RESULTS: 563 protein spots were detected. We completely discriminated between the BD and HC groups, between the BD and RA groups, and between the BD and CD groups by multivariate analysis of intensity of 23, 35, and 1 spots, respectively. The spots contributing to the differences included proteins related to cytoskeleton, transcription/translation, T cell activation, bone turnover, regulating apoptosis, and microbial infection. Intensity of 3 spots (tyrosine-protein phosphatase non-receptor type 4, threonine synthase-like 2, and ß-actin) provided area under the receiver operating characteristic curves (AUROC) of 0.889 for discrimination between the BD group and the non-BD groups. Informatively, intensity of the above 1 spot completely discriminated the CD group from the other groups (AUROC 1.000). This spot, identified as ß-actin, had different pI from the above ß-actin-spot probably due to different post-translational modification. CONCLUSIONS: PBMC protein profiles, especially the profile of the 3 spots, would be candidate biomarkers for BD. The latter ß-actin subtype would be useful for discriminating inflammatory bowel diseases from BD and other diseases. The identified proteins may play important roles in the pathophysiology of BD.

Therapeutic effect of intratumoral injections of dendritic cells for locally recurrent gastric cancer: a case report.

An 80-year-old man with a history of gastric cancer and pulmonary emphysema underwent a distal gastrectomy for gastric cancer in 1997. In 2010, an endoscopic examination revealed a depressed-type lesion at the oral side of the anastomosis, which was diagnosed as signet-ring adenocarcinoma. Surgical management was considered, but was rejected because of obstructive and restrictive respiratory events. Chemotherapy was terminated because of adverse events. Endoscopy was used to administer intratumoral injections of dendritic cells (DCs) targeting synthesized peptides of Wilms tumor 1 (WT1) and mucin 1, cell-surface associated (MUC1). An immunohistochemical analysis of the tumor samples indicated positivity for WT1 and MUC1. One month after seven cycles of DC had been administered (between November 2010 and April 2011), no suspicious lesions were evident, and his biopsy results were normal. The patient has been in remission for 30 months. Intratumoral injections of DCs showed therapeutic effects in this patient, who could not undergo endoscopic submucosal dissection or surgery.

Serum level of soluble triggering receptor expressed on myeloid cells-1 as a biomarker of disease activity in relapsing polychondritis.

OBJECTIVES: We aimed to identify a serum biomarker for evaluating the disease activity of relapsing polychondritis (RP). METHODS: We measured and compared serum levels of 28 biomarkers potentially associated with this disease, including soluble triggering receptor expressed on myeloid cells-1 (sTREM-1), high-sensitivity C-reactive protein (hs-CRP), and cartilage oligomeric matrix protein (COMP), in 15 RP patients and 16 healthy donors (HDs). We divided the 15 RP patients into active RP (n = 8) and inactive RP (n = 7) groups, depending on the extent of the disease, and compared candidate markers between groups. The localization of membrane-bound TREM-1 in the affected tissue was examined by immunohistochemistry. RESULTS: Serum levels of sTREM-1, interferon-γ, chemokine (C-C motif) ligand 4, vascular endothelial growth factor, and matrix metalloproteinases-3 were significantly higher in RP patients than HDs. Among these markers, sTREM-1 had the highest sensitivity and specificity (86.7 and 86.7 %, respectively). Furthermore, the serum level of sTREM-1 was significantly higher in active RP patients than inactive RP patients (p = 0.0403), but this was not true for hs-CRP or COMP. TREM-1 was expressed on endothelial cells in RP lesions. CONCLUSIONS: The serum level of sTREM-1 may be a useful marker of disease activity in RP.

Establishment of a novel experimental system using single cell-derived pleomorphic rhabdomyosarcoma cell lines expressing K-RasG12V and deficient in p53.

Pleomorphic rhabdomyosarcoma (PRMS) predominantly arises in adult skeletal musculature and is usually associated with poor prognosis. Thus, effective treatments must be developed. PRMS is a rare tumor; therefore, it is critical to develop an experimental system to understand the cellular and molecular mechanisms of PRMS. We previously demonstrated that PRMS develops after p53 gene deletion and oncogenic K-Ras expression in the skeletal muscle tissue. In that study, oncogenic K-Ras-expressing cells were diverse and the period until disease onset was difficult to control. In this study, we developed an experimental system to address this problem. Single cell-derived murine cell lines, designated as RMS310 and RMSg2, were established by limiting the dilution of cells from a lung metastatic tumor colony that were positive for various cancer stem cells and activated skeletal muscle-resident stem/progenitor cell marker genes by RT-PCR. All cell lines stably recapitulated the histological characteristics of human PRMS as bizarre giant cells, desmin-positive cells, and lung metastases in C57BL/6 mice. All subclones of the RMSg2 cells by the limiting dilution in vitro could seed PRMS subcutaneously, and as few as 500 RMSg2 cells were sufficient to form tumors. These results suggest that the RMSg2 cells are multipotent cancer cells that partially combine the properties of skeletal muscle-resident stem/progenitor cells and high tumorigenicity. Thus, our model system's capacity to regenerate tumor tissue in vivo and maintain stable cells in vitro makes it useful for developing therapeutics to treat PRMS.

Evaluation of airway involvement and treatment in patients with relapsing polychondritis.

Airway involvement in relapsing polychondritis (RP) can be debilitating and life threatening, often requiring interventional procedures. If standard therapies including systemic corticosteroid and immunosuppressive agents are ineffective, airway stenting is often required. Recently, biologics have been reported to be effective for RP, and the early administration of biologics may avoid airway stenting. To evaluate survival rates and treatment approaches, medical records of RP patients with airway involvement were reviewed. These cases were divided into the following groups: with and without malacia, stenting and non-stenting, and with and without biologics. Kaplan-Meier was used to calculate survival rates and log rank tests were used to analyze biologics groups. A total of 77 patients were enrolled. Airway stenting was performed in 13 patients, all of which developed airway malacia. The stenting group had significantly lower survival rates than the non-stenting group (p < 0.001). Stent-related complications were granulation tissue (85%) and mucostasis (69%). In the non-stenting group, a lower mortality rate was observed. A significantly higher survival rate was seen in patients administered biologics than without (p = 0.014). The early administration of biologics shows promise in preventing severe airway disorders that require airway stenting.

Development and preclinical efficacy of novel transforming growth factor-ß1 short interfering RNAs for pulmonary fibrosis.

Idiopathic pulmonary fibrosis is a chronic devastating disease of unknown etiology. No therapy is currently available. A growing body of evidence supports the role of transforming growth factor (TGF)-ß1 as the major player in the pathogenesis of the disease. However, attempts to control its expression and to improve the outcome of pulmonary fibrosis have been disappointing. We tested the hypothesis that TGF-ß1 is the dominant factor in the acute and chronic phases of pulmonary fibrosis and developed short interfering (si)RNAs directed toward molecules implicated in the disease. This study developed novel sequences of siRNAs targeting the TGF-ß1 gene and evaluated their therapeutic efficacy in two models of pulmonary fibrosis: a model induced by bleomycin and a novel model of the disease developed spontaneously in mice overexpressing the full length of human TGF-ß1 in the lungs. Intrapulmonary delivery of aerosolized siRNAs of TGF-ß1 with sequences common to humans and rodents significantly inhibited bleomycin-induced pulmonary fibrosis in the acute and chronic phases of the disease and in a dose-dependent manner. Aerosolized human-specific siRNA also efficiently inhibited pulmonary fibrosis, improved lung function, and prolonged survival in human TGF-ß1 transgenic mice. Mice showed no off-target effects after intratracheal administration of siRNA. These results suggest the applicability of these novel siRNAs as tools for treating pulmonary fibrosis in humans.

Overexpression of phospholipase Cε in keratinocytes upregulates cytokine expression and causes dermatitis with acanthosis and T-cell infiltration.

Phospholipase Cε (PLCε) is an effector of Ras and Rap small GTPases. We showed previously using PLCε-deficient mice that PLCε plays a critical role in activation of cytokine production in non-immune skin cells in a variety of inflammatory reactions. For further investigation of its role in inflammation, we created transgenic mice overexpressing PLCε in epidermal keratinocytes. The resulting transgenic mice spontaneously developed skin inflammation as characterized by formation of adherent silvery scales, excessive growth of keratinocytes, and aberrant infiltration of immune cells such as T cells and DC. Development of the skin symptoms correlated well with increased expression of factors implicated in human inflammatory skin diseases, such as IL-23, in keratinocytes, and with the accumulation of CD4(+) T cells producing IL-22, a potent inducer of keratinocyte proliferation. Intradermal injection of a blocking antibody against IL-23 as well as treatment with the immunosuppressant FK506 reversed these skin phenotypes, which was accompanied by suppression of the IL-22-producing T-cell infiltration. These results reveal a crucial role of PLCε in the development of skin inflammation and suggest a mechanism in which PLCε induces the production of cytokines including IL-23 from keratinocytes, leading to the activation of IL-22-producing T cells.

Overexpression of SPACIA1/SAAL1, a newly identified gene that is involved in synoviocyte proliferation, accelerates the progression of synovitis in mice and humans.

OBJECTIVE: To identify novel genes associated with dysregulated proliferation of activated synovial fibroblasts, which are involved in arthritic joint destruction. METHODS: We performed transcriptome analysis to identify genes that were up-regulated in the foot joints of mice with collagen-induced arthritis (CIA). The effect of candidate genes on proliferation of synovial fibroblasts was screened using antisense oligodeoxynucleotides and small interfering RNAs (siRNAs). We characterized the expression and function of a novel gene, synoviocyte proliferation-associated in collagen-induced arthritis 1 (SPACIA1)/serum amyloid A-like 1 (SAAL1) using antibodies and siRNA and established transgenic mice to examine the effect of SPACIA1/SAAL1 overexpression in CIA. RESULTS: Human and mouse SPACIA1/SAAL1 encoded 474 amino acid proteins that shared 80% homology. SPACIA1/SAAL1 was primarily expressed in the nucleus of rheumatoid arthritis (RA) synovial fibroblasts and was highly expressed in the hyperplastic lining of inflamed synovium. In addition, its expression level in RA- or osteoarthritis (OA)-affected synovial tissue was positively correlated with the thickness of the synovial lining. Furthermore, SPACIA1/SAAL1 siRNA inhibited the proliferation of synovial fibroblasts, especially tumor necrosis factor α-induced synovial fibroblasts, by blocking entry into the S phase without inducing apoptosis. Finally, transgenic mice overexpressing SPACIA1/SAAL1 exhibited early onset and rapid progression of CIA. CONCLUSION: These results suggest that SPACIA1/SAAL1 is necessary for abnormal proliferation of synovial fibroblasts and its overexpression is associated with the progression of synovitis in mice and humans. Thus, therapy targeting SPACIA1/SAAL1 might have potential as an inhibitor of synovial proliferation in RA and/or OA.

Role of SDF1/CXCR4 interaction in experimental hemiplegic models with neural cell transplantation.

Much attention has been focused on neural cell transplantation because of its promising clinical applications. We have reported that embryonic stem (ES) cell derived neural stem/progenitor cell transplantation significantly improved motor functions in a hemiplegic mouse model. It is important to understand the molecular mechanisms governing neural regeneration of the damaged motor cortex after the transplantation. Recent investigations disclosed that chemokines participated in the regulation of migration and maturation of neural cell grafts. In this review, we summarize the involvement of inflammatory chemokines including stromal cell derived factor 1 (SDF1) in neural regeneration after ES cell derived neural stem/progenitor cell transplantation in mouse stroke models.

Mechanical model of steady-state and inflammatory conditions in patients with relapsing polychondritis: A review.

ABSTRACT: Relapsing polychondritis (RP) is a multisystem inflammatory disorder, considered to associate with immune aberration.Increased T helper type-1 cell-related cytokines were reported in RP patients. mRNA expressions of a regulatory T cell cytokine interleukin (IL)-10 increased, whereas pro-inflammatory cytokines IL1ß and IL6 mRNA expressions decreased in freshly isolated peripheral blood mononuclear cells of RP patients compared with those in healthy individuals. Upon in vitro stimulation with mitogen, IL10 mRNA expressions decreased, and IL1ß and IL6 mRNA expressions increased in RP patients.This short-time dynamic change of gene expressions from anti-inflammatory to pro-inflammatory features of immune cells may be associated with the "relapsing" disease course of patients with RP. IL1ß mRNA expressions of peripheral blood mononuclear cells exhibited positive correlations with serum matrix metalloproteinase (MMP)-3 concentrations in patients with respiratory involvement. Such positive correlation was not found in those without respiratory involvement.In a metagenomic analysis, an altered composition of gut microbes was found, suggesting that microbe metabolites such as short-chain fatty acids may affect T cell responses of the patients.In this review, the relationships among RP-related inflammatory molecules were summarized. The data support a hypothesis that the immune conditions are different between steady-state and inflammation in RP patients.

Nationwide cross-sectional survey of patients with relapsing polychondritis in 2019 demonstrates reduction of airway involvement compared with that in 2009.

We conducted retrospective cohort studies of patients with relapsing polychondritis (RP) twice in 2009 and 2019, using a physician questionnaire. We compared the patients' clinical statuses between the years. Age and gender were comparable between the two surveys. Mean disease duration was longer in 2019 survey (8.3 years) than that in 2009 survey (4.8 years, P < 0.001). The mortality rate declined in 2019 survey compared with those in 2009 survey (from 9.2 to 1.6%, P < 0.001). Incidence of airway involvement decreased in 2019 survey compared with that in 2009 survey (from 49 to 37%, P = 0.012). In 2019 survey, we found more frequent use of biological agents and immunosuppressants in patients with airway involvement. When we focused on RP patients with airway involvement, physicians in 2019 chose methotrexate and calcineurin inhibitors preferentially, compared with azathioprine and cyclophosphamide. Of note is that increased use of infliximab was observed in RP patients with airway involvement, but not in those without. Reduction of airway involvement and mortality in patients with RP was observed in 2019 survey. The reduction may associate with the frequent use of biologics including infliximab in RP patients with airway involvement.