IL-18 receptor-α signalling pathway contributes to autoantibody-induced arthritis via neutrophil recruitment and mast cell activation

OBJECTIVES

The interleukin (IL)-18 signalling pathway is involved in animal models of collagen-induced arthritis, but the role of this pathway in autoantibody-induced arthritis is poorly understood. An autoantibody-induced arthritis model, K/BxN serum transfer arthritis, reflects the effector phase of arthritis and is important in innate immunity including neutrophils and mast cells. This study aimed to investigate the role of the IL-18 signalling pathway in autoantibody-induced arthritis using IL-18 receptor (IL-18R) α-deficient mice.

METHODS

K/BxN serum transfer arthritis was induced in IL-18Rα-/- and wild-type B6 (controls) mice. The severity of arthritis was graded, and histological and immunohistochemical examinations were performed on paraffin-embedded ankle sections. Total Ribonucleic acid (RNA) isolated from mouse ankle joints was analysed by real-time reverse transcriptase-polymerase chain reaction.

RESULTS

IL-18 Rα-/- mice had significantly lower arthritis clinical scores, neutrophil infiltration, and numbers of activated, degranulated mast cells in the arthritic synovium than in controls. IL-1β, which is indispensable for the progression of arthritis, was significantly downregulated in inflamed ankle tissue in IL-18 Rα-/- mice.

CONCLUSIONS

IL-18/IL-18Rα signalling contributes to the development of autoantibody-induced arthritis by enhancing synovial tissue expression of IL-1β and inducing neutrophil recruitment and mast cell activation. Therefore, inhibition of the IL-18Rα signalling pathway might be a new therapeutic strategy for rheumatoid arthritis.

Enhanced GATA4 expression in senescent systemic lupus erythematosus monocytes promotes high levels of IFNα production

Enhanced interferon α (IFNα) production has been implicated in the pathogenesis of systemic lupus erythematosus (SLE). We previously reported IFNα production by monocytes upon activation of the stimulator of IFN genes (STING) pathway was enhanced in patients with SLE. We investigated the mechanism of enhanced IFNα production in SLE monocytes. Monocytes enriched from the peripheral blood of SLE patients and healthy controls (HC) were stimulated with 2'3'-cyclic GAMP (2'3'-cGAMP), a ligand of STING. IFNα positive/negative cells were FACS-sorted for RNA-sequencing analysis. Gene expression in untreated and 2'3'-cGAMP-stimulated SLE and HC monocytes was quantified by real-time PCR. The effect of GATA binding protein 4 (GATA4) on IFNα production was investigated by overexpressing GATA4 in monocytic U937 cells by vector transfection. Chromatin immunoprecipitation was performed to identify GATA4 binding target genes in U937 cells stimulated with 2'3'-cGAMP. Differentially expressed gene analysis of cGAS-STING stimulated SLE and HC monocytes revealed the enrichment of gene sets related to cellular senescence in SLE. CDKN2A, a marker gene of cellular senescence, was upregulated in SLE monocytes at steady state, and its expression was further enhanced upon STING stimulation. GATA4 expression was upregulated in IFNα-positive SLE monocytes. Overexpression of GATA4 enhanced IFNα production in U937 cells. GATA4 bound to the enhancer region of IFIT family genes and promoted the expressions of IFIT1, IFIT2, and IFIT3, which promote type I IFN induction. SLE monocytes with accelerated cellular senescence produced high levels of IFNα related to GATA4 expression upon activation of the cGAS-STING pathway.

Latent ion tracks were finally observed in diamond

Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C60 fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which π-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS). Since the melting transition is not induced in diamond at atmospheric pressure, conventional inelastic thermal spike calculations cannot be applied. Two-temperature molecular dynamics simulations succeeded in the reproduction of both the track formation under MeV C60 irradiations and the no-track formation under GeV monoatomic ion irradiations.

Pretreatment circulating MAIT cells, neutrophils, and periostin predicted the real-world response after 1-year mepolizumab treatment in asthmatics

BACKGROUND

Mepolizumab treatment improves symptom control and quality of life and reduces exacerbations in patients with severe eosinophilic asthma. However, biomarkers that predict therapeutic effectiveness must be determined for use in precision medicine. Herein, we elucidated the dynamics of various parameters before and after treatment as well as patient characteristics predictive of clinical responsiveness to mepolizumab after 1-year treatment.

METHODS

Twenty-seven patients with severe asthma were treated with mepolizumab for one year. Asthma control test scores, pulmonary function tests, fractional exhaled nitric oxide levels, and blood samples were evaluated. Additionally, we explored the role of CD69-positive mucosal-associated invariant T (MAIT) cells as a candidate biomarker for predicting treatment effectiveness by evaluating an OVA-induced asthma murine model using MR1 knockout mice, where MAIT cells were absent.

RESULTS

The frequencies of CD69-positive group 1 innate lymphoid cells, group 3 innate lymphoid cells, natural killer cells, and MAIT cells decreased after mepolizumab treatment. The frequency of CD69-positive MAIT cells and neutrophils was lower and serum periostin levels were higher in responders than in non-responders. In the OVA-induced asthma murine model, CD69-positive MAIT cell count in the whole mouse lung was significantly higher than that in the control mice. Moreover, OVA-induced eosinophilic airway inflammation was exacerbated in the MAIT cell-deficient MR1 knockout mice.

CONCLUSIONS

This study shows that circulating CD69-positive MAIT cells, neutrophils, and serum periostin might predict the real-world response after 1-year mepolizumab treatment. Furthermore, MAIT cells potentially have a protective role against type 2 airway inflammation.

Sex, Age, and Ethnic Background Shape Adaptive Immune Responses Induced by the SARS-CoV-2 mRNA Vaccine

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine-induced adaptive responses have been well investigated. However, the effects of sex, age, and ethnic background on the immune responses elicited by the mRNA vaccine remain unclear. Here, we performed comprehensive analyses of adaptive immune responses elicited by the SARS-CoV-2 mRNA vaccine. Vaccine-induced antibody and T cell responses declined over time but persisted after 3 months, and switched memory B cells were even increased. Spike-specific CD4⁺ T and CD8⁺ T cell responses were decreased against the B.1.351 variant, but not against B.1.1.7. Interestingly, T cell reactivity against B.1.617.1 and B.1.617.2 variants was decreased in individuals carrying HLA-A24, suggesting adaptive immune responses against variants are influenced by different HLA haplotypes. T follicular helper cell responses declined with increasing age in both sexes, but age-related decreases in antibody levels were observed only in males, and this was associated with the decline of T peripheral helper cell responses. In contrast, vaccine-induced CD8⁺ T cell responses were enhanced in older males. Taken together, these findings highlight that significant differences in the reactogenicity of the adaptive immune system elicited by mRNA vaccine were related to factors including sex, age, and ethnic background.

Different Spatial and Temporal Roles of Monocytes and Monocyte-Derived Cells in the Pathogenesis of an Imiquimod Induced Lupus Model

Mounting evidence indicates the importance of aberrant Toll-like receptor 7 (TLR7) signaling in the pathogenesis of systemic lupus erythematosus (SLE). However, the mechanism of disease progression remains unclear. An imiquimod (IMQ)-induced lupus model was used to analyze the lupus mechanism related to the aberrant TLR7 signals. C57BL/6 mice and NZB/NZW mice were treated with topical IMQ, and peripheral blood, draining lymph nodes, and kidneys were analyzed focusing on monocytes and monocyte-related cells. Monocytes expressed intermediate to high levels of TLR7, and the long-term application of IMQ increased Ly6C^lo monocytes in the peripheral blood and Ly6C^lo monocyte-like cells in the lymph nodes and kidneys, whereas Ly6C^hi monocyte-like cell numbers were increased in lymph nodes. Ly6C^lo monocyte-like cells in the kidneys of IMQ-induced lupus mice were supplied by bone marrow-derived cells as demonstrated using a bone marrow chimera. Ly6C^lo monocytes obtained from IMQ-induced lupus mice had upregulated adhesion molecule-related genes, and after adoptive transfer, they showed greater infiltration into the kidneys compared with controls. RNA-seq and post hoc PCR analyses revealed Ly6C^lo monocyte-like cells in the kidneys of IMQ-induced lupus mice had upregulated macrophage-related genes compared with peripheral blood Ly6C^lo monocytes and downregulated genes compared with kidney macrophages (MF). Ly6C^lo monocyte-like cells in the kidneys upregulated Il6 and chemoattracting genes including Ccl5 and Cxcl13. The higher expression of Il6 in Ly6C^lo monocyte-like cells compared with MF suggested these cells were more inflammatory than MF. However, MF in IMQ-induced lupus mice were characterized by their high expression of Cxcl13. Genes of proinflammatory cytokines in Ly6C^hi and Ly6C^lo monocytes were upregulated by stimulation with IMQ but only Ly6C^hi monocytes upregulated IFN-α genes upon stimulation with 2′3′-cyclic-GMP-AMP, an agonist of stimulator of interferon genes. Ly6C^hi and Ly6C^lo monocytes in IMQ-induced lupus mice had different features. Ly6C^hi monocytes responded in the lymph nodes of locally stimulated sites and had a higher expression of IFN-α upon stimulation, whereas Ly6C^lo monocytes were induced slowly and tended to infiltrate into the kidneys. Infiltrated monocytes in the kidneys likely followed a trajectory through inflammatory monocyte-like cells to MF, which were then involved in the development of nephritis.

Low energy excitation in liquid Sb and liquid Bi observed in inelastic x-ray scattering spectra

The dynamic structure factorS(Q,E), whereQandEare momentum and energy transfer, respectively, has been measured for liquid Sb, using inelastic x-ray scattering. A modified damped harmonic oscillator model function was applied to analyseS(Q,E) of liquid Sb and also to that of liquid Bi by Inuiet al(2015Phys. Rev.B92, 054206). The obtained excitation energy was in fairly good agreement with that predicted byab initiomolecular dynamics simulations on these liquid semi-metals. The excitation energy of the longitudinal acoustic mode in liquid Sb and liquid Bi exhibits flat-toppedQdependence whereas the lower excitation energy below the longitudinal acoustic excitation showsQ-gap behaviour. From the viscosity estimated from theQ-gap experimentally obtained, it is inferred that the lower energy excitation arises from the transverse acoustic excitation in the liquids.

Characteristics of mucosal-associated invariant T cells and their roles in immune diseases

Mucosal-associated invariant T (MAIT) cells are a subset of innate-like T cells that express a semi-invariant T cell receptor and are restricted by the molecule major histocompatibility complex class I-related molecule 1 (MR1). MAIT cells recognize biosynthetic derivatives of the riboflavin synthesis pathway present in microbes. MAIT cells have attracted increased interest related to various immune responses because of their unique features including their abundance in humans, nonpeptidic antigens, and ability to respond to antigenic and non-antigenic stimuli. The numbers of circulating MAIT cells are decreased in many immune diseases such as multiple sclerosis, systemic lupus erythematosus, and inflammatory bowel diseases. However, the remaining MAIT cells have an increased cytokine-producing capacity and activated status, which is related to disease activity. Additionally, MAIT cells have been observed at sites of inflammation including the kidneys, synovial fluid and intestinal mucosa. These findings suggest their involvement in the pathogenesis of immune diseases. In this mini-review, we summarize the recent findings of MAIT cells in human immune diseases and animal models, and discuss their role and potential as a therapeutic target.

Modeling the effects of contact-tracing apps on the spread of the coronavirus disease: Mechanisms, conditions, and efficiency

This study simulates the spread of the coronavirus disease (COVID-19) using a detailed agent-based model and the census data of Japan to provide a comprehensive analysis of the effects of contact-tracing apps. The model assumes two types of response to the app notification: the notified individuals quarantine themselves (type-Q response) or they get tested (type-T response). The results reveal some crucial characteristics of the apps. First, type-Q response is successful in achieving containment; however, type-T response has a limited curve-flattening effect. Second, type-Q response performs better than type-T response because it involves quarantine of those who are infected but have not become infectious yet, and the current testing technology cannot detect the virus in these individuals. Third, if the download rate of the apps is extremely high, type-Q response can achieve virus containment with a small number of quarantined people and thereby high efficiency. Finally, given a fixed download rate, increasing the number of tests per day enhances the effectiveness of the apps, although the degree of improved effectiveness is not proportional to the change in the number of tests.

Activated Mucosal-associated Invariant T Cells Have a Pathogenic Role in a Murine Model of Inflammatory Bowel Disease

BACKGROUND & AIMS

Mucosal-associated invariant T (MAIT) cells are innate-like T cells restricted by major histocompatibility complex-related molecule 1 (MR1) and express a semi-invariant T cell receptor. Previously, we reported the activation status of circulating MAIT cells in patients with ulcerative colitis (UC) was associated with disease activity and that these cells had infiltrated the inflamed colonic mucosa. These findings suggest MAIT cells are involved in the pathogenesis of inflammatory bowel disease. We investigated the role of MAIT cells in the pathogenesis of colitis by using MR1^-/- mice lacking MAIT cells and a synthetic antagonistic MR1 ligand.

METHODS

Oxazolone colitis was induced in MR1^-/- mice (C57BL/6 background), their littermate wild-type controls, and C57BL/6 mice orally administered an antagonistic MR1 ligand, isobutyl 6-formyl pterin (i6-FP). Cytokine production of splenocytes and colonic lamina propria lymphocytes from mice receiving i6-FP was analyzed. Intestinal permeability was assessed in MR1^-/- and i6-FP-treated mice and their controls. The effect of i6-FP on cytokine production by MAIT cells from patients with UC was assessed.

RESULTS

MR1 deficiency or i6-FP treatment reduced the severity of oxazolone colitis. i6-FP treatment reduced cytokine production in MAIT cells from mice and patients with UC. Although MR1 deficiency increased the intestinal permeability, i6-FP administration did not affect gut integrity in mice.

CONCLUSIONS

These results indicate MAIT cells have a pathogenic role in colitis and suppression of MAIT cell activation might reduce the severity of colitis without affecting gut integrity. Thus, MAIT cells are potential therapeutic targets for inflammatory bowel disease including UC.

Resolution of One-Year Persisting COVID-19 Pneumonia and Development of Immune Thrombocytopenia in a Follicular Lymphoma Patient With Preceding Rituximab Maintenance Therapy: A follow-up Report and Literature Review of Cases With Prolonged Infections

Background

We previously reported elsewhere of a follicular lymphoma patient suffering from persistent COVID-19 pneumonia that was still ongoing at 2 months after onset.

Materials and Methods

We provide a follow-up report of the case along with a literature review of immunocompromised lymphoma patients experiencing prolonged COVID-19 infections.

Results

Although requiring a full 1 year, the presented case eventually achieved spontaneous resolution of COVID-19 pneumonia. Anti-SARS-CoV-2 antibodies could not be detected throughout the disease course, but COVID-19-directed T-cell response was found to be intact. The patient also developed secondary immune thrombocytopenia subsequent to COVID-19 pneumonia. We found 19 case reports of immunocompromised lymphoma patients with prolonged COVID-19 infections in the literature. All 5 patients who died did not receive convalescent plasma therapy, whereas resolution of COVID-19 infection was achieved in 8 out of 9 patients who received convalescent plasma therapy.

Conclusions

We demonstrate through the presented case that while time-consuming, resolution of COVID-19 infections may be achieved without aid from humoral immunity if cellular immunity is intact. Immunocompromised lymphoma patients are at risk of a prolonged disease course of COVID-19, and convalescent plasma therapy may be a promising approach in such patients.

Peripartum changes in serum activities of three major alkaline phosphatase isoenzymes in Holstein dairy cows

This study investigated changes in serum levels of hepatic, bone, and intestinal alkaline phosphatase (ALP) isoenzymes (ALP2, ALP3, and ALP5, respectively) in Holstein cows around parturition. Tartrate-resistant acid phosphatase 5b (TRAP5b) activity and calcium (Ca) concen-trations were also measured. We analyzed blood samples from 11 late-pregnant heifers (primipa-rous group) and 13 multiparous (2-4 lactations; multiparous group) cows at 3 weeks (18-24 days prepartum; -3 weeks), 2 weeks (17-11 days prepartum; -2 weeks), and 1 week (10-4 days prepar-tum; -1 weeks) before parturition; the day of calving (within 12 h post-calving; day 0); and 5 days postpartum (5 days). ALP3 activity was significantly higher in the primiparous group than in the multiparous group, whereas the activities decreased significantly in both groups after 5 days. ALP2 and ALP5 activities did not change, whereas ALP2 activity was significantly higher in the primiparous group than in the multiparous group. TRAP5b activity was significantly higher in the primiparous group than in the multiparous group and showed a transient significant increase at day 0. Ca concentration significantly decreased at day 0 in both groups; the Ca level at day 0 was significantly higher in the primiparous group than in the multiparous group. These data show that ALP3 activity in serum may indicate a change in osteoblastic bone forma-tion after calving, but further study is needed to determine the clinical application for measuring ALP isoenzymes in bovine medicine.

The effectiveness of mobility control, shortening of restaurants' opening hours, and working from home on control of COVID-19 spread in Japan

Since the first outbreak of COVID-19, various interventions have been implemented to prevent the global spread of the virus. Using an agent-based model that describes the attributes and mobility of the Japanese population, the present research evaluates the effectiveness of mobility control, shortening of restaurants' opening hours, and working from home. Results show that early and severe mobility control that restricts 90% of domestic travel decreases the peak cases by 40%, compared to no intervention implementation. Mobility control that only limits movement to and from highly populated regions is as effective as nationwide travel restrictions. Furthermore, shortening of restaurants’ opening hours is the most effective intervention in a state of emergency; it should be utilized even after the emergency. However, working from home has comparatively limited effects.

Agarose gel electrophoresis pattern of serum alkaline phosphatase isoenzymes in Holstein cows during lactation

A recent study found that an agarose gel electrophoresis (AGE) method yielded two distinct major bands corresponding to the hepatic and bone ALP isoenzymes (ALP2 and ALP3, respec-tively) in bovine serum treated with protease and neuraminidase (PN-treatment), although there were concerns that the intestinal ALP isoenzyme (ALP5) often overlapped with ALP3 in human serum treated with neuraminidase. Because ALP5 was separated from ALP3 in bovine serum treated with protease alone (P-treatment), we used a modified method employing both P- and PN-treated bovine sera to measure the activities of the three ALP isoenzymes in 53 lacta-ting Holstein cows: 24 primiparous and 29 multiparous. Upon electrophoresis, 51 of 53 samples (96.2%) subjected to P-treatment yielded a distinct fraction corresponding to ALP5, as did the control serum. All PN-treated sera yielded a definite ALP2 fraction. The ALP3 fraction was calculated as the remainder after excluding ALP2 and ALP5. The activities of total ALP (t-ALP) and ALP3 in primiparous cows were higher than those in multiparous cows (p ⟨ 0.001) at early-to-peak [10-110 days in milk (DIM)] and mid (111-220 DIM) lactation. In the multi-parous cows, the ALP3 activity at late lactation (221-477 DIM) was significantly higher than that at early-to-peak lactation. Thus, the modified AGE method described here is able to discrimi-nate three fractions of ALP isoenzymes in the sera of lactating cows. The AGE pattern of circu-lating ALP isoenzymes will contribute to the understanding of the physiological bone metabolism status in lactating cows.

Mucosal-Associated Invariant T Cells Are Involved in Acute Ischemic Stroke by Regulating Neuroinflammation

Background Mucosal-associated invariant T (MAIT) cells have been associated with inflammation in several autoimmune diseases. However, their relation to ischemic stroke remains unclear. This study attempted to elucidate the role of MAIT cells in acute ischemic stroke in mice. Methods and Results We used MR1 knockout C57BL/6 (MR1-/-) mice and wild-type littermates (MR1+/+). After performing a transient middle cerebral artery occlusion (tMCAO), we evaluated the association with inflammation and prognosis in the acute cerebral ischemia. Furthermore, we analyzed the tMCAO C57BL/6 mice administered with the suppressive MR1 ligand and the vehicle control. We also evaluated the infiltration of MAIT cells into the ischemic brain by flow cytometry. Results showed a reduction of infarct volume and an improvement of neurological impairment in MR1-/- mice (n=8). There was a reduction in the number of infiltrating microglia/macrophages (n=3-5) and in their activation (n=5) in the peri-infarct area of MR1-/- mice. The cytokine levels of interleukin-6 and interleukin-17 at 24 hours after tMCAO (n=3-5), and for interleukin-17 at 72 hours after tMCAO (n=5), were lower in the MR1-/- mice. The administration of the suppressive MR1 ligand reduced the infarct volume and improved functional impairment (n=5). Flow cytometric analysis demonstrated there was a reduction of MAIT cells infiltrating into the ischemic brain at 24 hours after tMCAO (n=17). Conclusions Our results showed that MAIT cells play an important role in neuroinflammation after focal cerebral ischemia and the use of MAIT cell regulation has a potential role as a novel neuroprotectant for the treatment of acute ischemic stroke.

Inhibition of mTOR suppresses IFNα production and the STING pathway in monocytes from systemic lupus erythematosus patients

OBJECTIVE

Increased IFNα is important in the pathogenesis of SLE. Plasmacytoid dendritic cells are considered the main producer of IFNα upon Toll-like receptor pathway activation. However, which cells produce IFNα following stimulation with cyclic GMP-AMP synthase (cGAS) and stimulator of IFN genes (STING) in SLE remains unknown. We investigated the IFNα producing capacity of myeloid cells under cGAS-STING pathway stimulation.

METHODS

IFNα levels in peripheral blood mononuclear cells from SLE patients and healthy controls stimulated with 2'3'c-GAMP, a stimulator of cGAS-STING, were measured by intracellular cytokine staining and flow cytometry. STING expression and its co-localization with TBK1 were examined by flow cytometry or confocal microscopy. The effects of in vitro exposure to IFNα on IFNα production and STING expression, and in vitro rapamycin treatment on IFNα production and STING, pTBK1 and IRF3 expression were examined.

RESULTS

IFNα was produced by monocytes, conventional dendritic cells and plasmacytoid dendritic cells upon cGAS-STING pathway activation. The frequency of IFNα-producing monocytes positively correlated with SLE disease activity. STING expression and its co-localization with TBK1 were increased in lupus monocytes. Prior exposure to IFNα enhanced the IFNα-producing capacity of monocytes. Inhibition of the mechanistic target of the rapamycin (mTOR) pathway suppressed IFNα production from monocytes and downregulated enhanced STING expression and its downstream molecules.

CONCLUSION

Enhanced IFNα from lupus monocytes induced by augmented STING pathway activation is associated with SLE pathogenesis. Suppression of the mTOR pathway downregulated the enhanced STING expression and the subsequent IFNα production by monocytes.

Association of mucosal-associated invariant T cells with different disease phases of polymyalgia rheumatica

OBJECTIVES

Although T cells are thought to be involved in the pathogenesis of PMR, whether innate-like T cells are involved in the process remains unknown.

METHODS

The serum levels of 27 cytokines/chemokines in patients with PMR were measured by a multiplex immunoassay (Bio-Plex Assay). The cytokine-producing capacity of T and innate-like T cells was assessed by intracellular cytokine staining and flow cytometry. The frequency and activated status of T and innate-like T cells were investigated by flow cytometry and their associations with clinical parameters were assessed.

RESULTS

The levels of inflammatory cytokines were associated with disease activity in PMR. The cytokine-producing capacity by CD8+ T and innate-like T cells was associated with disease activity. The frequency of HLA-DR+ CD38+ cells among CD8+ T cells was increased in patients with active disease. The frequencies of HLA-DR+ CD38+ cells among CD4+ T, mucosal-associated invariant T (MAIT) and γδ T cells were higher in patients with inactive disease. The frequency of HLA-DR+ CD38+ MAIT cells was associated with the PMR activity score and CRP levels in patients in remission.

CONCLUSION

The inflammatory cytokine-producing capacity and expression of activation markers of CD8+ T and innate-like T cells were associated with the disease activity of PMR. MAIT cell activation in patients in remission may contribute to the subclinical activity of the disease.

Ion tracks in silicon formed by much lower energy deposition than the track formation threshold

Damaged regions of cylindrical shapes called ion tracks, typically in nano-meters wide and tens micro-meters long, are formed along the ion trajectories in many insulators, when high energy ions in the electronic stopping regime are injected. In most cases, the ion tracks were assumed as consequences of dense electronic energy deposition from the high energy ions, except some cases where the synergy effect with the nuclear energy deposition plays an important role. In crystalline Si (c-Si), no tracks have been observed with any monomer ions up to GeV. Tracks are formed in c-Si under 40 MeV fullerene (C₆₀) cluster ion irradiation, which provides much higher energy deposition than monomer ions. The track diameter decreases with decreasing the ion energy until they disappear at an extrapolated value of ~ 17 MeV. However, here we report the track formation of 10 nm in diameter under C₆₀ ion irradiation of 6 MeV, i.e., much lower than the extrapolated threshold. The diameters of 10 nm were comparable to those under 40 MeV C₆₀ irradiation. Furthermore, the tracks formed by 6 MeV C₆₀ irradiation consisted of damaged crystalline, while those formed by 40 MeV C₆₀ irradiation were amorphous. The track formation was observed down to 1 MeV and probably lower with decreasing the track diameters. The track lengths were much shorter than those expected from the drop of S_e below the threshold. These track formations at such low energies cannot be explained by the conventional purely electronic energy deposition mechanism, indicating another origin, e.g., the synergy effect between the electronic and nuclear energy depositions, or dual transitions of transient melting and boiling.

Matrix-material dependence on the elongation of embedded gold nanoparticles induced by 4 MeV C60 and 200 MeV Xe ion irradiation

We report the elongation of embedded Au nanoparticles (NPs) in three different matrices, i.e. amorphous carbon (a-C), crystalline indium tin oxide (In_xSn_1-xO_z; ITO) and crystalline calcium fluoride (CaF₂), under irradiations of 4 MeV C₆₀ ⁺ cluster ions and 200 MeV Xe¹⁴⁺ ions. Under 4 MeV C₆₀ cluster irradiation, strong sputtering is induced in CaF₂ layer so that the whole the layer was completely lost at a fluence of 5 × 10¹³ ions cm^-2. Au NPs were partly observed in the SiO₂, probably due to the recoil implantation. Amorphous carbon (a-C) layer exhibits low sputtering loss even under 4 MeV C₆₀ irradiation. However, the elongation in a-C layer was low. While the ITO layer showed a certain decrease in thickness under 4 MeV C₆₀ irradiation, large elongation of Au NPs was observed under both 4 MeV C₆₀ and 200 MeV Xe irradiation. The ITO layer preserved the crystallinity even after large elongation was induced. This is the first report of the elongation of metal NPs in a crystalline matrix.

Expanded circulating peripheral helper T cells in systemic lupus erythematosus: association with disease activity and B cell differentiation

OBJECTIVE

Peripheral helper T (TPH) cells are a recently identified Th cell subset that promotes B cell differentiation and antibody production in inflamed tissues. This study investigated circulating TPH cells to determine their involvement in systemic lupus erythematosus (SLE).

METHODS

Peripheral blood mononuclear cells collected from SLE patients and healthy individuals were analysed. TPH cells were identified as CD3+CD4+CD45RA-CXCR5- cells with a high expression of PD-1. The frequency, activation status and subsets of TPH cells were evaluated by flow cytometry. The production of IL-21 was assessed by intracellular staining and the association of TPH cells with disease activity and B cell populations was determined.

RESULTS

Circulating TPH cells, identified as CD3+CD4+CD45RA-PD-1highCXCR5- cells were increased in the peripheral blood of SLE patients compared with controls. Circulating TPH cells produced similar amounts of IL-21 compared with follicular Th cells. The expansion and activation of TPH cells were correlated with SLE disease activity. Activated TPH cells, particularly Th1-type TPH cells, were associated with the promotion of B cell differentiation in SLE patients.

CONCLUSION

The association of TPH cells with disease activity suggests the involvement of extrafollicular T-B cell interactions in the pathogenesis of SLE. TPH cells promote autoantibody production in aberrant lymphoid organs and therefore might be a novel therapeutic target in autoantibody-producing disorders.

Reconstitution of Circulating Mucosal-Associated Invariant T Cells after Allogeneic Hematopoietic Cell Transplantation: Its Association with the Riboflavin Synthetic Pathway of Gut Microbiota in Cord Blood Transplant Recipients

Mucosal-associated invariant T (MAIT) cells are a type of innate lymphocyte and recognize riboflavin (vitamin B2) synthesis products presented by MHC-related protein 1. We investigated long-term reconstitution of MAIT cells and its association with chronic graft-versus-host disease (cGVHD) in a cross-sectional cohort of 173 adult patients after allogeneic hematopoietic cell transplantation. According to donor source, the number of MAIT cells significantly correlated with time after cord blood transplantation (CBT) but not with time after bone marrow transplantation or peripheral blood stem cell transplantation. The number of MAIT cells was significantly lower in patients with cGVHD compared with patients without cGVHD. We also examined the association between MAIT cell reconstitution and gut microbiota as evaluated by 16S ribosomal sequencing of stool samples 1 mo post-CBT in 27 adult patients undergoing CBT. The diversity of gut microbiota was positively correlated with better MAIT cell reconstitution after CBT. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States analysis indicated that amounts of ribB and ribA genes were significantly higher in the microbiomes of patients with subsequent MAIT cell reconstitution after CBT. In conclusion, long-term MAIT cell reconstitution is dependent on the type of donor source. Our data also unveiled an important role for the interaction of circulating MAIT cells with gut microbiota in humans.

Unique primed status of microglia under the systemic autoimmune condition of lupus-prone mice

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of various autoantibodies. This disease causes disabling neuropsychiatric symptoms even in the absence of apparent inflammation in the central nervous system (CNS), but the mechanisms involved remain unknown. Innate immune-mediated inflammation has attracted attention as a pathogenic mechanism in neuropsychiatric diseases.

METHODS

We investigated the CNS of lupus-prone mice focusing on innate immunity. Three strains of lupus-prone mice, FcγRIIB^-/-Yaa, an F1 hybrid of NZB and NZW (NZB/NZW) mice, and MRL/Fas^lpr (MRL/lpr) mice were used to analyze CNS immunopathology.

RESULTS

Flow cytometry analysis demonstrated the numbers of brain CD45⁺ cells were increased compared with controls in lupus-prone mice. Upregulation of MHC class I and PDCA1 was observed in microglia and CD11b⁺ myeloid cells of lupus-prone mice, indicating they were activated in response to interferons (IFN). Microglial gene expression analysis of FcγRIIB^-/-Yaa mice revealed the upregulation of IFN-responsive genes and inflammation-related genes including Axl, Clec7a, and Itgax, which were previously reported in neurodegenerative conditions and primed conditions. Upregulated chemokine gene expressions including Ccl5 and Cxcl10 were concurrent with increased numbers of T cells and monocytes, especially Ly6C^lo monocytes in the CNS. Upregulation of Axl, Clec7a, Itgax, Ccl5, and Cxcl10 was also observed in NZB/NZW mice, indicating common lupus pathology. The primed status of microglia in FcγRIIB^-/-Yaa mice was also demonstrated by morphological changes such as enlarged cell bodies with hypertrophic processes, and hyperreactivity to lipopolysaccharide. Immunohistochemistry of FcγRIIB^-/-Yaa mice indicated reactive responses of astrocytes and vascular endothelium. Behavioral studies of FcγRIIB^-/-Yaa mice revealed depressive-like behavior and heat hyperalgesia in the forced swim test and the tail-flick test, respectively.

CONCLUSIONS

Our data indicated that microglia in lupus exhibit a unique primed phenotype characterized by the upregulated expressions of neurodegeneration-related genes and IFN-responsive genes. Interaction with peripheral cells and brain resident cells was presumed to orchestrate neuroinflammation. Targeting innate immune cells, such as microglia and monocytes, may be a promising therapeutic approach for neuropsychiatric SLE.

A Critical Role for Mucosal-Associated Invariant T Cells as Regulators and Therapeutic Targets in Systemic Lupus Erythematosus

Mucosal-associated invariant T (MAIT) cells are a subset of innate-like lymphocytes that are restricted by major histocompatibility complex-related molecule 1 (MR1). In this study, we investigated the role of MAIT cells in the pathogenesis of lupus in FcγRIIb^−/−Yaa mice, a spontaneous animal model of lupus. Using two approaches of MAIT cell deficiency, MR1 knockout animals and a newly synthesized inhibitory MR1 ligand, we demonstrate that MAIT cells augment the disease course of lupus by enhancing autoantibody production and tissue inflammation. MR1 deficiency reduced germinal center responses and T cell responses in these mice. Suppression of MAIT cell activation by the inhibitory MR1 ligand reduced autoantibody production and lupus nephritis in FcγRIIb^−/−Yaa mice. MAIT cells directly enhanced autoantibody production by B cells in vitro. Our results indicate the contribution of MAIT cells to lupus pathology and the potential of these cells as novel therapeutic targets for autoimmune diseases such as lupus.

The influence of temperature during water-quench rapid heat treatment on the microstructure, mechanical properties and biocompatibility of Ti6Al4V ELI alloy

This study investigates the influence of a rapid heat treatment followed by water-quenching on the mechanical properties of Ti6Al4V ELI alloy to improve its strength for use in implants. Prior to the experiment, a dilatometry test was performed to understand the progressive α-to β-phase transformation taking place during heating. The results were then used to carry out heat treatments. Microstructure was analysed using SEM, EBSD, EDX and XRD techniques. Vickers micro-hardness, tensile and high cycle rotating bending tests were used to analyse the influence of the $\alpha'$-phase fraction on the strength of the studied alloy. Results show that this process can provide a Ti6Al4V ELI alloy with a better Yield Strength (YS)/uniform deformation (ε_u) ratio and improved high cycle fatigue strength than those observed in the current microstructure used in medical implants. Lastly, cytotoxicity tests were performed on two types of human cells, namely MG63 osteoblast-like cells and fibroblasts. The results reveal the non-toxicity of the heat-treated Ti6Al4V ELI alloy.

Abstract PD8-07: Does resection of cavity shave margins result in lower positive margin and re-excision rates in patients with stage 0-III breast cancer? Results from a prospective multicenter randomized controlled trial

INTRODUCTION: Routine resection of cavity shave margins has been shown in single center studies to result in a significant reduction in positive margin and re-excision rates. In this prospective multicenter randomized controlled trial, we sought to validate these findings across practice settings.

METHODS: Nine centers across the United States, varying in practice setting and patient population, participated in this clinical trial of 398 stage 0-III breast cancer patients undergoing partial mastectomy (with or without resection of selective cavity margins). Participants were stratified by clinical stage and randomized 1:1 to either have routine cavity shave margins resected (“shave”) or not (“no shave”). Randomization group was revealed to the surgeon intraoperatively, after they had completed their standard partial mastectomy and were ready to close. Positive margins were defined as “tumor at ink” for invasive cancer or within 2 mm for ductal carcinoma in situ (DCIS). Adverse events were defined as seromas requiring percutaneous drainage, and/or hematomas or abscesses requiring operative intervention.

RESULTS: Median patient age was 65 (range; 29-94). 116 patients had invasive disease, 74 had DCIS, 179 had both, and 29 had no residual cancer at the time of partial mastectomy. The median invasive cancer size was 1.2 cm (range; 0.05-8.00 cm); the median extent of DCIS was 0.9 cm (range; 0.05-6.40 cm). The “shave” and “no shave” groups were well matched at baseline for clinicopathologic and demographic factors.

FactorShave (n=197)No Shave (n=201)p-valueAge (years); median (range)67 (36-94)64 (29-89)0.585Race  0.062-- White173 (87.8%)164 (81.6%) -- Black20 (10.2%)33 (16.4%) -- Asian2 (1.0%)2 (1.0%) -- Native American0 (0%)2 (1.0%) -- Unknown/Declined2 (1.0%)0 (0%) Hispanic ethnicity28 (14.2%)32 (15.9%)0.806Invasive tumor size (cm); median (range)1.30 (0.09-8.00)1.20 (0.05-7.50)0.282DCIS extent (cm); median (range)0.80 (0.10-6.40)1.00 (0.05-5.50)0.906Invasive histology  0.556-- Ductal177 (89.8%)186 (92.5%) -- Lobular16 (8.1%)13 (6.5%) -- Mucinous3 (1.5%)2 (1.0%) -- Other1 (0.5%)0 (0%) Neoadjuvant therapy15 (7.6%)19 (9.5%)0.592Palpable tumor57 (28.9%)56 (27.9%)0.825Node positive*24 (16.3%)16 (10.6%)0.175*Of the 298 patients who had lymph nodes evaluated

Prior to randomization, positive margin rates were similar in the “shave” and “no shave” groups (38.1% vs. 37.3%, respectively, p=0.918). After randomization, however, those in the “shave” group were significantly less likely than those in the “no shave” group to have positive margins (8.6% vs. 37.3%, respectively, p<0.001). They were also less likely to require re-excision or mastectomy for margin clearance (8.6% vs. 23.9%, p<0.001). There were no significant differences between the two groups in terms of adverse events (p=0.280). Rates of seroma (1.5% vs. 0.5%, p=0.368), hematoma (0.5% vs. 0.5%, p=1.000) and abscess (0.3% vs. 0%, p=0.495) were similar between the “shave” and “no shave” groups, respectively.

CONCLUSION: Resection of cavity shave margins significantly reduces positive margin and re-excision rates in patients with stage 0-III breast cancer undergoing partial mastectomy.

Citation Format: Chagpar AB, Tsangaris T, Garcia-Cantu C, Howard-McNatt M, Chiba A, Berger AC, Levine E, Gass JS, Gallagher K, Lum SS, Martinez RD, Willis AI, Pandya SV, Brown EA, Fenton A, Mendiola A, Murray M, Haddad V, Solomon NL, Senthil M, Bansil H, Ollila D, Snyder SK, Edmonson D, Lazar M, Namm JP, Li F, Butler M, McGowan NE, Herrera ME, Avitan YP, Yoder B, Dupont E. Does resection of cavity shave margins result in lower positive margin and re-excision rates in patients with stage 0-III breast cancer? Results from a prospective multicenter randomized controlled trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD8-07.

Osteopontin-targeted probe detects orthotopic breast cancers using optoacoustic imaging

Improved detection of breast cancer using highly sensitive, tumor-specific imaging would facilitate diagnosis, surveillance and assessment of response to treatment. We conjugated osteopontin peptide to an infrared fluorescent dye to serve as a contrast agent for detection of breast cancer by multispectral optoacoustic tomography (MSOT). Selective binding of the osteopontin-based probe was identified using flow cytometry and near infrared fluorescent imaging in triple negative and HER2 positive breast cancer cell lines in vitro. Osteopontin-750 accumulation was evaluated in vivo using MSOT with secondary confirmation of signal accumulation using near infrared fluorescent imaging. The osteopontin-based probe demonstrated binding to breast cancer cells in vitro. Similarly, after intravenous administration of the osteopontin-750 probe, it accumulated preferentially in the subcutaneous breast tumor in nude mice (557 MSOT a.u. compared to untargeted organs such as kidney (53.7 MSOT a.u.) and liver (32.1 MSOT a.u.). At 2.5 h post-injection, signal intensity within the tumor was 9.7 and 17 times greater in the tumor bed than in the kidney or liver, respectively. Fluorescence imaging ex vivo comparing tumor signal to that of nontarget organs confirmed the results in vivo. MSOT imaging demonstrated selective accumulation of the fluorescent osteopontin targeting probe to tumor sites both in vitro and in vivo, and provided high-resolution images. Further development of this tool is promising for advanced diagnostic imaging, disease surveillance and therapeutic models that limit nontarget toxicity.

Mucosal-Associated Invariant T Cells in Autoimmune Diseases

Mucosal-associated invariant T (MAIT) cells are innate T cells restricted by MHC-related molecule 1 (MR1). MAIT cells express semi-invariant T-cell receptors TRAV1-2-TRAJ33/12/20 in humans and TRAV1-TRAJ33 in mice. MAIT cells recognize vitamin B2 biosynthesis derivatives presented by MR1. Similar to other innate lymphocytes, MAIT cells are also activated by cytokines in the absence of exogenous antigens. MAIT cells have the capacity to produce cytokines, such as IFNγ, TNFα, and IL-17, and cytotoxic proteins, including perforin and granzyme B. MAIT cells were originally named after their preferential location in the mucosal tissue of the gut, but they are also abundant in other peripheral organs, including the liver and lungs. In humans, the frequency of MAIT cells is high in peripheral blood, and these cells constitute approximately 5% of circulating CD3⁺ cells. Their abundance in tissues and rapid activation following stimulation have led to great interest in their function in various types of immune diseases. In this review, first, we will briefly introduce key information of MAIT cell biology required for better understating their roles in immune responses, and then describe how MAIT cells are associated with autoimmune and other immune diseases in humans. Moreover, we will discuss their functions based on information from animal models of autoimmune and immunological diseases.

Breast-feeding regulates immune system development via transforming growth factor-β in mice pups

BACKGROUND

Breast milk contains important nutrients and immunoregulatory factors that are essential for newborn infants. Recently, epidemiological studies suggested that breast-feeding prevents a wide range of infectious diseases and lowers the incidence of infant allergic diseases.

METHODS

To examine the effects of breast milk on immunological development in infancy, we established an artificial rearing system for hand-feeding mice and compared mouse pups fed with either breast milk or milk substitute. All mice were killed at 14 days of age and immune cells in the thymus, spleen, and small intestine were examined on flow cytometry.

RESULTS

The number of thymocytes was higher whereas that of total immune cells of peripheral lymphoid tissues was lower in mice fed breast milk compared with milk substitute-fed mice. In peripheral lymphoid tissues, the proportion of B cells was higher and that of CD8+ T cells, macrophages, dendritic cells, and granulocytes was significantly lower in breast milk-fed mice. The same alteration in immune cells of the thymus and peripheral lymphoid tissues in milk substitute-fed mice was also observed in pups reared by mother mice treated with anti-transforming growth factor-β (anti-TGF-β) monoclonal antibody.

CONCLUSIONS

Breast milk regulates the differentiation and expansion of innate and adaptive immune cells partly due to TGF-β. Hence, TGF-β in breast milk may be a new therapeutic target for innate immune system-mediated diseases of infancy.

Enhanced IFN-α production is associated with increased TLR7 retention in the lysosomes of palasmacytoid dendritic cells in systemic lupus erythematosus

Background

Interferon-α (IFN-α) is increased and plays an important role in the pathogenesis of systemic lupus erythematosus (SLE). Plasmacytoid dendritic cells (pDCs) are the main producer of IFN-α, but their IFN-α producing capacity has been shown to be unchanged or reduced when stimulated with a Toll-like receptor 9 (TLR9) agonist in patients with SLE compared to in healthy individuals. In this study, we investigated the IFN-α-producing capacity of lupus pDCs under different stimulation.

Methods

pDCs from patients with SLE and healthy controls (HC) were stimulated with TLR9 or TLR7 agonist, and their IFN-α producing capacity was examined by intracellular cytokine staining and flow cytometry. The correlation of IFN-α-producing capacity with serum IFN-α levels and disease activity was assessed. The effect of in vitro IFN-α exposure on IFN-α production by pDCs was examined. Localization of TLR7 in cellular compartments in pDCs was investigated.

Results

The IFN-α producing capacity of pDCs was reduced after TLR9 stimulation, but increased when stimulated with a TLR7 agonist in SLE compared to in HC. IFN-α production by pDCs upon TLR9 stimulation was reduced and the percentage of IFN-α⁺pDC was inversely correlated with disease activity and serum IFN-α levels. However, the TLR7 agonist-induced IFN-α producing capacity of lupus pDCs was enhanced and correlated with disease activity and serum IFN-α. Exposure to IFN-α enhanced IFN-α production of TLR7-stimulated pDCs, but reduced that of pDCs activated with a TLR9 agonist. TLR7 localization was increased in late endosome/lysosome compartments in pDCs from SLE patients.

Conclusions

These findings indicate that enhanced TLR7 responses of lupus pDCs, owing to TLR7 retention in late endosome/lysosome and exposure to IFN-α, are associated with the pathogenesis of SLE.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1441-7) contains supplementary material, which is available to authorized users.

Circulating activated innate lymphoid cells and mucosal-associated invariant T cells are associated with airflow limitation in patients with asthma

BACKGROUND

A variety of innate subsets of lymphoid cells such as natural killer (NK) cells, several populations of innate lymphoid cells (ILCs), and mucosal-associated invariant T (MAIT) cells as innate-like T lymphocytes are involved in asthma and may have important effector functions in asthmatic immune responses. In the present study, we investigated whether NK cells, ILCs, and MAIT cells in the peripheral blood of patients with asthma would be associated with clinical asthma parameters.

METHODS

We recruited 75 adult patients with mild to severe asthma. The peripheral blood mononuclear cells in peripheral venous blood samples from the patients were purified and stained with different combinations of appropriate antibodies. The cells were analyzed by flow cytometry.

RESULTS

The percentage of activated (i.e., CD69⁺) NK cells in the total NK cell population was negatively correlated with FEV₁% which is calculated by the forced expiratory volume in 1 s (FEV₁)/the forced vital capacity (FVC). The percentages of CD69⁺ ILC1s and ILC2s were negatively correlated with FEV₁% and %FEV₁. The percentage of CD69⁺ ILC3s was positively correlated with BMI, and the percentage of CD69⁺ MAIT cells was negatively correlated with FEV₁%. Moreover, the percentage of CD69⁺ NK cells, ILC1s, ILC2s, ILC3s, and MAIT cells were positively correlated with each other.

CONCLUSIONS

For the first time, our data showed that activated NK cells, ILC1s, ILC2s, ILC3s, and MAIT cells were positively correlated with each other and may be associated with airflow limitation in patients with asthma.

Activation status of mucosal-associated invariant T cells reflects disease activity and pathology of systemic lupus erythematosus

Background

Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes constituting a large proportion of peripheral blood T cells expressing αβ T-cell receptor in humans. In this study, we aimed to investigate their involvement in systemic lupus erythematosus (SLE).

Methods

Peripheral blood MAIT cells from patients with SLE were assessed for their frequency, activation markers, and cell death by flow cytometry. The correlation between plasma cytokine levels and CD69 expression on MAIT cells was analyzed. The major histocompatibility complex class I-related protein MR1-restricted antigen-presenting capacity of antigen-presenting cells was investigated. Cytokine-mediated activation of MAIT cells in the absence of exogenous antigens was also examined.

Results

The frequency of MAIT cells was markedly reduced in SLE. The reduced number of MAIT cells was not attributable to the downregulation of surface markers, but it was partially due to the enhanced cell death of MAIT cells, possibly by activation-induced cell death. The CD69 expression levels on MAIT cells in SLE correlated with disease activity. Moreover, monocytes from patients with SLE exhibited increased ability to induce MAIT cell activation. The plasma concentration of interleukin (IL)-6, IL-18, and interferon (IFN)-α positively correlated with the expression levels of CD69 on MAIT cells in SLE. MAIT cells were activated by cytokines, including IFN-α, IL-15, and IL-12 plus IL-18, in the absence of exogenous antigens.

Conclusions

These results suggest that MAIT cells reflect the pathological condition of SLE and that their activated status correlates with presence of disease.

The dual role of short fatty acid chains in the pathogenesis of autoimmune disease models

Autoimmune diseases are influenced by both genetic and environmental factors. The gut environment has attracted much attention as an essential component that modulates immune responses, and therefore immune-mediated disorders, such as autoimmune diseases. Growing evidence suggests that microbiota and their metabolites are critical factors for immune modulation. Recently, we reported that the microbiome in patients with multiple sclerosis, an autoimmune disease targeting the myelin sheath of the central nervous system, is characterized by a reduction of bacteria belonging to Clostridia clusters IV and XIVa, which are potent producers of short-chain fatty acids (SCFAs) by fermentation of indigestible carbohydrates. In the present study, we investigated the role of SCFAs in the regulation of inflammation. We demonstrated that oral administration of SCFAs ameliorated the disease severity of systemic autoimmune inflammatory conditions mediated by lymphocytes such as experimental autoimmune encephalitis and collagen-induced arthritis. Amelioration of disease was associated with a reduction of Th1 cells and an increase in regulatory T cells. In contrast, SCFAs contributed to the exaggeration of K/BxN serum transfer arthritis, representing the effector phase of inflammation in rheumatoid arthritis. An increased understanding of the effect of microbiota metabolites will lead to the effective treatment and prevention of systemic inflammatory disorders.

Characterization of secondary ion emission processes of sub-MeV C60 ion impacts via analysis of statistical distributions of the emitted ion number

We report probability distributions of the number of secondary ions (SIs) emitted by sub-MeV C₆₀ ion impacts on an organic polymer target and the characterization of their emission processes through the analysis of the distributions. The probability distributions were obtained by analyzing experimental SI counting data obtained by a time-of-flight SI mass spectrometer combined with pulsed primary ion beams, using an analytical model developed to derive the distributions from the experimental data. A series of probability distribution functions was investigated for ion impacts of C₆₀ with sub-MeV energies (0.12-0.54 MeV), which can provide sufficient SIs per impact to determine the functions. Their complicated and undefined SI emission processes were characterized based on the determined functions.

Involvement of Mucosal-associated Invariant T cells in Ankylosing Spondylitis

Objective.

Ankylosing spondylitis (AS) is characterized by chronic inflammation of the axial and peripheral joints and ligamentous attachments. Gut immunity is thought to be involved in AS, because a prominent coexistence of gut and joint inflammation has been observed in patients with AS. Mucosal-associated invariant T (MAIT) cells are preferentially located in the gut lamina propria and produce inflammatory cytokines such as interleukin 17 (IL-17) and tumor necrosis factor-α (TNF-α), which are therapeutic targets for AS. This study aimed to investigate the involvement of MAIT cells in AS.

Methods.

The frequency of MAIT cells and their cytokine production were determined in patients with AS and healthy controls (HC). The expression of a MAIT cell activation marker (CD69) was analyzed in patients with AS by using flow cytometry.

Results.

The frequency of MAIT cells in the peripheral blood was lower in patients with AS compared with HC. The levels of IL-17 produced by MAIT cells after activation were higher in patients with AS than in the HC. CD69 expression on MAIT cells correlated with the Ankylosing Spondylitis Disease Activity Score in patients with AS.

Conclusion.

These results suggest the involvement of MAIT cells in the pathogenesis of AS.

Gut environment-induced intraepithelial autoreactive CD4(+) T cells suppress central nervous system autoimmunity via LAG-3

The gut environment has been found to significantly influence autoimmune diseases such as multiple sclerosis; however, immune cell mechanisms are unclear. Here we show that the gut epithelium of myelin oligodendrocyte glycoprotein(35-55)-specific T-cell receptor transgenic mice contains environmental stimuli-induced intraepithelial lymphocytes (IELs) that inhibit experimental autoimmune encephalomyelitis on transfer. These cells express surface markers phenotypical of 'induced' IELs, have a TH17-like profile and infiltrate the central nervous system (CNS). They constitutively express Ctla4 and Tgfb1 and markedly upregulate Lag3 expression in the CNS, thereby inhibiting inflammation. We also demonstrate the suppressive capability of CD4(+) IELs with alternative antigen specificities, their proliferation in response to gut-derived antigens and contribution of the microbiota and dietary aryl hydrocarbon receptor ligands to their induction. Thus, the gut environment favours the generation of autoreactive CD4(+) T cells with unique regulatory functions, potentially important for preventing CNS autoimmunity.

MAIT cells are activated and accumulated in the inflamed mucosa of ulcerative colitis

BACKGROUND AND AIM

Ulcerative colitis (UC) is a chronic, relapsing and remitting, inflammatory disorder of the large intestine. Mucosal associated invariant T (MAIT) cells are a member of innate-like lymphocytes found abundantly in the mucosal tissue. The contribution of MAIT cells in the pathogenesis of UC is still unclear; therefore, this study aimed at investigating the role of these cells in patients with UC.

METHODS

The frequency of MAIT cells, as well as the production of cytokines and expression levels of activation markers by these cells in the peripheral blood of UC patients and healthy controls, was analyzed by flow cytometry. MAIT cells were also quantified in colon biopsies of UC patients using a confocal microscope.

RESULTS

There was a significant reduction in MAIT cell frequency in the peripheral blood of UC patients compared with healthy controls (P < 0.0001). MAIT cells from UC patients secreted more interleukin (IL)-17 than healthy controls (P < 0.05). The expression levels of CD69 on these cells were correlated with disease activity and endoscopic scores and plasma levels of IL-18. Furthermore, MAIT cells increased in the inflamed mucosa, and their frequency was correlated with clinical and endoscopic disease activity in UC patients.

CONCLUSIONS

The findings from this study indicate that MAIT cells could be associated with UC and may serve as potential biomarkers or therapeutic targets in UC.

Gut intraepithelial myelin reactive CD4+T cells suppress central nervous system autoimmunity via LAG3

Objective

Multiple sclerosis (MS) is an autoimmune disease that targets the myelin of the central nervous system (CNS). Increasing incidence of MS in Japan let us question which components of the immune system are altered by environmental factors. Gut mucosa is by far the largest immune organ that interacts with the external environment. Since T cells are pivotal in controlling CNS inflammation, we investigated the existence of myelin reactive T cells that might be induced in the gut and their influence on CNS autoimmunity.

Methods

Gut-T cells from MOG(35–55) specific T cell receptor transgenic (2D2) mice were analyzed by FACS. Sorted gut-T cells were adoptively transferred to experimental autoimmune encephalomyelitis (EAE) induced by immunization with MOG(35–55). Blocking antibodies were used for functional analysis. Gut microbiota was modulated by oral antibiotics treatment. Diets including poor or rich aryl hydrocarbon receptor ligands (AHRL) were fed to mice.

Results

Here we demonstrate that the gut epithelium of 2D2 mice is inhabited by intraepithelial T-lymphocytes (IEL) that can inhibit EAE upon transfer. The regulatory IEL had the phenotype of CD4+‘induced’IEL (CD2+CD5+), exhibited TH17-like profile and had ability to infiltrate the inflamed CNS tissue. The IEL constitutively expressed Ctla4 and Tgfb1, and markedly upregulated Lag3 in the CNS, thereby inhibiting the inflammation. We also demonstrated that the IEL are induced by gut microbiota and AHRL.

Conclusions

Gut environment favors the generation of myelin reactive T cells that have unique regulatory function. Dysbiosis or poor AHRL in diet may reduce the induction of such regulatory cells, thus promoting the development of MS.

The effects of ethanol on the size-exclusion characteristics of type I dentin collagen to adhesive resin monomers

During dentin bonding with etch-and-rinse adhesive systems, phosphoric acid etching of mineralized dentin solubilizes the mineral crystallites and replaces them with bound and unbound water. During the infiltration phase of dentin bonding, solvated adhesive resin comonomers are supposed to replace all of the unbound collagen water and polymerize into copolymers. A recently published review suggested that dental monomers are too large to enter and displace water from tightly-packed collagen molecules. Conversely, recent work from the authors' laboratory demonstrated that HEMA and TEGDMA freely equilibrate with water-saturated dentin matrices. However, because adhesive blends are solvated in organic solvents, those solvents may remove enough free water to allow collagen molecules to come close enough to exclude adhesive monomer permeation. The present study analyzed the size-exclusion characteristics of dentin collagen, using a gel permeation-like column chromatography technique, filled with dentin powder instead of Sephadex beads as the stationary phase. The elution volumes of different sized test molecules, including adhesive resin monomers, studied in both water-saturated dentin, and again in ethanol-dehydrated dentin powder, showed that adhesive resin monomers can freely diffuse into both hydrated and dehydrated collagen molecules. Under these in vitro conditions, all free and some of the loosely-bound water seems to have been removed by ethanol. These results validate the concept that adhesive resin monomers can permeate tightly-bound water in ethanol-saturated collagen molecules during infiltration by etch-and-rinse adhesives.

STATEMENT OF SIGNIFICANCE

It has been reported that collagen molecules in dentin matrices are packed too close together to allow permeation of adhesive monomers between them. Resin infiltration, in this view, would be limited to extrafibrillar spaces. Our work suggests that monomers equilibrate with collagen water in both water and ethanol-saturated dentin matrices.

IL-38: A new factor in rheumatoid arthritis

The newly characterized cytokine IL-38 (IL-1F10) belongs to the IL-1 family of cytokines. Previous work has demonstrated that IL-38 inhibited Candida albicans-induced IL-17 production from peripheral blood mononuclear cells. However, it is still unclear whether IL-38 is an inflammatory or an anti-inflammatory cytokine. We generated anti-human IL-38 monoclonal antibodies in order to perform immunohistochemical staining and an enzyme-linked immunosorbent assay. While human recombinant IL-38 protein was not cleaved by recombinant caspase-1, chymase, or PR3 in vitro, overexpression of IL-38 cDNA produced a soluble form of IL-38 protein. Furthermore, immunohistochemical analysis showed that synovial tissues obtained from RA patients strongly expressed IL-38 protein. To investigate the biological role of IL-38, C57BL/6 IL-38 gene-deficient (^−/−) mice were used in an autoantibody-induced rheumatoid arthritis (RA) mouse model. As compared with control mice, IL-38 ^(−/−) mice showed greater disease severity, accompanied by higher IL-1β and IL-6 gene expression in the joints. Therefore, IL-38 acts as an inhibitor of the pathogenesis of autoantibody-induced arthritis in mice and may have a role in the development or progression of RA in humans.

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The soluble form of IL-38 is detected in the sera obtained from of RA patients.

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IL-38 protein was highly expressed in the synovial lining of RA synovium.

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IL-38 expression was up-regulated during arthritis in mice at the mRNA level.

•

IL-38 may attenuate joint inflammation by inhibiting the IL-1 induced inflammation.

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.