Mesenchymal stem cells preconditioned with a TLR5 agonist enhanced immunoregulatory effect through M2 macrophage polarization in a murine graft-versus-host disease model.

Graft-versus-host disease (GVHD) is a common complication following hematopoietic stem cell transplantation and can be life-threatening. Mesenchymal stem cells (MSCs), adult stem cells with immunomodulatory properties, have been used as therapeutic agents in a variety of ways and have demonstrated efficacy against acute GVHD (aGVHD); however, variability in MSC pro- and anti-inflammatory properties and the limitation that they only exhibit immunosuppressive effects at high levels of inflammation have prevented their widespread clinical use. The outcomes of GVHD treated with MSCs in the clinic have been variable, and the underlying mechanisms remain unclear. Therefore, the unique biological effects of Toll-like receptor 5 (TLR5) agonists led us to compare and validate the efficacy of MSCs primed with KMRC011, a TLR5 agonist. KMRC011 is a stimulant that induces the secretion of cytokines, which play an important role in immune regulation. In this study, we found that MSCs pretreated with KMRC011 increased the secretion of immunosuppressive cytokines indoleamine 2,3-dioxygenase (IDO) and cyclooxygenase-2 (COX2) and increased the expression of M2 macrophage polarizing cytokines macrophage colony-stimulating factor (M-CSF) and interleukin 10 (IL-10) in vitro. We investigated the immunosuppressive effects of TLR5 agonist (KMRC011)-primed MSCs on lymphocytes and their preventive and therapeutic effects on an in vivo mouse aGVHD model. In vitro experiments showed that KMRC011-primed MSCs had enhanced immunosuppressive effects on lymphocyte proliferation. In vivo experiments showed that KMRC011-primed MSCs ameliorated GVHD severity in a mouse model of induced GVHD disease. Finally, macrophages harvested from the spleens of mice treated with KMRC011-primed MSCs showed a significant increase in the anti-inflammatory M2 phenotype. Overall, the results suggest that KMRC011-primed MSCs attenuated GVHD severity in mice by polarizing macrophages to the M2 phenotype and increasing the proportion of anti-inflammatory cells, opening new horizons for GVHD treatment.

Repeated Infusions of Bone-Marrow-Derived Mesenchymal Stem Cells over 8 Weeks for Steroid-Refractory Chronic Graft-versus-Host Disease: A Prospective, Phase I/II Clinical Study.

Chronic graft-versus-host disease (cGVHD) is a long-term complication of allogeneic hematopoietic stem cell transplantation associated with poor quality of life and increased morbidity and mortality. Currently, there are several approved treatments for patients who do not respond to steroids, such as ruxolitinib. Nevertheless, a significant proportion of patients fail second-line treatment, indicating the need for novel approaches. Mesenchymal stem cells (MSCs) have been considered a potential treatment approach for steroid-refractory cGVHD. To evaluate the safety and efficacy of repeated infusions of MSCs, we administered intravenous MSCs every two weeks to ten patients with severe steroid-refractory cGVHD in a prospective phase I clinical trial. Each patient received a total of four doses, with each dose containing 1 × 106 cells/kg body weight from the same donor and same passage. Patients were assessed for their response to treatment using the 2014 National Institutes of Health (NIH) response criteria during each visit. Ten patients with diverse organ involvement were enrolled, collectively undergoing 40 infusions as planned. Remarkably, the MSC infusions were well tolerated without severe adverse events. Eight weeks after the initial MSC infusion, all ten patients showed partial responses characterized by the amelioration of clinical symptoms and enhancement of their quality of life. The overall response rate was 60%, with a complete response rate of 20% and a partial response (PR) rate of 40% at the last follow-up. Overall survival was 80%, with a median follow-up of 381 days. Two patients died due to relapse of their primary disease. Immunological analyses revealed a reduction in inflammatory markers, including Suppression of Tumorigenicity 2 (ST2), C-X-C motif chemokine ligand (CXCL)10, and Secreted phosphoprotein 1(SPP1), following the MSC treatment. Repeated MSC infusions proved to be both feasible and safe, and they may be an effective salvage therapy in patients with steroid-refractory cGVHD. Further large-scale clinical studies with long-term follow-up are needed in the future to determine the role of MSCs in cGVHD.

The IL-6 signaling pathway contributes critically to the immunomodulatory mechanism of human decidua-derived mesenchymal stromal cells.

Human bone marrow-derived mesenchymal stromal cells (BM-MSCs) have been proposed as a treatment for graft-versus-host disease (GVHD), which is a major complication following allogeneic hematopoietic cell transplantation. However, clinical trials have not yielded good results, and human decidua-derived mesenchymal stromal cells (DSCs) have been proposed as an alternative. In addition, the mechanism by which DSCs exert their immunomodulatory effects is still unknown. We found that knockdown of IL-6 in DSCs reduced the expression of PD-L1 and PD-L2, which are known as classical immune checkpoint inhibitors. Expression of PD-L1 and PD-L2 was restored by adding recombinant IL-6 to the DSCs. When DSCs and IL-6-knockdown DSCs were administered as treatment in a murine GVHD model, the group receiving IL-6-knockdown DSCs had significantly higher mortality and clinical scores compared to the group receiving DSCs. Taken together, these data suggest that the IL-6 signaling pathway is a crucial contributor to the immunosuppressive capacity of DSCs.

TLR5 agonist in combination with anti-PD-1 treatment enhances anti-tumor effect through M1/M2 macrophage polarization shift and CD8+ T cell priming.

Immune checkpoint inhibitors have revolutionized anti-tumor therapy, notably improving treatment responses in various tumors. However, many patients remain non-responsive and do not experience benefits. Given that Toll-like receptors (TLRs) can counteract tumor immune tolerance by stimulating both innate and adaptive immune responses, TLR agonists are being explored as potential immune adjuvants for cancer treatment. In this study, we assessed the potential of enhancing the efficacy of immune checkpoint inhibitors by activating innate immunity with a TLR5 agonist. In a mouse tumor model, combination therapy with TLR5 agonist and anti-PD-1 significantly inhibited tumor growth. The TLR5 agonist shifted the balance from M2-like to M1-like macrophages and upregulated the expression of co-stimulatory molecules in macrophages. Furthermore, TLR5 agonist promoted the activation and tumor infiltration of CD8+ T cells. As a result, the TLR5 agonist augmented the anti-tumor efficacy of anti-PD-1, suggesting its potential in modulating the tumor microenvironment to enhance the anti-tumor response. Our findings point toward the possibility of optimizing immune checkpoint inhibitor therapy using TLR5 agonists.

Processing wh-filler-gap dependencies.

We present experimental evidence showing that different wh-filler-gap dependencies are processed differently, depending on their syntactic licensors. Our studies compared the active storage profiles for why, how, and who (serving as subject or object of the verb). The results of offline and online experiments revealed that these wh-fillers are stored in memory for different durations, and predictably so based on the hypothesised structural distance between each wh-filler and the licensor which determines its grammatical and interpretive functions. Furthermore, the results showed that once the wh-filler is licenced, it is integrated to the current structure, and no longer engenders additional memory costs. Based on these findings, we argue that the mechanism of online sentence processing may employ both storage and integration components in memory.

Zero-derivation in Korean: the effect of covert structure in real-time processing.

Korean words like balgda 'bright/become bright' and gilda 'long/become long' are categorially ambiguous; they can appear as both adjectives and verbs. Some suggest that these words are listed under separate lexical entries, while others propose that they share one single lexical entry, and that the verb form is morphologically derived from the base adjective through a process called zero derivation. This study presents the results of a real-time experiment that investigates whether these words involve zero derivation and if so, how zero derivation may affect the real-time processing of these words. Our findings suggest that the reader recognizes the base adjective and obtains the derived-verb form by virtue of adding a covert category-changing morpheme in real-time sentence processing. This study provides promising evidence of the zero derivation of Korean categorially ambiguous adjectives and verbs, as well as crosslinguistic evidence of the role of covert structure in lexical access.

HMBA ameliorates obesity by MYH9- and ACTG1-dependent regulation of hypothalamic neuropeptides.

The global epidemic of obesity remains a daunting problem. Here, we report hexamethylene bisacetamide (HMBA) as a potent anti-obesity compound. Peripheral and central administration of HMBA to diet-induced obese mice regulated the expression of hypothalamic neuropeptides critical for energy balance, leading to beneficial metabolic effects such as anorexia and weight loss. We found that HMBA bound to MYH9 and ACTG1, which were required for the anti-obesity effects of HMBA in both NPY-expressing and POMC-expressing neurons. The binding of HMBA to MYH9 and ACTG1 elevated the expression of HEXIM1 and enhanced its interaction with MDM2, resulting in the dissociation of the HEXIM1-p53 complex in hypothalamic cells. Subsequently, the free HEXIM1 and p53 translocated to the nucleus, where they downregulated the transcription of orexigenic NPY, but p53 and acetylated histone 3 upregulated that of anorexigenic POMC. Our study points to a previously unappreciated efficacy of HMBA and reveals its mechanism of action in metabolic regulation, which may propose HMBA as a potential therapeutic strategy for obesity.

BAFF blockade attenuates acute graft-versus-host disease directly via the dual regulation of T- and B-cell homeostasis.

Introduction: B-cell-activating factor (BAFF) is associated with donor-specific antibodies and chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the effects of BAFF on T-cell physiological function have not been fully elucidated in acute GVHD. Methods: We examined the effects of belimumab, a monoclonal antibody targeting BAFF, for the treatment of acute GVHD. We examined the effects of T cells and B cells separately when inducing GVHD in mouse model. Results: Therapeutic functional manipulation of endogenous BAFF can improve acute GVHD during the early post-transplant period. In this study, BAFF was shown to increase the proportions of CD4+IL-17+, CD4+IL-6+ Th17, and CD4+IFN-γ+ Th1 cells and to reduce the proportion of regulatory T (Treg) cells. Furthermore, the belimumab therapy group showed increased B220+IgD+IgM+ mature B cells but decreased B220+IgD-IgM- memory B cells, B220+Fas+GL-7+ germinal center formation, and B220+IgD-CD138+ plasma cells. These results indicate that BAFF can alleviate acute GVHD by simultaneously regulating T and B cells. Interestingly, the BAFF level was higher in patients with acute GVHD after HSCT compared with patients receiving chemotherapy. Conclusion: This study suggests that BAFF blockade might modulate CD4 +T-cell-induced acute GVHD early after allo-HSCT and the possibility of simultaneously controlling chronic GVHD, which may appear later after allo-HSCT.

The Puzzle of Argument Structure Mismatch in Gapping.

Voice mismatch between conjuncts is impossible in the gapping construction. Some recent studies explained this effect by analyzing gapping as involving the ellipsis of a category at least as large as VoiceP. One prediction this analysis makes is that mismatch of any head structurally lower than Voice (e.g., little v) should not be possible in gapping. In this study, through a series of acceptability judgment experiments examining argument structure mismatches in gapping, we provide empirical observations that challenge this prediction.

Island-sensitivity of two different interpretations of why in Chinese.

It has been assumed that the wh-element weishenme "why" in Chinese has two distinct interpretations: a reason reading, which typically yields yinwei "because"-answers, and a purpose reading, which typically triggers weile "in order to"-answers. It is claimed that the two interpretations differ in island sensitivity: the reason weishenme is sensitive to islands while the purpose weishenme is not. Assuming that the reason weishenme is a wh-adverb without finer internal structure, while the purpose weishenme is a wh-PP consisting of the preposition wei "for" and a wh-DP shenme "what," this contrast in island sensitivity can be considered as an instance of a broader generalization: the so-called argument-adjunct asymmetry (or the DP-adverb asymmetry) of wh-in-situ island sensitivity. However, recent experimental studies provided mixed findings on whether the argument-adjunct asymmetry of wh-in-situ island sensitivity actually holds. The current study focuses on the two interpretations of weishenme "why/for what" in Chinese, and provides evidence using a formal acceptability judgment experiment that the two weishenmes are both sensitive to islands, contrary to previous generalizations. Our results provide further empirical challenge to the so-called argument-adjunct asymmetry of wh-in-situ island sensitivity.

Auranofin prevents liver fibrosis by system Xc-mediated inhibition of NLRP3 inflammasome.

Demand for a cure of liver fibrosis is rising with its increasing morbidity and mortality. Therefore, it is an urgent issue to investigate its therapeutic candidates. Liver fibrosis progresses following 'multi-hit' processes involving hepatic stellate cells, macrophages, and hepatocytes. The NOD-like receptor protein 3 (NLRP3) inflammasome is emerging as a therapeutic target in liver fibrosis. Previous studies showed that the anti-rheumatic agent auranofin inhibits the NLRP3 inflammasome; thus, this study evaluates the antifibrotic effect of auranofin in vivo and explores the underlying molecular mechanism. The antifibrotic effect of auranofin is assessed in thioacetamide- and carbon tetrachloride-induced liver fibrosis models. Moreover, hepatic stellate cell (HSC), bone marrow-derived macrophage (BMDM), kupffer cell, and hepatocyte are used to examine the underlying mechanism of auranofin. Auranofin potently inhibits activation of the NLRP3 inflammasome in BMDM and kupffer cell. It also reduces the migration of HSC. The underlying molecular mechanism was inhibition of cystine-glutamate antiporter, system Xc. Auranofin inhibits system Xc activity and instantly induced oxidative burst, which mediated inhibition of the NLRP3 inflammasome in macrophages and HSCs. Therefore, to the best of our knowledge, we propose the use of auranofin as an anti-liver fibrotic agent.

Physicochemical and biological similarity assessment of LBAL, a biosimilar to adalimumab reference product (Humira®).

LBAL was developed as an adalimumab (Humira®) biosimilar using Chinese hamster ovary cell lines. Comparable quality, safety, and efficacy between a biosimilar and its reference product should be ensured for regulatory approval. Here, we present the results of a comprehensive physicochemical and biological characterization between LBAL and Humira®. As physicochemical attributes, primary and higher-order structure, N-glycan profile, and disulfide linkage were investigated. Biological attributes were evaluated by target/receptor binding analysis and in vitro/ex vivo cell-based assays, which are linked to mechanisms of action. As a result, LBAL had the identical amino acid sequence, similar post-translational modifications and N-/C-terminal variants, and comparable primary, secondary, and tertiary structures and disulfide linkage profile. However, some differences in N-glycan profiles were observed. Biological activities, including tumor necrosis factor (TNF) binding, TNF-neutralization, apoptosis, Fc receptor binding, and complement-dependent cytotoxicity, were largely consistent. Despite a slightly lower antibody-dependent cellular cytotoxicity activity in LBAL, this difference was not significant under physiological conditions. As indicated, this extensive analytical characterization and functional comparison assessment showed that LBAL was similar to Humira®, with minor differences of no clinical relevance. Taken together, our comparative assessment of physicochemical and biological attributes demonstrated that LBAL is structurally and functionally very similar to Humira®, supporting the biosimilarity of clinical efficacy and safety.

Off-the-Shelf Partial HLA Matching SARS-CoV-2 Antigen Specific T Cell Therapy: A New Possibility for COVID-19 Treatment.

BACKGROUND: Immunological characteristics of COVID-19 show pathological hyperinflammation associated with lymphopenia and dysfunctional T cell responses. These features provide a rationale for restoring functional T cell immunity in COVID-19 patients by adoptive transfer of SARS-CoV-2 specific T cells. METHODS: To generate SARS-CoV-2 specific T cells, we isolated peripheral blood mononuclear cells from 7 COVID-19 recovered and 13 unexposed donors. Consequently, we stimulated cells with SARS-CoV-2 peptide mixtures covering spike, membrane and nucleocapsid proteins. Then, we culture expanded cells with IL-2 for 21 days. We assessed immunophenotypes, cytokine profiles, antigen specificity of the final cell products. RESULTS: Our results show that SARS-CoV-2 specific T cells could be expanded in both COVID-19 recovered and unexposed groups. Immunophenotypes were similar in both groups showing CD4+ T cell dominance, but CD8+ and CD3+CD56+ T cells were also present. Antigen specificity was determined by ELISPOT, intracellular cytokine assay, and cytotoxicity assays. One out of 14 individuals who were previously unexposed to SARS-CoV-2 failed to show antigen specificity. Moreover, ex-vivo expanded SARS-CoV-2 specific T cells mainly consisted of central and effector memory subsets with reduced alloreactivity against HLA-unmatched cells suggesting the possibility for the development of third-party partial HLA-matching products. DISCUSSION: In conclusion, our findings show that SARS-CoV-2 specific T cell can be readily expanded from both COVID-19 and unexposed individuals and can therefore be manufactured as a biopharmaceutical product to treat severe COVID-19 patients. ONE SENTENCE SUMMARY: Ex-vivo expanded SARS-CoV-2 antigen specific T cells developed as third-party partial HLA-matching products may be a promising approach for treating severe COVID-19 patients that do not respond to previous treatment options.

Human mesenchymal stem cells derived from umbilical cord and bone marrow exert immunomodulatory effects in different mechanisms.

BACKGROUND: Mesenchymal stem cells (MSCs) are an attractive tool to treat graft-versus-host disease because of their unique immunoregulatory properties. Although human bone marrow-derived MSCs (BM-MSCs) were the most widely used MSCs in cell therapy until recently, MSCs derived from human umbilical cords (UC-MSCs) have gained popularity as cell therapy material for their ethical and noninvasive collection. AIM: To investigate the difference in mechanisms of the immunosuppressive effects of UC-MSCs and BM-MSCs. METHODS: To analyze soluble factors expressed by MSCs, such as indolamine 2,3-dioxygenase, cyclooxygenase-2, prostaglandin E2 and interleukin (IL)-6, inflammatory environments in vitro were reconstituted with combinations of interferon-gamma (IFN-γ), tumor necrosis factor alpha and IL-1ß or with IFN-γ alone. Activated T cells were cocultured with MSCs treated with indomethacin and/or anti-IL-10. To assess the ability of MSCs to inhibit T helper 17 cells and induce regulatory T cells, induced T helper 17 cells were cocultured with MSCs treated with indomethacin or anti-IL-10. Xenogeneic graft-versus-host disease was induced in NOG mice (NOD/Shi-scid/IL-2Rγnull) and UC-MSCs or BM-MSCs were treated as cell therapies. RESULTS: Our data demonstrated that BM-MSCs and UC-MSCs shared similar phenotypic characteristics and immunomodulation abilities. BM-MSCs expressed more indolamine 2,3-dioxygenase after cytokine stimulation with different combinations of IFN-γ, tumor necrosis factor alpha-α and IL-1ß or IFN-γ alone. UC-MSCs expressed more prostaglandin E2, IL-6, programmed death-ligand 1 and 2 in the in vitro inflammatory environment. Cyclooxygenase-2 and IL-10 were key factors in the immunomodulatory mechanisms of both MSCs. In addition, UC-MSCs inhibited more T helper 17 cells and induced more regulatory T cells than BM-MSCs. UC-MSCs and BM-MSCs exhibited similar effects on attenuating graft-versus-host disease. CONCLUSION: UC-MSCs and BM-MSCs exert similar immunosuppressive effects with different mechanisms involved. These findings suggest that UC-MSCs have distinct immunoregulatory functions and may substitute BM-MBSCs in the field of cell therapy.

Processing gapping: Parallelism and grammatical constraints.

This study aims to test two hypotheses about the online processing of Gapping: whether the parser inserts an ellipsis site in an incremental fashion in certain coordinated structures (the Incremental Ellipsis Hypothesis), or whether ellipsis is a late and dispreferred option (the Ellipsis as a Last Resort Hypothesis). We employ two offline acceptability rating experiments and a sentence fragment completion experiment to investigate to what extent the distribution of Gapping is controlled by grammatical and extra-grammatical constraints. Furthermore, an eye-tracking while reading experiment demonstrated that the parser inserts an ellipsis site incrementally but only when grammatical and extra-grammatical constraints allow for the insertion of the ellipsis site. This study shows that incremental building of the Gapping structure follows from the parser's general preference to keep the structure of the two conjuncts maximally parallel in a coordination structure as well as from grammatical restrictions on the distribution of Gapping such as the Coordination Constraint.

Tanycytic TSPO inhibition induces lipophagy to regulate lipid metabolism and improve energy balance.

Hypothalamic glial cells named tanycytes, which line the 3rd ventricle (3V), are components of the hypothalamic network that regulates a diverse array of metabolic functions for energy homeostasis. Herein, we report that TSPO (translocator protein), an outer mitochondrial protein, is highly enriched in tanycytes and regulates homeostatic responses to nutrient excess as a potential target for an effective intervention in obesity. Administration of a TSPO ligand, PK11195, into the 3V, and tanycyte-specific deletion of Tspo reduced food intake and elevated energy expenditure, leading to negative energy balance in a high-fat diet challenge. Ablation of tanycytic Tspo elicited AMPK-dependent lipophagy, breaking down lipid droplets into free fatty acids, thereby elevating ATP in a lipid stimulus. Our findings suggest that tanycytic TSPO affects systemic energy balance through macroautophagy/autophagy-regulated lipid metabolism, and highlight the physiological significance of TSPO in hypothalamic lipid sensing and bioenergetics in response to overnutrition. ABBREVIATIONS: 3V: 3rd ventricle; ACAC: acetyl-Coenzyme A carboxylase; AGRP: agouti related neuropeptide; AIF1/IBA1: allograft inflammatory factor 1; AMPK: AMP-activated protein kinase; ARC: arcuate nucleus; Atg: autophagy related; Bafilo: bafilomycin A1; CAMKK2: calcium/calmodulin-dependent protein kinase kinase 2, beta; CCCP: carbonyl cyanide m-chlorophenylhydrazone; CNS: central nervous system; COX4I1: cytochrome c oxidase subunit 4I1; FFA: free fatty acid; GFAP: glial fibrillary acidic protein; HFD: high-fat diet; ICV: intracerebroventricular; LAMP2: lysosomal-associated membrane protein 2; LD: lipid droplet; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MBH: mediobasal hypothalamus; ME: median eminence; MEF: mouse embryonic fibroblast; NCD: normal chow diet; NEFM/NFM: neurofilament medium; NPY: neuropeptide Y; OL: oleic acid; POMC: pro-opiomelanocortin-alpha; PRKN/Parkin: parkin RBR E3 ubiquitin protein ligase; Rax: retina and anterior neural fold homeobox; RBFOX3/NeuN: RNA binding protein, fox-1 homolog (C. elegans) 3; RER: respiratory exchange ratio; siRNA: small interfering RNA; SQSTM1: sequestosome 1; TG: triglyceride; TSPO: translocator protein; ULK1: unc-51 like kinase 1; VCO2: carbon dioxide production; VMH: ventromedial hypothalamus; VO2: oxygen consumption.

Down-regulation of intracellular reactive oxygen species attenuates P-glycoprotein-associated chemoresistance in Epstein-Barr virus-positive NK/T-cell lymphoma.

Epstein-Barr virus (EBV)-positive extranodal NK/T-cell lymphoma is a rare and highly aggressive disease with a poor prognosis and strong resistance to anti-cancer drugs. Reactive oxygen species (ROS) are closely related to tumorigenesis and P-glycoprotein (P-gp) is highly expressed in various cancers. However, the exact relationship between ROS and P-gp in EBV-positive lymphoma remains unclear. In this study, we demonstrated that EBV latent infection induced intracellular ROS production and increased ROS levels triggered elevated P-gp expression, which resulted in strong resistance to existing anti-cancer drugs in EBV-positive lymphoma cell lines and in patients' tissue samples. We also verified that regulation of intracellular ROS reduced P-gp expression and function via inhibition of STAT1 phosphorylation. These results indicate that treatment with a ROS scavenger is a potential therapeutic strategy to overcome resistance to anti-cancer drugs by downregulating the expression of P-gp in EBV-positive NK/T-cell lymphoma.

Regulation of HMGB1 release protects chemoradiotherapy-associated mucositis.

Oral mucositis (OM) is a common complication in cancer patients undergoing anticancer treatment. Despite the clinical and economic consequences of OM, there are no drugs available for its fundamental control. Here we show that high-mobility group box 1 (HMGB1), a "danger signal" that acts as a potent innate immune mediator, plays a critical role in the pathogenesis of OM. In addition, we investigated treatment of OM through HMGB1 blockade using NecroX-7 (tetrahydropyran-4-yl)-[2-phenyl-5-(1,1-dioxo-thiomorpholin-4-yl)methyl-1Hindole-7-yl]amine). NecroX-7 ameliorated basal layer epithelial cell death and ulcer size in OM induced by chemotherapy or radiotherapy. This protective effect of NecroX-7 was mediated by inhibition of HMGB1 release and downregulation of mitochondrial oxidative stress. Additionally, NecroX-7 inhibited the HMGB1-induced release of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1ß, and macrophage inflammatory protein (MIP)-1ß, as well as the expression of p53-upregulated modulator of apoptosis (PUMA) and the excessive inflammatory microenvironment, including nuclear factor-kB (NF-kB) pathways. In conclusion, our findings suggest that HMGB1 plays a key role in the pathogenesis of OM; therefore, blockade of HMGB1 by NecroX-7 may be a novel therapeutic strategy for OM.

Enhancement of Graft-Versus-Host Disease Control Efficacy by Adoptive Transfer of Type 1 Regulatory T Cells in Bone Marrow Transplant Model.

Interleukin (IL)-10-producing type 1 regulatory T (Tr1) cells, which are Foxp3-memory T lymphocytes, play important roles in peripheral immune tolerance. We investigated whether Tr1 cells exert immunoregulatory effects in a mouse model of acute graft-versus-host disease (GVHD). Mouse CD4+ T cells were induced to differentiate in vitro into Tr1 cells using vitamin D3 and dexamethasone, and these donor-derived Tr1 cells were infused on the day of bone marrow transplantation. The Tr1 cell-transferred group showed less weight-loss and a twofold higher survival rate than the GVHD group, together with markedly decreased histopathologic grades. It was associated with the expansion of CD4+IL-4+ type 2 T-helper (Th2) cells and CD4+CD25+Foxp3+ regulatory T (Treg) cells. Furthermore, Tr1 cells decreased the numbers of CD4+interferon-γ+ Th1 and CD4+IL-17+ Th17 cells. Recipient mice harbored some Foxp3+ Tregs due to adoptive transfer of Tr1 cells, together with the upregulated expression of costimulatory molecules, including cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and inducible T-cell costimulator (ICOS); however, the Treg cells did not show the plasticity. Therefore, adoptive Tr1 cell therapy may be effective against manifestations of GVHD, exert immunomodulatory effects in a manner dependent on CTLA-4 and ICOS, and induce differentiation of the transferred Tr1 cells into Foxp3+ Treg cells.