bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of Collagen Deposit in Obstructed Rat Bladder Outlet by Transplantation of Superparamagnetic Iron Oxide-Labeled Human Mesenchymal Stem Cells as Monitored by Molecular Magnetic Resonance Imaging (MRI)
Authors: Lee Hong Jun , Won Jong Ho , Doo Seung Hwan , Kim Jung Hoon , Song Ki Young , Lee Sun Ju , Lim Inja , Chang Kyu-Tae , Song Yun Seob , Kim Seung U.
Published: July 2012

Bladder outlet obstruction (BOO) caused by collagen deposit is one of the most common problems in elderly males. The present study is to investigate if human mesenchymal stem cells (MSCs) are capable of inhibiting collagen deposition and improve cystometric parameters in bladder outlet obstruction in rats. Human MSCs were labeled with nanoparticles containing superparamagnetic iron oxide (SPION), and transplanted in rat BOO lesion site. Forty 6-week-old female Sprague-Dawley rats were divided into four groups (group 1: control, group 2: sham operation, group 3: BOO, and group 4: BOO rats receiving SPION-hMSCs). Two weeks after the onset of BOO, 1 × 106 SPION-hMSCs were injected into the bladder wall. Serial T2-weighted MR images were taken immediately after transplantation of SPION-labeled human MSCs and at 4 weeks posttransplantation. T2-weighted MR images showed a clear hypointense signal induced by the SPION-labeled MSCs. While the expression of collagen and TGF-β protein increased after BOO, the expression of both returned to the original levels after MSC transplantation. Expression of HGF and c-met protein also increased in the group with MSC transplantation. Maximal voiding pressure and residual urine volume increased after BOO but they recovered after MSC transplantation. Human MSCs transplanted in rat BOO models inhibited the bladder fibrosis and mediated recovery of bladder dysfunction. Transplantation of MSC-based cell therapy could be a novel therapeutic strategy against bladder fibrosis in patients with bladder outlet obstruction.
Autologous Mesenchymal Stem Cells Prevent Transplant Arteriosclerosis by Enhancing Local Expression of Interleukin-10, Interferon-γ, and Indoleamine 2,3-dioxygenase
Authors: Jui Hsiang-Yiang , Lin Cheng-Hsin , Hsu Wan-Tseng , Liu Yi-Ru , Hsu Ron-Bin , Chiang Bor-Luen , Tseng Wen-Yih I. , Chen Ming-Fong , Wu Kenneth K. , Lee Chii-Ming
Published: July 2012

Transplant arteriosclerosis (TA) remains the major limitation of long-term graft survival in heart transplantation despite the advances in immunosuppressants. Mesenchymal stem cells (MSCs) have been demonstrated to suppress allogeneic immune responses by numerous in vitro studies. However, the immunomodulatory effects of MSCs in vivo are controversial and the underlying molecular mechanisms are not conclusive. In this study, we investigated the therapeutic potential of autologous bone marrow-derived MSCs on TA in a porcine model of femoral artery transplantation. MSCs or saline were injected into the soft tissue surrounding the arterial grafts immediately postanastomosis. Four weeks after transplantation, neointimal formation increased significantly in untreated allografts compared with the MSC-treated grafts as assessed by intravascular ultrasound (maximum luminal area stenosis: 40 ± 12% vs. 18 ± 6%, p < 0.001). Grafts harvested at 4 weeks showed dense perivascular lymphocyte infiltration accompanied by significant intimal hyperplasia in the untreated but not in the MSC-treated allografts. Serial angiographic examination showed that all of the untreated allografts became occluded at the 8th week whereas the majority of the MSC-treated grafts remained patent at the 12th week posttransplantation ( n = 12 each group, p < 0.001). Quantitative PCR analysis revealed that Foxp3 expression was comparable between the untreated and the MSC-treated groups. However, expression of interleukin-10 (IL-10), interferon-γ (IFN-γ), and indoleamine 2,3-dioxygenase (IDO) was increased significantly in the MSC-treated allografts compared with that in the allograft controls ( p = 0.021 for IL-10, p = 0.003 for IFN-γ, and p = 0.008 for IDO). In conclusion, local delivery of autologous MSCs alleviates TA by inducing allograft tolerance via enhanced expression of IL-10, IFN-γ, and IDO but not Foxp3-positive cells in the vessel wall. These results suggest that MSCs induce immune tolerance by activating the type 1 regulatory T-like cells.
Seventy-Two-Hour Preservation, Resuscitation, and Transplantation of an Isolated Rat Heart with High Partial Pressure Carbon Monoxide Gas (PCO = 400 hPa) and High Partial Pressure Carbon Dioxide (PCO2 = 100 hPa)
Authors: Hatayama Naoyuki , Yoshida Yu , Seki Kunihiro
Published: July 2012

The cardiac cavity of an isolated rat heart was filled with a Krebs-Henseleit (KH) solution, and the heart was hung in a high-pressure chamber. After the high-pressure chamber had been filled with a mixed gas (PCO = 400 hPa, PCO2 = 100 hPa, PO2 = 900 hPa, PHe = 5600 hPa) and preserved for 72 h, we performed a cervical ectopic heart transplantation on a recipient rat and resuscitated the preserved heart. This is the first incidence in the world of a mammalian organ having been successfully preserved and resuscitated after 72 h via a desiccation method.
Regulation of the Actin Cytoskeleton by Rho Kinase Controls Antigen Presentation by CD1d
Authors: Gallo Richard M. , Khan Masood A. , Shi Jianjian , Kapur Reuben , Wei Lei , Bailey Jennifer C. , Liu Jianyun , Brutkiewicz Randy R.
Published: July 2012

CD1d molecules are MHC class I-like molecules that present lipid Ags to NKT cells. Although we have previously shown that several different cell signaling molecules can play a role in the control of Ag presentation by CD1d, a defined mechanism by which a cell signaling pathway regulates CD1d function has been unclear. In the current study, we have found that the Rho kinases, Rho-associated, coiled-coil containing protein kinase (ROCK)1 and ROCK2, negatively regulate both human and mouse CD1d-mediated Ag presentation. Inhibition of ROCK pharmacologically, through specific ROCK1 and ROCK2 short hairpin RNA, or by using dendritic cells generated from ROCK1-deficient mice all resulted in enhanced CD1d-mediated Ag presentation compared with controls. ROCK regulates the actin cytoskeleton by phosphorylating LIM kinase, which, in turn, phosphorylates cofilin, prohibiting actin fiber depolymerization. Treatment of APCs with the actin filament depolymerizing agent, cytochalasin D, as well as knockdown of LIM kinase by short hairpin RNA, resulted in enhanced Ag presentation to NKT cells by CD1d, consistent with our ROCK inhibition data. Therefore, our overall results reveal a model whereby CD1d-mediated Ag presentation is negatively regulated by ROCK via its effects on the actin cytoskeleton.
CD3ζ-Chain Expression of Human T Lymphocytes Is Regulated by TNF via Src-like Adaptor Protein-Dependent Proteasomal Degradation
Authors: Érsek Barbara , Molnár Viktor , Balogh Andrea , Matkó János , Cope Andrew P. , Buzás Edit I. , Falus András , Nagy György
Published: July 2012

Decreased expression of the TCR ζ-chain has been reported in several autoimmune, inflammatory, and malignant diseases, suggesting that ζ-chain downregulation is common at sites of chronic inflammation. Although ζ-chain is critically important in T lymphocyte activation, the mechanism of the decreased ζ-chain expression is less clear. Src-like adaptor protein (SLAP) is a master regulator of T cell activation; previous data have reported that SLAP regulates immunoreceptor signaling. We have examined the mechanism and the functional consequences of CD3 ζ-chain downregulation. TNF treatment of human T lymphocytes (15–40 ng/ml) selectively downregulates CD3 ζ-chain expression in a dose-dependent manner (p < 0.05) and decreases activation-induced IL-2 expression (p < 0.01). Although blocking of the lysosomal compartment fails to restore TNF-induced CD3 ζ-chain downregulation, inhibition of the proteasome prevented the effect of TNF. Both SLAP expression and the colocalization of SLAP with CD3 ζ-chain was enhanced by TNF treatment (p < 0.05 and p < 0.01, respectively), whereas TNF-induced ζ-chain downregulation was inhibited by gene silencing of SLAP with small interfering RNA. SLAP levels of the CD4+ T lymphocytes isolated from patients with rheumatoid arthritis were more than 2-fold higher than that of the healthy donors’ (p < 0.05); moreover, TNF treatment did not alter the SLAP expression of the CD4+ cells of anti-TNF therapy-treated patients. Our present data suggest that TNF modulates T cell activation during inflammatory processes by regulating the amount of CD3 ζ-chain expression via a SLAP-dependent mechanism. These data provide evidence for SLAP-dependent regulation of CD3 ζ-chain in the fine control of TCR signaling.
Cyclophilin B Attenuates the Expression of TNF-α in Lipopolysaccharide-Stimulated Macrophages through the Induction of B Cell Lymphoma-3
Authors: Marcant Adeline , Denys Agnès , Melchior Aurélie , Martinez Pierre , Deligny Audrey , Carpentier Mathieu , Allain Fabrice
Published: July 2012

Extracellular cyclophilin A (CyPA) and CyPB have been well described as chemotactic factors for various leukocyte subsets, suggesting their contribution to inflammatory responses. Unlike CyPA, CyPB accumulates in extracellular matrixes, from which it is released by inflammatory proteases. Hence, we hypothesized that it could participate in tissue inflammation by regulating the activity of macrophages. In the current study, we confirmed that CyPB initiated in vitro migration of macrophages, but it did not induce production of proinflammatory cytokines. In contrast, pretreatment of macrophages with CyPB attenuated the expression of inflammatory mediators induced by LPS stimulation. The expression of TNF-α mRNA was strongly reduced after exposure to CyPB, but it was not accompanied by significant modification in LPS-induced activation of MAPK and NF-κB pathways. LPS activation of a reporter gene under the control of TNF-α gene promoter was also markedly decreased in cells treated with CyPB, suggesting a transcriptional mechanism of inhibition. Consistent with this hypothesis, we found that CyPB induced the expression of B cell lymphoma-3 (Bcl-3), which was accompanied by a decrease in the binding of NF-κB p65 to the TNF-α promoter. As expected, interfering with the expression of Bcl-3 restored cell responsiveness to LPS, thus confirming that CyPB acted by inhibiting initiation of TNF-α gene transcription. Finally, we found that CyPA was not efficient in attenuating the production of TNF-α from LPS-stimulated macrophages, which seemed to be due to a modest induction of Bcl-3 expression. Collectively, these findings suggest an unexpected role for CyPB in attenuation of the responses of proinflammatory macrophages.
Genetic Interdependence of Lyn and Negative Regulators of B Cell Receptor Signaling in Autoimmune Disease Development
Authors: Tsantikos Evelyn , Maxwell Mhairi J. , Kountouri Nicole , Harder Kenneth W. , Tarlinton David M. , Hibbs Margaret L.
Published: July 2012

Ab-mediated autoimmune disease is multifaceted and may involve many susceptibility loci. The majority of autoimmune patients are thought to have polymorphisms in a number of genes that interact in different combinations to contribute to disease pathogenesis. Studies in mice and humans have implicated the Lyn protein tyrosine kinase as a regulator of Ab-mediated autoimmune disease. To examine whether haploinsufficiency of Lyn gives rise to cellular and clinical manifestations of autoimmune disease, we evaluated the phenotype of Lyn+/− mice. We find that their B cell compartment is significantly perturbed, with reduced numbers of marginal zone and transitional stage 2 B cells, expansion of plasma cells, downregulation of surface IgM, and upregulation of costimulatory molecules. Biochemical studies show that Lyn+/− B cells have defects in negative regulation of signaling, whereas Lyn+/− mice develop IgG autoantibodies and glomerulonephritis with age. Because Lyn has a pivotal role in the activation of inhibitory phosphatases, we generated mice harboring double heterozygous loss-of-function mutations in Lyn and SHP-1 or Lyn and SHIP-1. Partial inactivation of SHP-1 or SHIP-1 amplifies the consequence of Lyn haploinsufficiency, leading to an accelerated development of autoantibodies and disease. Our data also reveal that the BALB/c background is protective against autoimmune-mediated glomerulonephritis, even in the face of high titer autoantibodies, whereas the C57BL/6 background is susceptible. This study demonstrates that Lyn is a haploinsufficient gene in autoimmune disease and importantly shows that quantitative genetic variation in Lyn-regulated pathways can mirror the complete loss of a single critical inhibitory molecule.
CD4+ T Cells Disarm or Delete Cytotoxic T Lymphocytes under IL-17–Polarizing Conditions
Authors: Tsai Jy-Ping , Lee Meng-Hua , Hsu Shu-Ching , Chen Mei-Yu , Liu Shih-Jen , Chang Joseph T. , Liao Chun-Ta , Cheng Ann-Joy , Chong Pele , Chu Ching-Liang , Shen Chia-Rui , Chen Hsin-Wei
Published: July 2012

Previous studies have shown that TGF-β acts cooperatively with IL-6 to elicit a high frequency of IL-17–secreting CD4+ T cells (termed Th17) and an elevated CD8+IL-17+ T cell population (termed Tc17). These CD8+ cells fail to behave like most cytotoxic T lymphocytes that express IFN-γ and granzyme B, but they exhibit a noncytotoxic phenotype. Although a significant increase in the number of these Tc17 cells was found in tumors, their role and interaction with other cell types remain unclear. In this study, we demonstrate that the presence of CD4+CD25− T cells, but not the CD4+CD25+ (regulatory T [Treg]) cell population, significantly reduced the elicitation of Tc17 cells, possibly as a result of the induction of apoptotic signals. Importantly, these signals may be derived from soluble mediators, and the addition of anti–IL-2 restored the reduction of Tc17 cells in the presence of CD4+CD25− T cells. Finally, the elicited Tc17 and Treg cells exhibited a close association in patients with head and neck cancer, indicating that the surrounding Treg cells might maintain the survival of the Tc17 cells. Taken together, these results reveal an intriguing mechanism in which Tc17 cells are controlled by a finely tuned collaboration between the different types of CD4+ T cells in distinct tumor microenvironments.
Suppressor of Cytokine Signaling 1 DNA Administration Inhibits Inflammatory and Pathogenic Responses in Autoimmune Myocarditis
Authors: Tajiri Kazuko , Imanaka-Yoshida Kyoko , Matsubara Akihiro , Tsujimura Yusuke , Hiroe Michiaki , Naka Tetsuji , Shimojo Nobutake , Sakai Satoshi , Aonuma Kazutaka , Yasutomi Yasuhiro
Published: July 2012

Myocarditis and subsequent dilated cardiomyopathy are major causes of heart failure in young adults. Myocarditis in humans is highly heterogeneous in etiology. Recent studies have indicated that a subgroup of myocarditis patients may benefit from immune-targeted therapies, because autoimmunity plays an important role in myocarditis as well as contributing to the progression to cardiomyopathy and heart failure. Suppressor of cytokine signaling (SOCS) 1 plays a key role in the negative regulation of both TLR- and cytokine receptor-mediated signaling, which is involved in innate immunity and subsequent adaptive immunity. In this study, we investigated the therapeutic effect of SOCS1 DNA administration on experimental autoimmune myocarditis (EAM) in mice. EAM was induced by s.c. immunization with cardiac-specific peptides derived from α myosin H chain in BALB/c mice. In contrast to control myocarditis mice, SOCS1 DNA-injected mice were protected from development of EAM and heart failure. SOCS1 DNA administration was effective for reducing the activation of autoreactive CD4+ T cells by inhibition of the function of Ag-presenting dendritic cells. Our findings suggest that SOCS1 DNA administration has considerable therapeutic potential in individuals with autoimmune myocarditis and dilated cardiomyopathy.
IL-6 Amplifier, NF-κB–Triggered Positive Feedback for IL-6 Signaling, in Grafts Is Involved in Allogeneic Rejection Responses
Authors: Lee Jihye , Nakagiri Tomoyuki , Oto Takahiro , Harada Masaya , Morii Eiichi , Shintani Yasushi , Inoue Masayoshi , Iwakura Yoichiro , Miyoshi Shinichiro , Okumura Meinoshin , Hirano Toshio , Murakami Masaaki
Published: July 2012

The IL-6-amplifier first was discovered as a synergistic activation mechanism for NF-κB/STAT3 in type 1 collagen+ cells. This process is marked by the hyperinduction of chemokines and subsequent local inflammation that leads to autoimmune diseases. In this study, we show that IL-6 amplifier activation in grafts plays important roles in allogeneic graft rejection by using a tracheal heterotopic transplantation model that includes bronchiolitis obliterans, a pathological marker for chronic rejection. IL-6, epidermal growth factor, and IFN-γ all stimulate IL-6 amplifier activation, whereas CCL2, a chemotactic factor for Th1 cells, was one of the amplifier’s main targets. Interestingly, IFN-γ hyperinduced CCL2 in type 1 collagen+ cells via the IL-6 amplifier at least in vitro. In addition, we detected IL-6, CCL2, phospho-STAT3, and phospho-NF-κB in epithelial type 1 collagen+ cells of allogeneic tracheal grafts. These results show that IL-6 amplifier activation in grafts plays a critical role for graft rejection responses after allogeneic transplantation, including chronic rejection. From these results, we consider whether the IL-6 amplifier in grafts might be a valuable therapeutic target for the prevention of transplant rejection, including chronic rejection.
Enhanced Th17 Differentiation and Aggravated Arthritis in IEX-1–Deficient Mice by Mitochondrial Reactive Oxygen Species-Mediated Signaling
Authors: Zhi Liang , Ustyugova Irina V. , Chen Xinyuan , Zhang Qi , Wu Mei X.
Published: July 2012

CD4+ Th1 and Th17 cells both can cause autoimmune diseases, either alone or collaboratively, if left unchecked. However, what determines the dominant Th effector phenotype in a specific autoimmune disease remains poorly understood. Our present investigation shows that null mutation of IEX-1 promotes differentiation of Th17 cells but compromises the survival of Th1 cells. The differential effect gave rise to a greater number of Th17 cells, a higher level of IL-17 production, and more severe arthritis in IEX-1 knockout mice than in wild-type mice after immunizations with collagen. IEX-1 deficiency-facilitated Th17 cell differentiation was mediated by the increased formation of reactive oxygen species (ROS) at mitochondria following T cell activation, as suggested by marked inhibition of Th17 induction with ROS scavenger N-acetylcysteine or mitoquinone, a specific inhibitor for mitochondrial ROS production. Mitochondrial ROS augmented the expression of B cell-activating transcription factor, which may contribute to increased IL-17 production in the absence of IEX-1, in light of its importance in IL-17 transcription. The results demonstrate that mitochondrial ROS contribute significantly to the dominant Th effector phenotype in autoimmunity in addition to the cytokine milieu.
Abrogation of Src Homology Region 2 Domain-Containing Phosphatase 1 in Tumor-Specific T Cells Improves Efficacy of Adoptive Immunotherapy by Enhancing the Effector Function and Accumulation of Short-Lived Effector T Cells In Vivo
Authors: Stromnes Ingunn M. , Fowler Carla , Casamina Chanel C. , Georgopolos Christina M. , McAfee Megan S. , Schmitt Thomas M. , Tan Xiaoxia , Kim Tae-Don , Choi Inpyo , Blattman Joseph N. , Greenberg Philip D.
Published: July 2012

T cell expression of inhibitory proteins can be a critical component for the regulation of immunopathology owing to self-reactivity or potentially exuberant responses to pathogens, but it may also limit T cell responses to some malignancies, particularly if the tumor Ag being targeted is a self-protein. We found that the abrogation of Src homology region 2 domain-containing phosphatase-1 (SHP-1) in tumor-reactive CD8+ T cells improves the therapeutic outcome of adoptive immunotherapy in a mouse model of disseminated leukemia, with benefit observed in therapy employing transfer of CD8+ T cells alone or in the context of also providing supplemental IL-2. SHP-1−/− and SHP-1+/+ effector T cells were expanded in vitro for immunotherapy. Following transfer in vivo, the SHP-1−/− effector T cells exhibited enhanced short-term accumulation, followed by greater contraction, and they ultimately formed similar numbers of long-lived, functional memory cells. The increased therapeutic effectiveness of SHP-1−/− effector cells was also observed in recipients that expressed the tumor Ag as a self-antigen in the liver, without evidence of inducing autoimmune toxicity. SHP-1−/− effector CD8+ T cells expressed higher levels of eomesodermin, which correlated with enhanced lysis of tumor cells. Furthermore, reduction of SHP-1 expression in tumor-reactive effector T cells by retroviral transduction with vectors that express SHP-1–specific small interfering RNA, a translatable strategy, also exhibited enhanced antitumor activity in vivo. These studies suggest that abrogating SHP-1 in effector T cells may improve the efficacy of tumor elimination by T cell therapy without affecting the ability of the effector cells to persist and provide a long-term response.
Phospholipase C Activator m-3M3FBS Protects against Morbidity and Mortality Associated with Sepsis
Authors: Kim Sang Doo , Kim Hak Jung , Shim Jae Woong , Lee Ha Young , Lee Sung Kyun , Kwon Soonil , Jung Young Su , Baek Suk-Hwan , Park Joon Seong , Zabel Brian A. , Bae Yoe-Sik
Published: July 2012

Although phospholipase C (PLC) is a crucial enzyme required for effective signal transduction and leukocyte activation, the role of PLC in polymicrobial sepsis remains unclear. In this study, we show that the direct PLC activator m-3M3FBS treatment significantly attenuates vital organ inflammation, widespread immune cell apoptosis, and mortality in a mouse sepsis model induced by lethal cecal ligation and puncture challenge. Mechanistically, m-3M3FBS–dependent protection was largely abolished by pretreatment of mice with the PLC-selective inhibitor U-73122, thus confirming PLC agonism by m-3M3FBS in vivo. PLC activation enhanced the bactericidal activity and hydrogen peroxide production of mouse neutrophils, and it also enhanced the production of IFN-γ and IL-12 while inhibiting proseptic TNF-α and IL-1β production in cecal ligation and puncture mice. In a second model of sepsis, PLC activation also inhibited the production of TNF-α and IL-1β following systemic LPS challenge. In conclusion, we show that agonizing the central signal transducing enzyme PLC by m-3M3FBS can reverse the progression of toxic shock by triggering multiple protective downstream signaling pathways to maintain organ function, leukocyte survival, and to enhance microbial killing.
Cutting Edge: Brazilian Pemphigus Foliaceus Anti-Desmoglein 1 Autoantibodies Cross-React with Sand Fly Salivary LJM11 Antigen
Authors: Qian Ye , Jeong Joseph S. , Maldonado Mike , Valenzuela Jesus G. , Gomes Regis , Teixeira Clarissa , Evangelista Flor , Qaqish Bahjat , Aoki Valeria , Hans Gunter , Rivitti Evandro A. , Eaton Donald , Diaz Luis A.
Published: July 2012

The environmental factors that contribute to the development of autoimmune diseases are largely unknown. Endemic pemphigus foliaceus in humans, known as Fogo Selvagem (FS) in Brazil, is mediated by pathogenic IgG4 autoantibodies against desmoglein 1 (Dsg1). Clusters of FS overlap with those of leishmaniasis, a disease transmitted by sand fly (Lutzomyia longipalpis) bites. In this study, we show that salivary Ags from the sand fly, and specifically the LJM11 salivary protein, are recognized by FS Abs. Anti-Dsg1 monoclonal autoantibodies derived from FS patients also cross-react with LJM11. Mice immunized with LJM11 generate anti-Dsg1 Abs. Thus, insect bites may deliver salivary Ags that initiate a cross-reactive IgG4 Ab response in genetically susceptible individuals and lead to subsequent FS. Our findings establish a clear relationship between an environmental, noninfectious Ag and the development of potentially pathogenic autoantibodies in an autoimmune disease.
Chronic Exposure to Staphylococcal Superantigen Elicits a Systemic Inflammatory Disease Mimicking Lupus
Authors: Chowdhary Vaidehi R. , Tilahun Ashenafi Y. , Clark Chad R. , Grande Joseph P. , Rajagopalan Govindarajan
Published: July 2012

Chronic nasal and skin colonization with superantigen (SAg)-producing Staphylococcus aureus is well documented in humans. Given that trans-mucosal and trans-cutaneous absorption of SAgs can occur, we determined whether chronic exposure to small amounts of SAg per se could activate autoreactive CD4+ and CD8+ T cells and precipitate any autoimmune disease without further external autoantigenic stimulation. Because HLA class II molecules present SAg more efficiently than do mouse MHC class II molecules, HLA-DQ8 transgenic mice were implanted s.c. with mini-osmotic pumps capable of continuously delivering the SAg, staphylococcal enterotoxin B (total of 10 μg/mouse), or PBS over 4 wk. Chronic exposure to staphylococcal enterotoxin B resulted in a multisystem autoimmune inflammatory disease with features similar to systemic lupus erythematosus. The disease was characterized by mononuclear cell infiltration of lungs, liver, and kidneys, accompanied by the production of anti-nuclear Abs and deposition of immune complexes in the renal glomeruli. The inflammatory infiltrates in various organs predominantly consisted of CD4+ T cells bearing TCR Vβ8. The extent of immunopathology was markedly reduced in mice lacking CD4+ T cells and CD28, indicating that the disease is CD4+ T cell mediated and CD28 dependent. The absence of disease in STAT4-deficient, as well as IFN-γ–deficient, HLA-DQ8 mice suggested the pathogenic role of Th1-type cytokines, IL-12 and IFN-γ. In conclusion, our study suggests that chronic exposure to extremely small amounts of bacterial SAg could be an etiological factor for systemic lupus erythematosus.
Dynamics of Human Prothymocytes and Xenogeneic Thymopoiesis in Hematopoietic Stem Cell-Engrafted Nonobese Diabetic-SCID/IL-2rγnull Mice
Authors: Parietti Véronique , Nelson Elisabeth , Telliam Gladys , Le Noir Sandrine , Pla Marika , Delord Marc , Vanneaux Valérie , Mohtashami Mahmood , Macintyre Elizabeth A. , Gluckman Jean Claude , Asnafi Vahid , Zúñiga-Pflücker Juan-Carlos , Larghero Jérôme , Canque Bruno
Published: July 2012

To model the developmental pattern of human prothymocytes and thymopoiesis, we used NOD-scid/γc−/− mice grafted with human umbilical cord blood CD34+ hematopoietic progenitor cells (HPCs). Human prothymocytes developed in the murine bone marrow (BM) from multipotent CD34++CD38lolineage− HPCs to CD34++CD7+CD2- pro-T1 cells that progressed in a Notch-dependent manner to CD34+CD7++CD2+ pro-T2 cells, which migrated to the thymus. BM prothymocyte numbers peaked 1 mo after graft, dropped at mo 2, and persisted at low levels thereafter, with only a few CD34+CD7lo prothymocytes with limited T potential being detected by mo 5. As a consequence, thymopoiesis in this xenogeneic setting began by weeks 4–6, peaked at mo 3, and decreased thenceforth. Analyzing mice grafted at 2, 4 or 8, mo of age showed that in an “older” BM, prothymocyte differentiation was perturbed and resulted in CD34+CD7lo prothymocytes with limited T potential. Whereas the early drop in BM thymopoietic activity was related to a Notch-independent loss of T potential by CD34++CD38lolineage− HPCs, the later age-dependent production decline of prothymocytes was linked to a more complex mix of cell-intrinsic and microenvironmental defects. Accordingly, and contrasting with what was observed with umbilical cord blood HPCs, CD34+ HPCs from human adult BM displayed only marginal thymopoietic activity when grafted into young 2-mo-old NOD-scid/γc−/− mice. These data demonstrate that the developmental pattern of BM prothymocytes during human late fetal and early postnatal life can be reproduced in humanized mice, and they suggest that onset of human thymus involution relates to decreased colonization by prothymocytes.
Differential Requirement for CD70 and CD80/CD86 in Dendritic Cell-Mediated Activation of Tumor-Tolerized CD8 T Cells
Authors: Bak S. Peter , Barnkob Mike Stein , Bai Ailin , Higham Eileen M. , Wittrup K. Dane , Chen Jianzhu
Published: July 2012

A major obstacle to efficacious T cell-based cancer immunotherapy is the tolerizing-tumor microenvironment that rapidly inactivates tumor-infiltrating lymphocytes. In an autochthonous model of prostate cancer, we have previously shown that intratumoral injection of Ag-loaded dendritic cells (DCs) delays T cell tolerance induction as well as refunctionalizes already tolerized T cells in the tumor tissue. In this study, we have defined molecular interactions that mediate the effects of DCs. We show that pretreating Ag-loaded DCs with anti-CD70 Ab abolishes the ability of DCs to delay tumor-mediated T cell tolerance induction, whereas interfering with 4-1BBL, CD80, CD86, or both CD80 and CD86 had no significant effect. In contrast, CD80−/− or CD80−/−CD86−/− DCs failed to reactivate already tolerized T cells in the tumor tissue, whereas interfering with CD70 and 4-1BBL had no effect. Furthermore, despite a high level of programmed death 1 expression by tumor-infiltrating T cells and programmed death ligand 1 expression in the prostate, disrupting programmed death 1/programmed death ligand 1 interaction did not enhance T cell function in this model. These findings reveal dynamic requirements for costimulatory signals to overcome tumor-induced tolerance and have significant implications for developing more effective cancer immunotherapies.
Oxygen optodes as fast sensors for eddy correlation measurements in aquatic systems
Authors: Chipman Lindsay , Huettel Markus , Berg Peter , Meyer Volker , Klimant Ingo , Glud Ronnie , Wenzhoefer Frank
Published: July 2012

The aquatic eddy‐correlation technique can be used to noninvasively determine the oxygen exchange across the sediment‐water interface by analyzing the covariance of vertical flow velocity and oxygen concentration in a small measuring volume above the sea bed. The method requires fast sensors that can follow the rapid changes in flow and the oxygen transported by this flow to calculate the momentary advective flux driven by turbulent motions. In this article, we demonstrate that fast optical oxygen sensors, known as optodes, represent a good alternative to the traditional Clark‐type electrochemical microelectrodes for such measurements. Optodes have the advantage over microelectrodes of being insensitive to flow, less susceptible to signal drift, more durable under typical field conditions, less expensive, and repairable. Comparisons of the response times of optodes and microelectrodes to rapid oxygen changes showed that optimized optodes had the same response time (162 ± 66 ms) as the microelectrodes (160 ± 57 ms) and were fast enough to capture the oxygen fluctuations that are relevant for the eddy correlation flux calculations. Side by side comparisons of benthic O2 flux data collected with microelectrode‐based eddy correlation instruments and optode‐based eddy correlation instruments in freshwater and marine environments showed no significant differences between the measured fluxes. The optodes allow the development of more user‐friendly eddy correlation instruments that combine the advantages of non‐invasive measurements and integration of fluxes over a large footprint area, using a relatively rugged and less expensive sensor.
Underwater cryotrap‐membrane inlet system (CT‐MIS) for improved in situ analysis of gases
Authors: Gentz Torben , Schlüter Michael
Published: July 2012

Membrane inlet sensor techniques allow online, real‐time and in situ analyses of gases during the investigation of aquatic environments. Of specific interest for research and applied objectives are quantifications of gases like methane, higher hydrocarbons, carbon dioxide, nitrogen, volatile organic compounds, and pollutants. For these objectives, membrane inlet systems are coupled to optical or solid state sensors as well as mass spectrometers. Besides the gases of interest, large quantities of water vapor are passing through the membrane and are thus introduced into the sensor system. This downgrades the detection limit, affects the ionization efficiency of mass spectrometers, or could cause the condensation of water within infrared sensors. In this study, we describe a novel robust, low‐power cryotrap coupled to a membrane inlet system (CT‐MIS), which is suitable to be used in harsh environments, including underwater applications. The entire system is of small size and weight, is operated at −85°C, and requires an energy consumption of less than 10 Watt. By using the cryotrap, we are able to reduce water vapor in the analytical line by more than 98%. The detection limits for major and trace gases are considerably improved this way. For the trace gas methane (CH4), the detection limit was lowered from 100 to 16 nmol/L, which allows the measurement of methane in surface and bottom waters of coastal areas and lakes. In case of membrane failure, the CT‐MIS acts as a security system by shock‐freezing the water, thus blocking the capillary connection to the analyzer unit.
A new method for the estimation of sinking particle fluxes from measurements of the particle size distribution, average sinking velocity, and carbon content
Authors: McDonnell Andrew M. P. , Buesseler Ken O.
Published: July 2012

We describe a new method for estimating sinking particulate carbon fluxes at high spatial and temporal resolutions from measurements of the particle concentration size distribution taken with an in situ camera system, in this case an autonomous video plankton recorder (VPR). Paired measurements of polyacrylamide gel traps and the VPR result in depth‐ and size‐resolved parameterizations of the average sinking velocity, which enable the estimation of the flux size distribution from the concentration size distribution. Comparisons between the gel traps and the bulk carbon flux allows for the parameterization of the particle carbon content as a function of size. Together, these parameterizations permit the estimation of carbon fluxes from high‐resolution VPR surveys. This method enables greater spatial, vertical, and temporal resolution of flux measurements beyond what is possible with conventional sediment traps. We tested this method in the Sargasso Sea and found that it was capable of accurately reproducing the fluxes measured in sediment traps while offering substantial improvement in the accuracy of the estimated fluxes compared to previous global and regional parameterizations. Our results point to the importance of local calibrations of the average sinking velocity and particle carbon content when estimating carbon fluxes from measurement of the concentration size distribution. This method holds important oceanographic potential for elucidating regional or basin scale carbon flows and providing new mechanistic insights into the function of the biological pump.
Low volume quantification of dissolved organic carbon and dissolved nitrogen
Authors: Stubbins Aron , Dittmar Thorsten
Published: July 2012

A method for the quantification of dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) in aqueous samples of less than 600 µL is described. Analysis of low volumes is achieved through modification of a Shimadzu HTC TOC analyzer, which in its conventional configuration requires at least 7 mL sample. The modification allows manual injection of sample directly into the high temperature combustion column, bypassing much of the instrument's dead volume. Instrument performance (blank, precision, and response factor) in the low volume configuration was equal to that of the instrument in its native larger volume, auto‐analyzer configuration. The low volume modification is simple, low cost (less than €25) and reversible, taking a matter of minutes to install or remove. It allows routine high precision and accuracy measurement of DOC and TDN in cases where sample volume is limiting. When sample volumes are not limiting, the standard configuration of the Shimadzu is recommended due to the ability to use the auto‐analyzer and reduce the labor required per sample run.
Identifying spatial structure in phytoplankton communities using multi‐wavelength fluorescence spectral data and principal component analysis
Authors: Alexander Ryan , Gikuma‐Njuru Peter , Imberger Jörg
Published: July 2012

Rapid in situ measurements of some components of fluorescent spectra are now possible with submersible multi‐wavelength fluorometers, which implies that phytoplankton composition can be measured, at least implicitly, at a spatial resolution that allows many scales of patches to be resolved. We present a method for identifying the location of patches of distinct fluorescent groupings of phytoplankton by using principal component analysis (PCA) to process in situ spectral data. The processing method potentially allows retention of more information from the raw data than existing methods because it depends on fewer assumptions. Furthermore, it can be applied without the need for site‐specific calibration of the fluorometer. A series of idealized spectral data sets were used to explain the conceptual basis of the approach; the method was then applied to field spectral data sampled in Lake Victoria, Kenya. The results demonstrate that the main features of large sample sets of multi‐component spectral data can be summarized in a single graph that reveals the number of spectrally distinct groups of phytoplankton at the site, and allows information about the spatial structure of those different phytoplankton groups to be derived from subsequent analysis. In this way, fluorescent spectral data collected at high spatial resolution can be used to identify the locations of patches and facilitate targeted water sample collection from those locations to investigate the species diversity and distribution at a study site.
A comparison and correction of light intensity loggers to photosynthetically active radiation sensors
Authors: Long Matthew H. , Rheuban Jennie E. , Berg Peter , Zieman Joseph C.
Published: July 2012

Accurate light measurements are important in the analysis of photosynthetic systems. Many commercial instruments are available to determine light; however, the comparison of light estimates between studies is difficult due to the differences in sensor types and their calibrations. The measurement of underwater irradiance is also complicated by the scattering and attenuation of light due to interactions with particulates, molecules, and the bottom. Here, three sensor types are compared to evaluate the calibration of light intensity loggers to estimate photosynthetically active radiation (PAR). We present a simple calibration of light intensity loggers that agree within 3.8% to factory‐calibrated scalar PAR sensors under a wide range of environmental conditions. Under the same range of conditions, two identical factory‐calibrated PAR sensors showed a similar difference of 3.7%. The light intensity loggers were calibrated to a high‐quality PAR sensor using an exponential fit (r2 = 0.983) that accounts for differences in sensor types with respect to the angle of incoming light, scattering, and attenuation. The light loggers are small, robust, and simple to operate and install, and thus well‐suited for typical subsurface research. They are also useful for small‐scale measurements, when broad spatial coverage is needed, or in research requiring multiple sensors. Many studies have used these simple light intensity sensors to estimate PAR, yet their limitations and advantages in mimicking PAR have not been well defined previously. We present these small and user‐friendly loggers as an excellent alternative to more sophisticated scalar PAR sensors.
Quality of Trauma Surgery Podcasts in Credibility, Content, and Design
Authors: Merchant Asma Altaf Hussain , Shah Shayan Ali , Khursheed Asfia Arham , Ali Madeeha , Najam Sohaib , Farooq Rimsha , Bakhshi Saqib Kamran , Afzal Noreen , Rahim Komal Abdul , Shaikh Namra Qadeer , Haider Adil H.
Published: June 2024

Importance

There has been an emerging trend of podcast use in medical education over the past decade. With the increasing number of podcasts and learners’ interest in trauma surgery, it is vital to validate the quality of these podcasts.

Objective

To determine the quantity and quality of podcast episodes on trauma surgery.

Design, Setting, and Participants

This cross-sectional study identified trauma surgery podcasts published globally on the Google, Apple, and Spotify platforms as of May 31, 2023. An initial screening excluded podcasts not fulfilling the inclusion criteria (published as of May 31, 2023, and covering clinical knowledge or mentorship on general trauma surgery). A 10-item checklist developed from a modified Delphi consensus method was created to assess the podcasts’ credibility, content, and design as indicators of quality. Data extracted from each podcast episode included the duration, setting, host and guest credentials, and fulfillment of quality indicators. Data were analyzed on August 13, 2023.

Main Outcomes and Measures

The quality of each podcast was assessed using the 10-question checklist. A score of at least 80% in credibility (4 of 5 points), 75% in content (3 of 4 points), and 100% in design (1 of 1 point) was required to classify a podcast episode as having good quality.

Results

The initial search identified 204 podcasts on trauma surgery, of which 55 podcasts met the inclusion criteria. All 55 podcasts were published after 2014, with the majority hosted by males (85% [61 of 72 hosts]), based in the US (91% [50 of 55 podcasts]), and focused on clinical knowledge (80% [44 of 55 podcasts]). Podcast hosts and guests predominantly held a Doctor of Medicine degree (83% [113 of 136]), with 72% [46 of 64] of guests identifying as practicing trauma surgeons. While all 55 podcasts had excellent quality in terms of content and design, 20% (11 of 55) of podcasts were rated poorly on credibility. Credibility was further reduced for 60% (33 of 55) of podcasts because of nondisclosure of conflicts of interest.

Conclusions and Relevance

In this cross-sectional study of trauma surgery podcasts, most had good-quality content and design, but there was a lack of explicit conflict of interest disclosure. Content producers need to disclose their conflicts of interest appropriately to ensure credibility and improve the quality of their podcasts.
Healthy Lifestyle and the Likelihood of Becoming a Centenarian
Authors: Li Yaqi , Wang Kaiyue , Jigeer Guliyeerke , Jensen Gordon , Tucker Katherine L. , Lv Yuebin , Shi Xiaoming , Gao Xiang
Published: June 2024

Importance

Previous studies have reported that lifestyle factors were associated with life expectancy and/or mortality, but most of them studied the middle-aged or older age groups (aged ≥60 years), and few focused on people aged 80 years or older.

Objectives

To examine healthy lifestyle and the likelihood of becoming centenarians among people aged 80 years or older in China.

Design, Settings, and Participants

Using data from the Chinese Longitudinal Healthy Longevity Survey, a nationally representative and one of the largest prospective cohorts targeting people aged 80 years or older established in 1998, a community-based, prospective nested case-control study was performed. Data were analyzed from December 1, 2022, to April 15, 2024.

Exposures

A healthy lifestyle score for 100 (HLS-100, ranging from 0 to 6), including smoking, exercise, and dietary diversity, was constructed, with higher scores indicating potentially better health outcomes.

Main Outcomes and Measures

The primary outcome was survivorship to becoming a centenarian by 2018 (the end of follow-up). Information on sociodemographic characteristics, lifestyle factors, and other covariates was collected.

Results

The sample comprised 5222 individuals (61.7% women, mean [SD] age, 94.3 [3.3] years), including 1454 identified centenarians and 3768 controls (died before becoming centenarians) matched by age, sex, and year of entry. During a median follow-up of 5 (IQR, 3-7) years, 373 of 1486 individuals among the lowest HLS-100 (0-2) group and 276 of 851 individuals among the highest HLS-100 (5-6) group became centenarians. The adjusted odds ratio (AOR) comparing the highest vs the lowest HLS-100 groups was 1.61 (95% CI, 1.32-1.96; P < .001 for trend). An association was noted when we further treated centenarians with relatively healthy status as the outcome, as evaluated by self-reported chronic conditions, physical and cognitive function, and mental wellness (AOR, 1.54; 95% CI, 1.05-2.26). Similar results were observed in other sensitivity analyses.

Conclusions and Relevance

In this case-control study of Chinese older adults, adhering to a healthy lifestyle appears to be important even at late ages, suggesting that constructing strategic plans to improve lifestyle behaviors among all older adults may play a key role in promoting healthy aging and longevity.
Long-Term Stability of Benign Lobular Inner Nuclear Layer Proliferations
Authors: Shah Mital , Charbel Issa Peter
Published: June 2024

This case report describes an asymptomatic 55-year-old woman with unilateral benign lobular inner nuclear layer proliferations and hyperreflective lesions causing distortion of adjacent retinal layers.
Light‐Triggered PROTAC Nanoassemblies for Photodynamic IDO Proteolysis in Cancer Immunotherapy
Authors: Choi Jiwoong , Park Byeongmin , Park Jung Yeon , Shin Dongwon , Lee Sangmin , Yoon Hong Yeol , Kim Kwangmeyung , Kim Sun Hwa , Kim Yongju , Yang Yoosoo , Shim Man Kyu
Published: June 2024

While proteolysis‐targeting chimeras (PROTACs) hold great potential for persistently reprogramming the immunosuppressive tumor microenvironment via targeted protein degradation, precisely activating them in tumor tissues and preventing uncontrolled proteolysis at off‐target sites remain challenging. Herein, a light‐triggered PROTAC nanoassembly (LPN) for photodynamic indoleamine 2,3‐dioxygenase (IDO) proteolysis is reported. The LPN is derived from the self‐assembly of prodrug conjugates, which comprise a PROTAC, cathepsin B‐specific cleavable peptide linker, and photosensitizer, without any additional carrier materials. In colon tumor models, intravenously injected LPNs initially silence the activity of PROTACs and accumulate significantly in targeted tumor tissues due to an enhanced permeability and retention effect. Subsequently, the cancer biomarker cathepsin B begins to trigger the release of active PROTACs from the LPNs through enzymatic cleavage of the linkers. Upon light irradiation, tumor cells undergo immunogenic cell death induced by photodynamic therapy to promote the activation of effector T cells, while the continuous IDO degradation of PROTAC simultaneously blocks tryptophan metabolite‐regulated regulatory‐T‐cell‐mediated immunosuppression. Such LPN‐mediated combinatorial photodynamic IDO proteolysis effectively inhibits tumor growth, metastasis, and recurrence. Collectively, this study presents a promising nanomedicine, designed to synergize PROTACs with other immunotherapeutic modalities, for more effective and safer cancer immunotherapy.