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Human blood Vγ9Vδ2 T cells respond to signals from microbes and tumors and subsequently differentiate into professional antigen-presenting cells (γδ T-APCs) for induction of CD4 + and CD8 + T cell responses. γδ T-APCs readily take up and degrade exogenous soluble protein for peptide loading on MHC I, in a process termed antigen cross-presentation. The mechanisms underlying antigen cross-presentation are ill-defined, most notably in human dendritic cells (DCs), and no study has addressed this process in γδ T-APCs. Here we show that intracellular protein degradation and endosomal acidification were significantly delayed in γδ T-APCs compared with human monocyte-derived DCs (moDCs). Such conditions are known to favor antigen cross-presentation. In both γδ T-APCs and moDCs, internalized antigen was transported across insulin-regulated aminopeptidase (IRAP)–positive early and late endosomes; however, and in contrast to various human DC subsets, γδ T-APCs efficiently translocated soluble antigen into the cytosol for processing via the cytosolic proteasome-dependent cross-presentation pathway. Of note, γδ T-APCs cross-presented influenza antigen derived from virus-infected cells and from free virus particles. The robust cross-presentation capability appears to be a hallmark of γδ T-APCs and underscores their potential application in cellular immunotherapy.

We feel honored about the editorial in Mediastinum and highly welcome the title “Old wine in new bottles: C-reactive protein (CRP) is a promising tumor marker in thymic epithelial tumors” (1) written by Philipp Strobel on our recent findings (2).

γδ T cells comprise an evolutionarily conserved yet poorly understood subset of T cells. Numerous features place these unconventional lymphocytes at the branching point between antigen-presenting cells and natural killer cells of the innate immune system and major-histocompatibility-complex-restricted αβ T cells of the adaptive immune system. We propose a role for human Vγ9/Vδ2 T cells in the generation of monocyte-derived inflammatory dendritic cells during infection. Our model incorporates the peculiar innate-like specificity of Vγ9/Vδ2 T cells for the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), co-recruitment of monocytes and Vγ9/Vδ2 T cells to sites of infection, and their crosstalk, with profound consequences for the initiation of antigen-specific αβ T-cell responses. Vγ9/Vδ2 T cells act thus as a cellular switch between innate and adaptive defence mechanisms.

Background Acute myocardial infarction (AMI) is followed by post AMI cardiac remodelling, often leading to congestive heart failure. Homing of c-kit+ endothelial progenitor cells (EPC) has been thought to be the optimal source for regenerating infarcted myocardium. Methods Immune function of viable peripheral blood mononuclear cells (PBMC) was evaluated after co-culture with irradiated apoptotic PBMC (IA-PBMC) in vitro. Viable PBMC, IA-PBMC and culture supernatants (SN) thereof were obtained after 24 h. Reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay were utilized to quantify interleukin-8 (IL-8), vascular endothelial growth factor, matrix metalloproteinase-9 (MMP9) in PBMC, SN and SN exposed fibroblasts. Cell suspensions of viable- and IA-PBMC were infused in an experimental rat AMI model. Immunohistological analysis was performed to detect inflammatory and pro-angiogenic cells within 72 h post-infarction. Functional data and determination of infarction size were quantified by echocardiography and Elastica van Gieson staining. Results The IA-PBMC attenuated immune reactivity and resulted in secretion of pro-angiogenic IL-8 and MMP9 in vitro. Fibroblasts exposed to viable and IA-PBMC derived SN caused RNA increment of IL-8 and MMP9. AMI rats that were infused with IA-PBMC cell suspension evidenced enhanced homing of endothelial progenitor cells within 72 h as compared to control (medium alone, viable-PBMC). Echocardiography showed a significant reduction in infarction size and improvement in post AMI remodelling as evidenced by an attenuated loss of ejection fraction. Conclusion These data indicate that infusion of IA-PBMC cell suspension in experimental AMI circumvented inflammation, caused preferential homing of regenerative EPC and replaced infarcted myocardium.

Objective: Phosphate buffered saline (PBS) solutions are commonly used in laboratories for dilutions, washing cell suspensions, and rinsing, as well as additives to cell culture media. In the present study, we evaluated pro- and anti-inflammatory cytokine secretion of peripheral blood mononuclear cells (PBMCs) incubated in medium containing different PBS solutions. Methods: Human PBMCs were incubated in cell culture medium with different concentrations of PBS containing calcium (Ca ++ ) and magnesium (Mg ++ ) (+/+ PBS). Cells in medium alone or in suspensions containing PBS without Ca ++ and Mg ++ (–/– PBS) served as controls. Results: A dose-dependent increase of interleukin-1 receptor antagonist was found when PBMCs were cultured in medium supplemented with increasing concentrations of +/+ PBS. No significant differences were observed for interleukin-1s, interleukin-4, interleukin-10, or transforming growth factor s. Conclusions: The release of the antiinflammatory cytokine interleukin-1 receptor antagonist in addition to unchanged levels of pro-inflammatory mediators suggests an important modulatory mechanism of heightened extracellular calcium levels.

γδ T cells are implicated in host defense against microbes and tumors but their mode of function remains largely unresolved. Here, we have investigated the ability of activated human Vγ9Vδ2 + T cells (termed γδ T-APCs) to cross-present microbial and tumor antigens to CD8 + αβ T cells. Although this process is thought to be mediated best by DCs, adoptive transfer of ex vivo antigen-loaded, human DCs during immunotherapy of cancer patients has shown limited success. We report that γδ T-APCs take up and process soluble proteins and induce proliferation, target cell killing and cytokine production responses in antigen-experienced and naïve CD8 + αβ T cells. Induction of APC functions in Vγ9Vδ2 + T cells was accompanied by the up-regulation of costimulatory and MHC class I molecules. In contrast, the functional predominance of the immunoproteasome was a characteristic of γδ T cells irrespective of their state of activation. γδ T-APCs were more efficient in antigen cross-presentation than monocyte-derived DCs, which is in contrast to the strong induction of CD4 + αβ T cell responses by both types of APCs. Our study reveals unexpected properties of human γδ T-APCs in the induction of CD8 + αβ T effector cells, and justifies their further exploration in immunotherapy research.

The skin is constantly exposed to commensal microflora and pathogenic microbes. The stratum corneum of the outermost skin layer employs distinct tools such as harsh growth conditions and numerous antimicrobial peptides (AMPs) to discriminate between beneficial cutaneous microflora and harmful bacteria. How the skin deals with microbes that have gained access to the live part of the skin as a result of microinjuries is ill defined. In this study, we report that the chemokine CXCL14 is a broad-spectrum AMP with killing activity for cutaneous Gram-positive bacteria and Candida albicans as well as the Gram-negative enterobacterium Escherichia coli. Based on two separate bacteria-killing assays, CXCL14 compares favorably with other tested AMPs, including human β-defensin and the chemokine CCL20. Increased salt concentrations and skin-typical pH conditions did not abrogate its AMP function. This novel AMP is highly abundant in the epidermis and dermis of healthy human skin but is down-modulated under conditions of inflammation and disease. We propose that CXCL14 fights bacteria at the earliest stage of infection, well before the establishment of inflammation, and thus fulfills a unique role in antimicrobial immunity.

This paper analyzes constraints in terms of fuzzy-logical concepts for transforming families of fuzzy sets in order to guarantee linguistically interpretable solutions of fine-tuned or optimized fuzzy systems, and further, to make the whole process of fine tuning a well-posed problem. For this purpose, transformations for fuzzy sets are introduced which are constructed by means of the compositional rule of inference. It is investigated under which conditions on these transformations various characteristics of fuzzy partitions and fuzzy sets, like redundancy, convexity and topological aspects remain invariant. It is argued that further restrictions like the compactness of the set of admissible transformations are required in order to make the process of fine tuning well-posed. As main result it is demonstrated that compactness of this function space endowed with the uniform norm can be characterized in terms of purely fuzzy-logical concepts, that is, by means of fuzzy equivalence relations.

CXCL14 (BRAK) is an ill-described chemokine with unknown receptor selectivity. The human chemokine is constitutively expressed in epithelial tissues and is selective for dendritic cell precursors, indicating a possible function in the maintenance of epithelial DCs. Several studies have addressed the question of human CXCL14 expression in cancerous tissues; however, distribution in healthy tissues and, in particular, the cellular origin of this chemokine has not been thoroughly investigated. The expression pattern of murine CXCL14 is largely unknown. In agreement with the human chemokine, we demonstrated ubiquitous and constitutive expression of murine CXCL14 in various tissues, foremost in those of epithelial origin such as the skin and the gastrointestinal tract. In addition, we did not find any CXCL14 in lymphoid tissues. Interestingly and in contrast to humans, murine CXCL14 was strongly expressed in the lung. In the skin, CXCL14 was produced by keratinocytes and dermal macrophages in both mice and humans, whereas CXCL14-expressing mast cells could only be found in the human dermis. Therefore, despite the remarkable structural homology and the broad similarity in the tissue distribution of human and murine CXCL14, distinct differences point to diverse, species-specific needs for CXCL14 in epithelial immunity.

The pattern recognition receptor, RAGE, has been shown to be involved in adaptive immune responses but its role on the components of these responses is not well understood. We have studied the effects of a small molecule inhibitor of RAGE and the deletion of the receptor (RAGE−/− mice) on T cell responses involved in autoimmunity and allograft rejection. Syngeneic islet graft and islet allograft rejection was reduced in NOD and B6 mice treated with TTP488, a small molecule RAGE inhibitor (p < 0.001). RAGE−/− mice with streptozotocin-induced diabetes showed delayed rejection of islet allografts compared with wild type (WT) mice (p < 0.02). This response in vivo correlated with reduced proliferative responses of RAGE−/− T cells in MLRs and in WT T cells cultured with TTP488. Overall T cell proliferation following activation with anti-CD3 and anti-CD28 mAbs were similar in RAGE−/− and WT cells, but RAGE−/− T cells did not respond to costimulation with anti-CD28 mAb. Furthermore, culture supernatants from cultures with anti-CD3 and anti-CD28 mAbs showed higher levels of IL-10, IL-5, and TNF-α with RAGE−/− compared with WT T cells, and WT T cells showed reduced production of IFN-γ in the presence of TTP488, suggesting that RAGE may be important in the differentiation of T cell subjects. Indeed, by real-time PCR, we found higher levels of RAGE mRNA expression on clonal T cells activated under Th1 differentiating conditions. We conclude that activation of RAGE on T cells is involved in early events that lead to differentiation of Th1+ T cells.

Receptor for advanced glycation end products (RAGE) is an activation receptor triggered by inflammatory S100/calgranulins and high mobility group box-1 ligands. We have investigated the importance of RAGE on Ag priming of T cells in murine models in vivo. RAGE is inducibly up-regulated during T cell activation. Transfer of RAGE-deficient OT II T cells into OVA-immunized hosts resulted in reduced proliferative responses that were further diminished in RAGE-deficient recipients. Examination of RAGE-deficient dendritic cells did not reveal functional impairment in Ag presentation, maturation, or migratory capacities. However, RAGE-deficient T cells showed markedly impaired proliferative responses in vitro to nominal and alloantigens, in parallel with decreased production of IFN-γ and IL-2. These data indicate that RAGE expressed on T cells is required for efficient priming of T cells and elucidate critical roles for RAGE engagement during cognate dendritic cell-T cell interactions.

Background Systemic inflammation and apoptosis-specific immune activation play a major role in acute coronary syndromes (ACS) including acute myocardial infarction (AMI). The role of systemic and coronary obtained inflammatory plasma protein interleukin-1β precursor (IL-1βp), IL-1β-converting enzyme (ICE) and the apoptosis-specific caspase-cleaved cytokeratin-18 (ccCK-18) are not known in ACS. Materials and methods Plasma samples were obtained from stable angina (SA, n = 34), unstable angina (UA, n = 37) and patients with AMI (n = 39). Coronary blood was acquired by means of thrombectomy devices (X-sizer) in AMI patients. IL-1βp, ICE and ccCK-18 were determined by enzyme-linked immunosorbent assay (ELISA). Group comparisons were evaluated by parametric Tukey test. Multivariate logistic regression analysis was performed to determine predictive values of IL-1βp, ICE and ccCK-18 as compared to creatine kinase (CK) and troponin T (TnT) in order to relate these markers with the occurrence of myocardial damage. Results IL-1βp, ICE and ccCK-18 were identified to be significantly altered in the peripheral blood of patients suffering from AMI as compared to SA and UA. ROC curves were plotted and revealed that ccCK-18 is a novel sensitive marker for the detection of myocardial damage as compared to TnT or CK. (AUC ccCK-18 0·925, TnT AUC 0·62 and CK AUC 0·858.) Moreover, ICE and ccCK-18 were significantly increased at the site of coronary occlusion as compared to peripheral blood samples in AMI patients (both P

Dendritic cells (DCs) have long been recognized as key regulators of immune responses. However, the process of their recruitment to peripheral tissues and turnover during homeostasis remains largely unknown. The chemokine CXCL14 (BRAK) is constitutively expressed in skin and other epithelial tissues. Recently, the human chemokine was proposed to play a role in the homeostatic recruitment of macrophage and/or DC precursors toward the periphery, such as skin. Although so far no physiological function could be demonstrated for the murine CXCL14, it shows a remarkable homology to the human chemokine. In order to elucidate the in vivo role of CXCL14, we generated a mouse defective for this chemokine. We studied various components of the immune system with emphasis on monocytes/macrophages and DC/Langerhans cell (LC) populations in different tissues during steady state but did not find a significant difference between knockout (CXCL14(-)(/)(-)) and control mice. Functionally, LCs were able to become activated, to migrate out of skin, and to elicit a delayed type of hypersensitivity reaction. Overall, our data indicate that murine CXCL14 is dispensable for the homeostatic recruitment of antigen-presenting cells toward the periphery and for LC functionality.

In this review, we discuss the potential role of human gammadelta T cells in the control of adaptive immunity. Our latest findings emerged as a consequence of our working hypothesis, which predicts a close relationship between the migration control in leukocytes and their function in immune processes as diverse as hematopoiesis, initiation of adaptive immunity, and immune surveillance in peripheral tissues. Leukocyte migration control is defined by the combination of migration and adhesion receptors on their surface and the tissue distribution of the corresponding ligands. According to our hypothesis, leukocytes featuring migration receptors for homing to lymph nodes (LNs) will also display activities that preferentially take place within LNs. Following this line of thought, by showing LN-homing properties in a subset of human gammadelta T cells, we speculated that gammadelta T cells influence the initiation of T- and B-cell responses. Here, we summarize our recent data, showing that LN-homing gammadelta T cells have potent antigen-presenting cell characteristics. This unexpected finding is discussed with regards to microbial sensing by human gammadelta T cells and a possible role for these cells in anti-microbial immunity.

Background As a link between periodontal infections and an increased risk for vascular disease has been demonstrated, we assessed the ability of the Gram-negative periodontal pathogen Porphyromonas gingivalis to modulate properties of endothelial cells linked to inflammation and proatherogenic pathways. Methods and results Primary human aortic endothelial cells (HAEC) were infected with either P. gingivalis strain 381 or its non-invasive fimbriae-deficient mutant, DPG3, and incubated with U-937 monocytes, or Jurkat T cells. P. gingivalis -infected HAEC demonstrated significantly increased adhesion of immune cells compared to non-infected cells or those infected with DPG3. Heat-killed bacteria had no effect on mononuclear cell adhesion and P. gingivalis LPS had only a minimal effect. P. gingivalis infection significantly increased HAEC expression of VCAM-1, ICAM-1 and E-selectin, and enhanced production of IL-6, IL-8 and MCP-1. Conclusion These data demonstrate that live invasive P. gingivalis 381 elicits a pro-atherogenic response in HAEC.

Apoptosis of epithelial hepatocytes plays a pivotal role in acute as well as in chronic liver diseases. The cleavage of cytokeratin‐18 (CK‐18) by caspases is an early event in the apoptotic process. We therefore sought to investigate serum levels of CK‐18 and 20S proteasome in patients with liver cirrhosis, primary graft dysfunction (PDF), and acute liver failure (ALF), and in healthy volunteers. Enzyme‐linked immunosorbent assay (ELISA) was utilized to measure the concentration of M30, a fragment of CK‐18 cleaved at Asp396 (M30 neoantigen), and the concentration of 20S proteasome. Serum levels of the CK‐18 neoepitope M30 were significantly increased in ALF, primary graft dysfunction, and liver cirrhosis vs. healthy controls (1,993.6±124.7 U/L, 2,238.1±235.9 U/L, and 673.6±86.5 U/L vs. 66.8±29.1 U/L, respectively, P

This Research Topic entitled “History of Chemoattractant Research” collects a series of personal stories by numerous experts in the field of chemoattractant research. The individual contributions portray some key discoveries that helped to transform cell migration research into a global playing field within immunology (and beyond). Early progress had a profound effect on both academia and industry. Today, numerous academic laboratories are fully engaged in compiling a detailed road map describing the highly complex network of immune and tissue cells that respond to chemoattractants. Industrial research, on the other hand, centers on drugs that interfere with immune cell traffic in inflammatory diseases and cancer. By definition, chemoattractants include early (“classical”) chemoattractants of variable chemical composition and the large family of chemokines (chemotactic cytokines) that greatly outnumber the former compounds. As inferred from their name, all chemoattractants share the ability to induce cell migration (chemotaxis) via binding to a single class of G-protein-coupled receptors on target cells. Chemoattractant research was originally viewed as a specialty subject within cell biology. However, due to the increasing number of chemoattractants being discovered and their effect on every type of immune cells distributed throughout our body, it became quickly clear that chemoattractants constitute essential regulators of all aspects in immunity. Defects in the chemoattractant system are frequently associated with immunodeficiencies or autoimmunity/chronic diseases. We now know that the complexity of the chemokine and classical chemoattractant system perfectly mirrors the multitude of immune cells distinguished by lineage relationship, function, and tissue location.

We have read with great interest the work by Cui et al. (2015) and the letter to the Editor by Cappello et al. (2015). Historical knowledge of data acquisition and interpretation is paramount in the field of applied medical research. Our group was the first to describe increased HSP27 serum concentrations in patients with incipient and manifest COPD, in patients with lung cancer (Hacker et al. 2009; Ankersmit et al. 2012; Zimmermann et al. 2012) and patients with end-stage kidney disease (Lebherz-Eichinger et al. 2008). All these information originated from our research dating back to 2006. In this work, our group (a) investigated serum HSP27/60/70/90 content in patients that underwent coronary artery bypass grafting (CABG) surgery (Szerafin et al. 2008) and (b) identified COPD as an autoimmune disease (Lambers et al. 2009). How was this serum HSP27 insight generated in our laboratory? (a) We have collected serum samples of mild and severe COPD and these were stored at our biobank; (b) A Croatian research group had investigated for the first time the role of HSP27/70 in peripheral blood mononuclear cells (PBMC) derived from COPD patients (Lada et al., 2008); (c) Serendipity was in play since the right R&D HSP27/70 ELISA kit, as “left over” from a prior CABG study and was present in our fridge. All these coincidences led to granted patents stating that HSP27 has the potential to be a serum biomarker for early and manifest COPD and lung cancer (EP2141499, EP2652504). By interpreting the report by Cui et al. (2015) and its comment by Cappello et al. (2015), we want to allude to a recent publication by our research group (Zimmermann et al. 2014). It has to be accepted by the community that an ELISA detection kit for protein XY is sometimes not detecting protein XY (Mueller et al. 2012). In order to investigate this question, we have selected lung cancer patients with known increased serum HSP27 and evaluated five commercially available assays for HSP27 measurement with respect to their capabilities to differentiate non-small cell lung cancer (NSCLC) patients from healthy controls. The following HSP27 ELISA kits were utilized: RD Enzo Life Sciences, 0.823; Invitrogen, 0.780; Abcam 0.642; and MyBioSource, 0.523. From these results, we concluded that it was pure coincidence that we have unintentionally picked the “right” ELISA kit for our investigations in our study period (2007–2015). Abcam or MyBioSource commercial ELISA system would have completely failed to show any difference in our laboratory investigations. We conclude that the results of our clinical method comparison study revealed that commercially available HSP27 assays are not equally useful in detecting increased serum HSP27. By looking at Cui et al. (2015), we observed that a Stressgen Bioreagent HSP27 ELISA was utilized. Since we have not included this commercially available ELISA system in our study, we have difficulty in interpreting the presented results. Since our R&D HSP27 ELISA has repetitively corroborated our primary data set in COPD/lung cancer (>400 patients), it might be possible that Stressgen is detecting another moiety of HSP27 as compared to the R&D HSP27 system. As far as we are concerned, we believe that scientific statements, discussions and publications dealing with serum HSP27 and COPD/lung cancer are important when comparative methodologies are utilized. In conclusion, from an epistemological standpoint, it is of great interest to accept that non-hypothesis-driven “luck factor” has helped to gain a better understanding in COPD genesis. The future will show whether the scientific community will be able to present a biomarker to the public that is able to identify patients with risk to develop COPD or lung cancer. We are deeply convinced that only commercial interest will bring this important knowledge into the realm of clinics.

The localization of memory T cells to human skin is essential for long-term immune surveillance and the maintenance of barrier integrity. The expression of CCR8 during naive T cell activation is controlled by skin-specific factors derived from epidermal keratinocytes and not by resident dendritic cells. In this study, we show that the CCR8-inducing factors are heat stable and protease resistant and include the vitamin D3 metabolite 1α,25-dihydroxyvitamin D3 and PGE2. The effect of either metabolite alone on CCR8 expression was weak, whereas their combination resulted in robust CCR8 expression. Elevation of intracellular cAMP was essential because PGE2 could be substituted with the adenylyl cyclase agonist forskolin, and CCR8 expression was sensitive to protein kinase A inhibition. For effective induction, exposure of naive T cells to these epidermal factors needed to occur either prior to or during T cell activation even though CCR8 was only detected 4–5 d later in proliferating T cells. The importance of tissue environments in maintaining cellular immune surveillance networks within distinct healthy tissues provides a paradigm shift in adaptive immunity. Epidermal-derived vitamin D3 metabolites and PGs provide an essential cue for the localization of CCR8+ immune surveillance T cells within healthy human skin.

Threshold-based sampling schemes such send-on-delta, level-crossing with hysteresis and integrate-and-fire are studied as non-linear input-output systems that map Lipschitz continuous signals to event sequences with −1 and 1 entries. By arguing that stability requires an event sequence of alternating −1 and 1 entries to be close to the zero-sequence w.r.t. the given event metric, it is shown that stability is a metric problem. By introducing the transcription operator T, which cancels subsequent events of alternating signs, a necessary criterion for stability is derived. This criterion states that a stable event metric preserves boundedness of an input signal w.r.t to the uniform norm. As a byproduct of its proof a fundamental inequality is deduced that relates the operator T with Hermann Weyl's discrepancy norm and the uniform norm of the input signal.

The discovery of follicular B helper T (TFH) cells has its roots in the early 90s, the “childhood” of chemokine research that has since grown into an independent, global specialty within immunology. The class of chemoattractant proteins with shared structural features was named “chemokines,” and early work with non-chemokine (FMLP, C5a) and chemokine (IL-8/CXCL8) receptors revealed that chemokine receptors belong to the large family of G-protein-coupled receptors (GPCRs) distinguished by their prototypical seven-transmembrane protein architecture. The search for novel chemokines and their receptors greatly intensified during that time, because it became increasingly clear that this novel cytokine system is essential for controlling immune cell mobilization and tissue localization and, hence, for controlling the entirety of immune processes in health and disease. Molecular identification of chemokine receptors led to the identification of immune cells that responded to the corresponding chemokine ligands and allowed their tracking during acute and chronic immune responses. At the last count, the inventory of chemokine receptors that, together with adhesion receptors, make up the address codes on human immune cells includes 18 individual members recognizing one or multiple of a total of 45 chemokines. Further underscoring the complexity of the chemokine system, we also know of six atypical chemokine receptors, some of which control chemokine positioning and degradation. Since my earliest steps in research, I was fascinated by the cytokine network controlling the highly complex interactions between immune cells and their functions in immune defense. In fact, an ambitious project aimed at the molecular characterization of the elusive “antigen-specific T helper factors” tipped the balance in favor of carrying out my Ph.D. studies in the lab of Profs. D. G. Kilburn, R. C. Miller Jr., and R. A. J. Warren at the University of British Columbia in Vancouver. It was not the skiing in the Whistler Mountains nor the salmon fishing along the Sunshine Coast that did the job, as suggested by some of my colleagues at the Federal Institute of Technology in Zurich. Needless to say that the molecular identification of the T cell antigen receptor in 1984 brought our project to an immediate halt. Still, when the question about postdoc projects arose, I was fascinated by the new world of chemotactic cytokines (to be called “chemokines” a few years later) that I was introduced to by Prof. Marco Baggiolini, the director at the Theodor-Kocher Institute of the University of Bern. Therefore, upon arrival at the Theodor-Kocher Institute in 1989, I was determined to clone the receptor for NAF, the first chemokine with selectivity for neutrophils (now known as IL-8 or CXCL8 according to the systematic chemokine nomenclature). This young field of research turned out to be highly competitive, not least because of its translational potential. Unsurprisingly, we were beaten by two labs who reported the cloning of the CXCL8 receptors well before our own initiative had a chance to take off (1, 2). As a small consolation, we succeeded to be first in demonstrating that human neutrophils carried two types of CXCL8 receptors on their cell surface distinguished by their variable affinity for other CXCL8-related chemokines (3, 4). Still, our multipronged cloning efforts paid off and revealed numerous orphan GPCRs with similarity to the CXCL8 receptors. In a great team effort by many colleagues, including Marcel Loetscher, Daniel Legler, Patrick Schaerli, and Regula Stuber-Roos, together with the protein chemist Ian Clark-Lewis at the Biomedical Research Centre of the University of British Columbia (who sadly died in 2002), we were then able to “deorphanize” some of these novel GPCRs in the subsequent years. As part of our chemokine receptor cloning initiatives, Luca Barella, who was a Ph.D. student in my lab, identified and characterized an orphan GPCR, termed monocyte-derived receptor 15 (MDR15) (5), which turned out to be a structural variant of Burkitt’s lymphoma receptor 1 (BLR1) published several years ahead of us by Martin Lipp’s group in Berlin (6). In fact, we first heard about BLR1 during a conversation with Martin Lipp whom we met in July 1992 at the fifth International Congress on Cell Biology in Madrid. Based on the structural similarities to the chemokine receptors that were known at that time (CXCR1, CXCR2, CCR1, and CCR2), it was clear to us that MDR15/BLR1 must be a novel chemokine receptor. However, none of the known chemokines bound to it. Intriguingly, MDR15/BLR1 transcripts were primarily found to be present in the lymphocyte fraction of peripheral blood mononuclear cells, and most notably in chronic B leukemia cell lines, but not in cells characterized by the other known chemokine receptors. It took another 3 years to “deorphanize” MDR15/BLR1. While searching expressed sequence tag (EST) cDNA databanks, Daniel Legler, a Ph.D. student at that time, identified a novel chemokine, which we termed B cell-attracting chemokine 1 (BCA-1; now officially known as CXCL13) because of its efficacious chemoattractant activity for B cells (7). The mouse ortholog of BCA-1/CXCL13 was published by the group of Michael Gunn at UCSF within the same month (8). Importantly, Michael Gunn and our group found that BCA-1/CXCL13 was the selective chemokine ligand for mouse and human MDR15/BLR1 (now officially known as CXCR5), respectively. Of note, the highly selective expression of CXCL13 in secondary lymphoid tissues matched perfectly well the findings of Martin Lipp’s group about the importance of BLR1 in the localization of B cells within murine secondary lymphoid tissues (9). In addition to B cells, we noticed that a large fraction of CD4+ memory T cells present in tonsils expressed CXCR5. By contrast, CXCR5+ T cells were relatively scarce in peripheral blood of healthy individuals. We also found that its single ligand CXCL13 was discretely expressed in the follicular mantle zone but not in the paracortical T cell zone or high endothelial venules where the CCR7-specific chemokines CCL19 and CCL21 are present. Unlike CCL19/CCL21, it appeared that CXCL13 did not play a role in the recruitment of T cells (and B cells) into lymph nodes but instead controlled the segregation of lymphocytes between T cell and B cell compartments, as Michael Gunn’s group has shown for BLC in mice (10). Could it be that tonsillar CXCR5+ T cells corresponded to the elusive T helper cell subset postulated to control B cell responses to protein antigens? Indeed, tonsillar B cells produced large amounts of isotype-switched antibodies during co-culture with CXCR5+ T cells but not CXCR5- T cells. During a subsequent discussion with Martin Lipp, who contributed his CCR7-specific antibodies to our study, we found out that both of our groups had similar results and, therefore, we agreed to submit our findings as back-to-back manuscripts to the Journal of Experimental Medicine (11, 12). Together with the journal editors, we then decided to designate this novel T helper subset as TFH cells, which today is also known as “follicular helper T cells” and “B helper T cells” (Figure ​(Figure11). Figure 1 Follicular B helper T (TFH) cells. T cells reach the lymph node paracortical region (T zone) via high endothelial venules (blood) or afferent lymphatics (peripheral tissues) in response to the CCR7-specific chemokines CCL19 and CCL21. During contact with ... The separation of T helper cells into Th1 and Th2 cells was instrumental in delineating immune responses to distinct classes of pathogens, such as viruses and intracellular bacteria for Th1 cells and extracellular pathogens and allergens for Th2 cells. Following the fundamental dogma underscoring the inseparable relationship between tissue localization and immune cell function, we and Martin Lipp’s group jointly discovered TFH cells as a third distinct T helper cell subset, which was highlighted in a commentary by Charles Mackay (13). An avalanche of murine studies by numerous outstanding labs worldwide confirmed and extended our initial findings about the role played by TFH cells in humoral immunity. Thanks to their efforts, it is now clear that defects in their generation and/or function have a profound effect on antibody dependent immune responses. In fact, increased numbers of TFH cells are now known to be associated with B cell autoimmunity and lymphomas whereas defects in TFH cell generation cause severe humoral immunodeficiency [reviewed in Ref. (14)]. Finally, since the presence of CXCR5+ T cells in peripheral blood reflects ongoing humoral immune responses (15), CXCR5 may even serve as a unique and convenient biomarker for the evaluation of ongoing vaccination responses. Today, TFH cells have a firm place among an increasing number of T helper cell subsets distinguished by their characteristic migration and functional properties.

A novel approach for matching event sequences, that result from threshold-based sampling, is introduced. This approach relies on Hermann Weyl's discrepancy norm, which plays a central role in the context of stability analysis of threshold-based sampling. This metric is based on a maximal principle that evaluates intervals of maximal partial sums. It is shown that minimal length intervals of maximal discrepancy can be exploited, in order to efficiently cluster spikes by means of approximating step functions. In contrast to ordinary spikes, these spike clusters can not only be shifted, deleted or inserted, but also stretched and shrinked, which allows more flexibility in the matching process. A dynamic programming approach is applied in order to minimizing an energy functional of such deformation manipulations. Simulations based on integrate-and-fire sampling show its potential above all regarding robustness.

The frequency of CD4+ Foxp3+ regulatory T (Treg) cells is often significantly\ud increased in the blood of tumour-bearing mice and people with\ud cancer. Moreover, Treg cell frequencies are often higher in tumours compared\ud with blood and lymphoid organs. We wished to determine whether\ud certain chemokines expressed within the tumour mass selectively recruit\ud Treg cells, thereby contributing to their enrichment within the tumourinfiltrating\ud lymphocyte pool. To achieve this goal, the chemokine profile\ud of carcinogen-induced fibrosarcomas was determined, and the chemokine\ud receptor expression profiles of both CD4+ Foxp3\ud �\ud and CD4+ Foxp3+ T\ud cells were compared. These analyses revealed that the tumours are characterized\ud by expression of inflammatory chemokines (CCL2, CCL5, CCL7,\ud CCL8, CCL12, CXCL9, CXCL10 and CX3CL1), reflected by an enrichment\ud of activated Foxp3\ud �\ud and Foxp3+ T cells expressing T helper type 1-\ud associated chemokine receptors. Notably, we found that CXCR3+ T cells\ud were significantly enriched in the tumours although curiously we found\ud no evidence that CXCR3 was required for their recruitment. Instead,\ud CXCR3 marks a population of activated Foxp3\ud �\ud and Foxp3+ T cells,\ud which use multiple and overlapping ligand receptor pairs to guide their\ud migration to tumours. Collectively, these data indicate that enrichment of\ud Foxp3+ cells in tumours characterized by expression of inflammatory\ud chemokines, does not occur via a distinct chemokine axis, thus selective\ud chemokine blockade is unlikely to represent a meaningful therapeutic\ud strategy for preventing Treg cell accumulation in tumours.

In this paper, we present a view of kernels from a fuzzy set theoretical perspective. Indeed, it turns out that kernels which are positive-definite functions have to fulfill a consistency property given by the so-called T-transitivity of a fuzzy T-equivalence relation with respect to the triangular norm T. As a result, we introduce a triangular norm T cos which is characterized as being the greatest one for which all kernels mapping to the unit interval and having constant 1 in its diagonal are T cos -equivalences. Finally, some applied relevant aspects are discussed as a starting point for further research.

A subtype of activated human gammadelta T cells, termed Vdelta2+ T cells, has antigen-presentation features similar in potency and efficacy to those seen in dendritic cells. Comparable treatment of alphabeta T cells does not result in 'professional' antigen presenting cells (APCs). What is so special about Vdelta2+ T cells? How do they acquire these unexpected properties? Under what physiological conditions would such a bridge between innate and adaptive immunity come into play? In addition to discussing these questions, we introduce a model that correlates the expression of lymph node homing receptors in Vdelta2+ T cells with the involvement of this alternative type of APC in anti-microbial alphabeta T cell responses.

We report 2 cases of primary thymic adenocarcinoma with enteric differentiation. One carcinoma occurred in a 41-year-old man as a 7-cm-diameter cystic tumor and the other one in a 39-year-old woman as a 6-cm-diameter solid mass. Both tumors were located in the anterior mediastinum. Clinical staging did not reveal any extrathymic tumor. Histologically, the tumors were classified as adenocarcinoma, not otherwise specified, and a mucinous (colloid) carcinoma, respectively. Immunohistochemically, both tumors were positive for cytokeratin 20 (CK20), CDX2, and carcinoembryonic antigen, reflecting enteric differentiation. A review of the literature on 43 other cases of primary thymic adenocarcinomas suggested 11 further cases with enteric differentiation, as assessed by CK20 and/or CDX2 expression. We propose that thymic adenocarcinoma with enteric differentiation represents a novel subtype of thymic carcinoma. It is mostly of mucinous morphology and frequently associated with thymic cysts. The clinical outcome is variable. Recognition of primary thymic adenocarcinoma with enteric differentiation is helpful for the differentiation from metastatic disease, mainly from the gastrointestinal tract.

T-cell help for B cells is essential for high-affinity antibody responses and B-cell memory. Recently, the identity of a discrete follicular population of T cells that has a crucial role in this process has become clearer. Similar to primed CD4(+) T cells in the tonsils and memory CD4(+) T cells in the peripheral blood, this follicular population of T cells expresses CXC-chemokine receptor 5 (CXCR5). Owing to their distinct homing preferences and helper function, these T cells differ from T helper 1 and T helper 2 cells and have been denoted follicular B helper T cells. Here, we outline the central role of this subset in normal and pathological immune responses.

Human γδ T cells are considered to play a vital role in protective immunity through cytokine secretion and cytotoxic activity. We report that cells expressing the Vγ2Vδ2 + –T cell receptor (Vδ2 + T cells) also display principal characteristics of professional antigen-presenting cells such as dendritic cells. Thus, when activated, these cells efficiently processed and displayed antigens and provided co-stimulatory signals sufficient for strong induction of naïve αβ T cell proliferation and differentiation. We suggest that, upon microbial activation, Vδ2 + T cells participate in the induction of adaptive immune responses and that these cells may be a useful tool in vaccine development and immunotherapy.

Background Recently, circulating proteasome core particles (20S proteasome) have been suggested as a marker of cell damage and immunological activity in autoimmune diseases. Aberrant leucocyte activation and increased lymphocyte apoptosis with consecutive T-cell unresponsiveness is deemed to play a pivotal role in the sepsis syndrome. Moreover sepsis-induced muscle proteolysis mainly reflects ubiqutin proteasome-dependent protein degradation. We therefore sought to investigate serum levels of 20S proteasome in critical ill patients. Material and methods Case-control-study at a university hospital intensive care unit; 15 patients recruited within 24-48 h of diagnosis of sepsis, 13 trauma patients recruited within 24 h of admission to the ICU, a control group of 15 patients who underwent abdominal surgery, and 15 healthy volunteers. ELISA was used to measure the concentration of 20S proteasome in the sera of the patients and controls. Data are given as mean +/- SEM. Mann-Whitney U-test was used to calculate significance and a P-value of 0.05 was considered to be statistically significant. Results Marked increase of 20S proteasome was detected in the sera of septic patients (33 551 +/- 10 034 ng mL-1) as well as in trauma patients (29 669 +/- 5750 ng mL-1). In contrast, significantly lower concentrations were found in the abdominal surgery group (4661 +/- 1767 ng mL-1) and in the healthy control population (2157 +/- 273 ng mL-1). Conclusion Detection of 20S proteasome may represent a novel marker of immunological activity and muscle degradation in sepsis and trauma patients, and may be useful in monitoring the clinical effect of proteasome-inhibitors.

The Receptor for advanced glycation endproducts (RAGE) is a multi-ligand member of the immunoglobulin superfamily of cell surface molecules.1 Although first described as a receptor for AGEs, the products of nonenzymatic glycation and oxidation of proteins/lipids, later studies indicated that RAGE was also a signal transduction receptor for proinflammatory S100/calgranulins and amphoterin (or high mobility group box 1 [HMGB1]) and amyloid-β–peptide and β-sheet fibrils.2–4 Additionally, RAGE is a counter-receptor for Mac-1.5 These ligands may be generated and accumulate in diverse settings, such as diabetes, renal failure, neurodegeneration, autoimmunity/inflammatory milieux, and aging. RAGE ligands may synergize in tissues primed by genetic and/or environmental triggers to amplify perturbation. For example, in the case of Mac-1, it was demonstrated that in the presence of S100, the RAGE–Mac-1 interaction was augmented.5 Thus, RAGE ligands may be pieces of a scaffold that, together, magnify inflammatory mechanisms in the tissues. If left unchecked, RAGE-mediated sustained inflammation, coupled with failure of regenerative mechanisms, may lead to irreversible tissue injury.1 See page 1032 These concepts have been tested in rodent models of exaggerated neointimal expansion, the hallmark of atherosclerosis and restenosis, triggered by chronic hyperglycemia or acute physical stress. In apolipoprotein E–null mice rendered diabetic with streptozotocin, blockade of RAGE was accomplished using a soluble form of the receptor, soluble (s) RAGE, generated and purified from a baculovirus expression system as a decoy for the families of RAGE ligands. Administration of sRAGE to diabetic apolipoprotein E–null mice suppressed early acceleration of atherosclerosis as well as prevented progression of disease in diabetic mice with established atherosclerosis.6–7 In parallel, blockade of RAGE significantly decreased vascular expression of adhesion molecules, prothrombotic species such as tissue factor, and diminished antigen/activity of matrix metalloproteinases (MMPs). In addition, vascular levels of phosphorylated p38 MAP kinase and activated NF-κB, …

Antigen-driven T cell education and subsequent pathogen elimination present particular challenges for the immune system. Pathogens generally enter the body at peripheral sites such as the skin, gastrointestinal tract or lung, areas from which naïve T cells are largely excluded. Instead, naïve T cells constantly recirculate through secondary lymphoid organs, such as lymph nodes and Peyer's patches, in search for antigen brought to these locations by means of afferent lymphatic channels. Here, antigen-loaded dendritic cells present antigen-peptide-MHC complexes to clonotypic T cells and provide appropriate co-stimulatory signals for immune response initiation. As a result, short-lived effector T cells and long-lived memory T cells are generated that reach the peripheral tissue for participation in immune responses and immune surveillance. Effector and memory T cell relocation is non-random, due to tissue-specific "address codes" that allow proper tissue homing. This process involves adhesion molecules, including selectins, integrins, and corresponding vascular ligands as well as the large family of chemokines and their receptors. Here, we discuss the changes in chemokine receptor expression that occur during T cell activation and differentiation, and the ways in which these changes impact on the migration potential of naïve, effector, and memory T cells. We summarize our current understanding of T cell homing to the T zone and B cell follicles within secondary lymphoid tissues and highlight the two chemokine receptors CCR7 and CXCR5 that recognize chemokines constitutively present either in the T zone (CCR7 ligands CCL19/ELC and CCL21/SLC) or follicular compartment (CXCR5 ligand CXCL13/BCA-1). CCR7 is characteristic for naive and central memory T (T(CM)) cells whereas CXCR5 distinguishes follicular B helper T (T(FH)) cells. In addition, we further subdivide long-lived memory T cells into CCR7-negative effector memory T (T(EM)) cells and peripheral immune surveillance T (T(PS)) cells. The latter term designates the extraordinarily large subset of memory T cells with primary residence in normal (healthy) peripheral tissues. Our current understanding of T(PS) cell migration and function is highly fragmentary, but these cells are thought to provide immediate protection locally at the site of pathogen entry. Here, we propose that the tissue distribution of T(PS) cells is determined by a distinct set of chemokines and corresponding receptors that differs from those operating in secondary lymphoid tissues and inflammatory sites.

BACKGROUND: The alpha-Gal (Galalpha1,3-Galbeta1-4GlcNAc-R) epitope is the major xenoantigen causing hyperacute rejection of pig organs transplanted into primates. Porcine bioprostheses are utilized in cardiac surgery. However, premature degeneration of bioprostheses has limited utilization in younger patients and the immune response remains elusive. We sought to investigate whether a specific alpha-Gal immune response may play a role in this clinical scenario. MATERIALS AND METHODS: We investigated the presence of alpha-Gal-epitope on native and fixed porcine valves by means of confocal laser scanning microscope (CLSM). ELISA was utilized to evidence whether implantation of bioprostheses elicits augmentation of pre-existing cytotoxic anti alpha-Gal IgM antibodies within 10 days of surgery. Patients who underwent coronary artery bypass grafting (CABG) or mechanical valve replacement served as controls (each group, n = 12). To corroborate the clinical relevance of the alpha-Gal immune response in vivo, we studied serum obtained before and after implantation of bioprostheses and its potency to lyse porcine alpha-Gal-bearing PK15 cells. RESULTS: We found the immunogenic alpha-Gal-epitope on fibrocytes interspersed in the connective tissue of porcine valves as determined by vimentin/IB4 lectin binding. Moreover, patients who were provided with a bioprostheses had developed a significant increase of naturally occurring cytotoxic IgM antibodies directed towards alpha-Gal after surgical intervention as compared with control patients (P < 0.0001, respectively). Sera obtained from the patients after the implantation of bioprostheses demonstrated an increased cytotoxicity against alpha-Gal-bearing PK-15 cells as compared with preoperative sera (P < 0.001). The specificity of the cytotoxic effects was proven as soluble Galalpha1-3Galbeta1-4GlcNAc markedly inhibited cell death of alpha-Gal-bearing PK15 cells (P < 0.001). CONCLUSION: Our data suggest that implantation of bioprostheses in cardiac surgery induces a xenograft-specific immune response. Procedures diminishing the presence of alpha-Gal on bioprostheses, such as utilization of genetically manipulated alpha-Gal-deficient xenograft or pretreatment with alpha-Galactosidase, might diminuate the immune response against bioprostheses and extend durability.

Chemotactic migration of leucocytes largely depends on adhesive interaction with the substratum and recognition of a chemoattractant gradient. Both aspects, cell adhesion and chemotaxis, are regulated by members of the family of chemotactic cytokines (chemokines) comprising structurally related and secreted proteins of 67-127 amino acids in length. Breakdown in the control of leucocyte mobilisation contributes to chronic inflammatory diseases and, hence, interference with chemokine function is a promising approach for the development of novel anti-inflammatory medication. Chemokines target all types of leucocyte, including haematopoietic precursors, mature leucocytes of the innate immune system as well as naive, memory, and effector lymphocytes. The combinatorial diversity in responsiveness to chemokines ensures proper tissue distribution of distinct leucocyte subsets under normal and inflammatory/pathological conditions. Here, we discuss recent views on the role of chemokines in controlling tissue localisation of human memory T cells under steady state (non-inflamed) conditions. Emphasis is placed on a concept describing distinct subsets of memory T cells according to their primary residence in peripheral blood, secondary lymphoid tissues, or peripheral (extralymphoid) tissues.

Effective immune surveillance is essential for maintaining protection and homeostasis of peripheral tissues. However, mechanisms controlling memory T cell migration to peripheral tissues such as the skin are poorly understood. Here, we show that the majority of human T cells in healthy skin express the chemokine receptor CCR8 and respond to its selective ligand I-309/CCL1. These CCR8(+) T cells are absent in small intestine and colon tissue, and are extremely rare in peripheral blood, suggesting healthy skin as their physiological target site. Cutaneous CCR8(+) T cells are preactivated and secrete proinflammatory cytokines such as tumor necrosis factor-alpha and interferon-gamma, but lack markers of cytolytic T cells. Secretion of interleukin (IL)-4, IL-10, and transforming growth factor-beta was low to undetectable, arguing against a strict association of CCR8 expression with either T helper cell 2 or regulatory T cell subsets. Potential precursors of skin surveillance T cells in peripheral blood may correspond to the minor subset of CCR8(+)CD25(-) T cells. Importantly, CCL1 is constitutively expressed at strategic cutaneous locations, including dermal microvessels and epidermal antigen-presenting cells. For the first time, these findings define a chemokine system for homeostatic T cell traffic in normal human skin.

γδ T cells are inadequately defined both in terms of their migration potential and contribution to antimicrobial immunity. Here, we have examined the migration profile of human blood γδ T cells and related cell lines and correlated these findings with their distribution in secondary lymphoid tissues and their function in B-cell cocultures. We find that resting γδ T cells are characterized by an inflammatory migration program similar to cells of the innate immune system. However, T-cell receptor (TCR) triggering resulted in the rapid but transient induction of a lymph node (LN)-homing program, as evidenced by functional CCR7 expression and concomitant reduction in expression and function of CCR5 and, to a lesser degree, CCR2. Moreover, the LN-homing program was reflected by the presence of γδ T cells in gastrointestinal lymphoid tissues, notably in clusters within germinal centers of B-cell follicles. In line with these findings, VγVδ-TCR triggering resulted in prominent expression of essential B-cell costimulatory molecules, including CD40L, OX40, CD70, and ICOS. Furthermore, γδ T cells were shown to provide potent B-cell help during in vitro antibody production. Collectively, our findings agree with a role for γδ T cells in humoral immunity during the early phase of antimicrobial responses. (Blood. 2003; 102:3693-3701)

Induction therapy with polyclonal antithymocyte-globulin (ATG) is widely used in the prophylaxis and treatment of acute cardiac-allograft rejection. Thrombocytopenia, however, is a major side-effect of ATG therapy and its mechanisms are poorly understood. The influence of ATG on platelet aggregation was studied aggregometrically, expression of platelet surface activation antigens CD62P and CD63 was determined by flow cytometry analysis, and electron microscopy was utilized to determine thrombocyte morphology. Treatment of platelets with ATG markedly induced aggregation, whereas OKT3 or anti-IL-2R antibodies did not. Furthermore, platelets incubated with ATG featured an up-regulation of the surface activation markers CD62P and CD63, secretion of platelet-bound sCD40L (CD154) and increased signs of aggregation in electron microscopy analysis. The capacity of ATG to induce platelet aggregation was completely blocked by antibodies against the low-affinity Fc IgG receptor (CD32). Since blocking of CD32 abrogates platelet aggregation, we suggest that CD32 plays a crucial role in ATG-induced thrombocytopenia.

Diabetic nephropathy ensues from events involving earliest changes in the glomeruli and podocytes, followed by accumulation of extracellular matrix in the mesangium. Postulated mechanisms include roles for vascular endothelial growth factor (VEGF), produced by podocytes and contributing to enhanced excretion of urinary albumin and recruitment/activation of inflammatory cells, and transforming growth factor-beta (TGF-beta), elicited largely from mesangial cells and driving production of extracellular matrix. RAGE, a receptor for advanced glycation endproducts (AGEs) and S100/calgranulins, displays enhanced expression in podocytes of genetically diabetic db/db mice by age 13 weeks. RAGE-bearing podocytes express high levels of VEGF by this time, in parallel with enhanced recruitment of mononuclear phagocytes to the glomeruli; events prevented by blockade of RAGE. By age 27 weeks, soluble RAGE-treated db/db mice displayed diminished albuminuria and glomerulosclerosis, and improved renal function. Diabetic homozygous RAGE null mice failed to develop significantly increased mesangial matrix expansion or thickening of the glomerular basement membrane. We propose that activation of RAGE contributes to expression of VEGF and enhanced attraction/activation of inflammatory cells in the diabetic glomerulus, thereby setting the stage for mesangial activation and TGF-beta production; processes which converge to cause albuminuria and glomerulosclerosis.

Background— Previous studies suggested that blockade of RAGE in diabetic apolipoprotein (apo) E–null mice suppressed early acceleration of atherosclerosis. A critical test of the potential applicability of RAGE blockade to clinical settings was its ability to impact established vascular disease. In this study, we tested the hypothesis that RAGE contributed to lesion progression in established atherosclerosis in diabetic apoE-null mice. Methods and Results— Male apoE-null mice, age 6 weeks, were rendered diabetic with streptozotocin or treated with citrate buffer. At age 14 weeks, certain mice were killed or treated with once-daily murine soluble RAGE or albumin; all mice were killed at age 20 weeks. Compared with diabetic mice at age 14 weeks, albumin-treated animals displayed increased atherosclerotic lesion area and complexity. In diabetic mice treated with sRAGE from age 14 to 20 weeks, lesion area and complexity were significantly reduced and not statistically different from those observed in diabetic mice at age 14 weeks. In parallel, decreased parameters of inflammation and mononuclear phagocyte and smooth muscle cell activation were observed. Conclusions— RAGE contributes not only to accelerated lesion formation in diabetic apoE-null mice but also to lesion progression. Blockade of RAGE may be a novel strategy to stabilize atherosclerosis and vascular inflammation in established diabetes.

Mamdani (1975) controller was successfully used in many applications. One of its interpretations is that it uses a fuzzy relation as an approximation of the desirable input-output correspondence. We analyze mathematical properties of Mamdani controller and notice that it has lower computational complexity when compared to the residuum-based controller. However, we show that in standard situations, both these fuzzy controllers do not represent the rule base properly in the sense of finding a solution to the related system of fuzzy relational equations. First, we consider the premises and consequents as typical inputs and outputs, and we want their correspondence to be kept. Next, we require that each normal input produces an output that bears nontrivial information. These two conditions appear to be almost contradictory to the previous controllers. We suggest a generalization of Mamdani controller which allows us to satisfy these requirements. The theory and experiments suggest that it performs better without any change of rule base and without a substantial increase of complexity.

The receptor for advanced glycation end products (RAGE) and its proinflammatory S100/calgranulin ligands are enriched in joints of subjects with rheumatoid arthritis (RA) and amplify the immune/inflammatory response. In a model of inflammatory arthritis, blockade of RAGE in mice immunized and challenged with bovine type II collagen suppressed clinical and histologic evidence of arthritis, in parallel with diminished levels of TNF-alpha, IL-6, and matrix metalloproteinases (MMP) 3, 9 and 13 in affected tissues. Allelic variation within key domains of RAGE may influence these proinflammatory mechanisms, thereby predisposing individuals to heightened inflammatory responses. A polymorphism of the RAGE gene within the ligand-binding domain of the receptor has been identified, consisting of a glycine to serine change at position 82. Cells bearing the RAGE 82S allele displayed enhanced binding and cytokine/MMP generation following ligation by a prototypic S100/calgranulin compared with cells expressing the RAGE 82G allele. In human subjects, a case-control study demonstrated an increased prevalence of the 82S allele in patients with RA compared with control subjects. These data suggest that RAGE 82S upregulates the inflammatory response upon engagement of S100/calgranulins, and, thereby, may contribute to enhanced proinflammatory mechanisms in immune/inflammatory diseases.

The classical approaches in fuzzy control (Zadeh and Mamdani) deal with dense rule bases. When this is not the case, i.e. in sparse rule bases, one has to choose another method. Fuzzy rule interpolation [proposed first by Koczy and Hirota, Internat. J. Approx. Reason. 9 (1993) 197-225] offers a possibility to construct fuzzy controllers (KH controllers) under such conditions. The main result of this paper shows that the KH interpolation method is stable. It also contributes to the application oriented use of Balazs-Shepard interpolation operators investigated extensively by researchers in approximation theory. The numerical analysis aspect of the result contributes to the well-known problem of finding a stable interpolation method in the following sense. We would like to approximate a function that is only known at distinct points (e.g. where it can be measured). Since measurement errors cannot be eliminated in practice, it is a natural requirement that the interpolation method should be stable independently from the selection of measurement points. The classical interpolation methods generally do not fulfil this condition, only with certain strong restrictions concerning the measurement points. If we neglect the classical form of the approximating function (polynomial and trigonometrical), we can produce better behaving approximation. The KH controller approximating function, being a simple fractional function, fulfils the stability condition. This can also be interpreted as KH controllers are universal approximators in the space of continuous functions (with respect to, e.g., the supremum norm).

In this brief review of selected peer-reviewed literature on thymic minimally-invasive surgery (MIS) we sought to identify if there is a unique approach to thymic MIS on the European continent.