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Background & Aims Hypoxia inducible factors (HIFs) are a hallmark of inflammation and are key regulators of hepatic immunity and metabolism, yet their role in HBV replication is poorly defined. HBV replicates in hepatocytes within the liver, a naturally hypoxic organ, however most studies of viral replication are performed under conditions of atmospheric oxygen, where HIFs are inactive. We therefore investigated the role of HIFs in regulating HBV replication. Methods Using cell culture, animal models, human tissue and pharmacological agents inhibiting the HIF-prolyl hydroxylases, we investigated the impact of hypoxia on the HBV life cycle. Results Culturing liver cell-based model systems under low oxygen uncovered a new role for HIFs in binding HBV DNA and activating the basal core promoter, leading to increased pre-genomic RNA and de novo HBV particle secretion. The presence of hypoxia responsive elements among all primate members of the hepadnaviridae highlights an evolutionary conserved role for HIFs in regulating this virus family. Conclusions Identifying a role for this conserved oxygen sensor in regulating HBV transcription suggests that this virus has evolved to exploit the HIF signaling pathway to persist in the low oxygen environment of the liver. Our studies show the importance of considering oxygen availability when studying HBV-host interactions and provide innovative routes to better understand and target chronic HBV infection. Lay summary Viral replication in host cells is defined by the cellular microenvironment and one key factor is local oxygen tension. Hepatitis B virus (HBV) replicates in the liver, a naturally hypoxic organ. Hypoxia inducible factors (HIFs) are the major sensors of low oxygen; herein, we identify a new role for these factors in regulating HBV replication, revealing new therapeutic targets., Graphical abstract, Highlights • Primate hepadnaviridae encode conserved hypoxia response elements. • Hypoxia inducible factors bind HBV DNA and activate the basal core promoter. • Pharmacological stabilization of hypoxia inducible factors and low oxygen increases HBV transcription and particle genesis. • Knockdown studies show a role for both HIF-1α and HIF-2α in regulating HBV transcription.

A promising approach to tackle the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) could be small interfering (si)RNAs. So far it is unclear, which viral replication steps can be efficiently inhibited with siRNAs. Here, we report that siRNAs can target genomic RNA (gRNA) of SARS-CoV-2 after cell entry, and thereby terminate replication before start of transcription and prevent virus-induced cell death. Coronaviruses replicate via negative sense RNA intermediates using a unique discontinuous transcription process. As a result, each viral RNA contains identical sequences at the 5′ and 3′ end. Surprisingly, siRNAs were not active against intermediate negative sense transcripts. Targeting common sequences shared by all viral transcripts allowed simultaneous suppression of gRNA and subgenomic (sg)RNAs by a single siRNA. The most effective suppression of viral replication and spread, however, was achieved by siRNAs that targeted open reading frame 1 (ORF1) which only exists in gRNA. In contrast, siRNAs that targeted the common regions of transcripts were outcompeted by the highly abundant sgRNAs leading to an impaired antiviral efficacy. Verifying the translational relevance of these findings, we show that a chemically modified siRNA that targets a highly conserved region of ORF1, inhibited SARS-CoV-2 replication ex vivo in explants of the human lung. Our work encourages the development of siRNA-based therapies for COVID-19 and suggests that early therapy start, or prophylactic application, together with specifically targeting gRNA, might be key for high antiviral efficacy., Graphical Abstract Graphical AbstractExclusive targeting of SARS-CoV-2 genomic RNA enables most efficient suppression of viral replication and virus-induced cell death.

This paper explores how landscape research can contribute to our understanding of why integrated protected area concepts like biosphere reserves get less recognition than national parks. In this regard, we analysed policy documents and online communication of biosphere reserves and national parks, conducted qualitative interviews with conservation professionals and volunteers as well as participant observation in order to identify and compare narratives that guide the communication and perception of both protected area categories. The results show how national parks offer a clear interpretation of space by building on landscape stereotypes and creating landscape legibility and experience-ability through touristification. National Parks also experience conflicts about proper management and combine a variety of goals, often including regional development. Nevertheless, their narrative is unambiguous and powerful. Biosphere reserves, on the other hand, have an image problem that is essentially due to the difficulty of communicating their objectives. They confront the difficult task of creating a vision that combines development and conservation while integrating contrarious landscape stereotypes. We argue for a fundamental engagement with protected area narratives, as this improves understanding of protected areas’ transformative potential.

Acute viral respiratory tract infections (AVRIs) are a major burden on human health and global economy and amongst the top five causes of death worldwide resulting in an estimated 3.9 million lives lost every year. In addition, new emerging respiratory viruses regularly cause outbreaks such as SARS‐CoV‐1 in 2003, the "Swine flu" in 2009, or most importantly the ongoing SARS‐CoV‐2 pandemic, which intensely impact global health, social life, and economy. Despite the prevalence of AVRIs and an urgent need, no vaccines—except for influenza—or effective treatments were available at the beginning of the COVID‐19 pandemic. However, the innate RNAi pathway offers the ability to develop nucleic acid‐based antiviral drugs. siRNA sequences against conserved, essential regions of the viral genome can prevent viral replication. In addition, viral infection can be averted prophylactically by silencing host genes essential for host–viral interactions. Unfortunately, delivering siRNAs to their target cells and intracellular site of action remains the principle hurdle toward their therapeutic use. Currently, siRNA formulations and chemical modifications are evaluated for their delivery. This progress report discusses the selection of antiviral siRNA sequences, delivery techniques to the infection sites, and provides an overview of antiviral siRNAs against respiratory viruses., Pulmonary delivery of siRNA holds great promise for inhibiting respiratory virus replication particularly when antiviral drugs and vaccines are not yet available. This progress report discusses previous attempts of silencing respiratory viruses by highlighting the choice of target gene regions, the opportunities for the field of siRNA delivery and challenges in the development of inhalable siRNA formulations, particularly against SARS‐CoV‐2.

A promising approach to tackle the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) could be small interfering (si)RNAs. The proof of concept that SARS-CoV-2 can be inhibited with siRNAs, however, is missing. Here, we report that siRNAs can target genomic RNA (gRNA) of SARS-CoV-2 after cell entry, terminating replication before start of transcription and preventing cytopathic effects. Coronaviruses replicate via negative sense intermediate transcripts using a unique discontinuous transcription process. As a result, each viral RNA contains identical sequences at the 5’ and 3’ end. Surprisingly, siRNAs were not active against intermediate negative sense transcripts. Targeting sequences shared by different viral transcripts allowed simultaneous suppression of gRNA and subgenomic (sg)RNAs by a single siRNA. The most effective suppression of viral replication and spread, however, was achieved by siRNAs targeting open reading frame 1 (ORF1) which is solely part of gRNA. We propose two independent mechanisms for this: An increased accessibility of translational-active ORF1 before the start of transcription, as well as highly abundant sgRNAs out-competing siRNAs that target common sequences of transcripts. Our work encourages the development of siRNA-based therapies for COVID-19 and suggests that an early therapy start, together with targeting ORF1, might be key for high antiviral efficacy.

Several viral factors impact the natural course of hepatitis B virus (HBV) infection, the sensitivity of diagnostic tests, or treatment response to interferon-&alpha, and nucleos(t)ide analogues. These factors include the viral genotype and serotype but also mutations affecting the HBV surface antigen, basal core promoter/pre-core region, or reverse transcriptase. However, a comprehensive overview of the distribution of HBV variants between HBV genotypes or different geographical locations is lacking. To address this, we performed an in silico analysis of publicly available HBV full-length genome sequences. We found that not only the serotype frequency but also the majority of clinically relevant mutations are primarily associated with specific genotypes. Distinct mutations enriched in certain world regions are not explained by the local genotype distribution. Two HBV variants previously identified to confer resistance to the nucleotide analogue tenofovir in vitro were not identified, questioning their translational relevance. In summary, our work elucidates the differences in the clinical manifestation of HBV infection observed between genotypes and geographical locations and furthermore helps identify suitable diagnostic tests and therapies.

Hepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma (HCC) worldwide. The prolyl hydroxylase domain (PHD)-hypoxia inducible factor (HIF) pathway is a key mammalian oxygen sensing pathway and is frequently perturbed by pathological states including infection and inflammation. We discovered a significant upregulation of hypoxia regulated gene transcripts in patients with chronic hepatitis B (CHB) in the absence of liver cirrhosis. We used state-of-the-art in vitro and in vivo HBV infection models to evaluate a role for HBV infection and the viral regulatory protein HBx to drive HIF-signalling. HBx had no significant impact on HIF expression or associated transcriptional activity under normoxic or hypoxic conditions. Furthermore, we found no evidence of hypoxia gene expression in HBV de novo infection, HBV infected human liver chimeric mice or transgenic mice with integrated HBV genome. Collectively, our data show clear evidence of hypoxia gene induction in CHB that is not recapitulated in existing models for acute HBV infection, suggesting a role for inflammatory mediators in promoting hypoxia gene expression.

Hepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma (HCC) worldwide. The prolyl hydroxylase domain (PHD)-hypoxia inducible factor (HIF) pathway is a key mammalian oxygen sensing pathway and is frequently perturbed by pathological states including infection and inflammation. We discovered a significant upregulation of hypoxia regulated gene transcripts in patients with chronic hepatitis B (CHB) in the absence of liver cirrhosis. We used state-of-the-art in vitro and in vivo HBV infection models to evaluate a role for HBV infection and the viral regulatory protein HBx to drive HIF-signalling. HBx had no significant impact on HIF expression or associated transcriptional activity under normoxic or hypoxic conditions. Furthermore, we found no evidence of hypoxia gene expression in HBV de novo infection, HBV infected human liver chimeric mice or transgenic mice with integrated HBV genome. Collectively, our data show clear evidence of hypoxia gene induction in CHB that is not recapitulated in existing models for acute HBV infection, suggesting a role for inflammatory mediators in promoting hypoxia gene expression.

Landscape changes as a result of large-scale windthrows have sparked long-lasting conflicts about protected area management in Bavarian Forest National Park, Germany. We assess tourists, locals, and nature conservation professionals’ attitudes to these landscape changes. Methodologically we look at social media, local newspapers and the National Parks press releases and combine these findings with existing results from socio-scientific landscape research that we transfer to the field of ecosystem service assessments. We find that locals rate the value of landscape based on familiarity, while for tourists the connectivity to touristic landscape stereotypes is important. Nature conservation professionals assess the value of landscape based on biodiversity and especially value the appearance of rare species. As all groups use different measures to assess the value of a landscape, their evaluations of the changes to the national parks landscape differ clearly. We argue that when the value of cultural ecosystem services is assessed, the social context needs to be specified in order to improve the accuracy of any cultural ecosystem services assessment.

As the COVID-19 pandemic continues to spread, research on SARS-CoV-2 is also rapidly evolving and the number of associated manuscripts on preprint servers is soaring. To facilitate proteomic research, Zecha et al. present protein expression profiles of four model cell lines and investigate the response of Vero E6 cells to viral infection. Further, they evaluate the feasibility of proteomic analysis for SARS-CoV-2 diagnostics and critically discuss the merits of proteomic approaches in the context of the COVID-19 research., Graphical Abstract Highlights • In-depth proteomes of 4 SARS-CoV-2 cell line models (Vero E6, Calu-3, Caco-2, A549). • Proteomic evidence for thousands of Chlorocebus sabaeus proteins. • Proteomic response of Vero E6 cells to SARS-CoV-2 infection. • Synthetic peptides, spectral libraries, and targeted assays for SARS-CoV-2 proteins., As the COVID-19 pandemic continues to spread, thousands of scientists around the globe have changed research direction to understand better how the virus works and to find out how it may be tackled. The number of manuscripts on preprint servers is soaring and peer-reviewed publications using MS-based proteomics are beginning to emerge. To facilitate proteomic research on SARS-CoV-2, the virus that causes COVID-19, this report presents deep-scale proteomes (10,000 proteins; >130,000 peptides) of common cell line models, notably Vero E6, Calu-3, Caco-2, and ACE2-A549 that characterize their protein expression profiles including viral entry factors such as ACE2 or TMPRSS2. Using the 9 kDa protein SRP9 and the breast cancer oncogene BRCA1 as examples, we show how the proteome expression data can be used to refine the annotation of protein-coding regions of the African green monkey and the Vero cell line genomes. Monitoring changes of the proteome on viral infection revealed widespread expression changes including transcriptional regulators, protease inhibitors, and proteins involved in innate immunity. Based on a library of 98 stable-isotope labeled synthetic peptides representing 11 SARS-CoV-2 proteins, we developed PRM (parallel reaction monitoring) assays for nano-flow and micro-flow LC–MS/MS. We assessed the merits of these PRM assays using supernatants of virus-infected Vero E6 cells and challenged the assays by analyzing two diagnostic cohorts of 24 (+30) SARS-CoV-2 positive and 28 (+9) negative cases. In light of the results obtained and including recent publications or manuscripts on preprint servers, we critically discuss the merits of MS-based proteomics for SARS-CoV-2 research and testing.

Background & Aims Hepatitis B virus (HBV) infection persists because the virus-specific immune response is dysfunctional. Therapeutic vaccines might be used to end immune tolerance to the virus in patients with chronic infection, but these have not been effective in patients so far. In patients with chronic HBV infection, high levels of virus antigens might prevent induction of HBV-specific immune responses. We investigated whether knocking down expression levels of HBV antigens in liver might increase the efficacy of HBV vaccines in mice. Methods We performed studies with male C57BL/6 mice that persistently replicate HBV (genotype D, serotype ayw)—either from a transgene or after infection with an adeno-associated virus that transferred an overlength HBV genome—and expressed HB surface antigen at levels relevant to patients. Small hairpin or small interfering (si)RNAs against the common 3′-end of all HBV transcripts were used to knock down antigen expression in mouse hepatocytes. siRNAs were chemically stabilized and conjugated to N-acetylgalactosamine to increase liver uptake. Control mice were given either entecavir or non-HBV–specific siRNAs and vaccine components. Eight to 12 weeks later, mice were immunized twice with a mixture of adjuvanted HBV S and core antigen, followed by a modified Vaccinia virus Ankara vector to induce HBV-specific B- and T-cell responses. Serum and liver samples were collected and analyzed for HBV-specific immune responses, liver damage, and viral parameters. Results In both models of HBV infection, mice that express hepatocyte-specific small hairpin RNAs or that were given subcutaneous injections of siRNAs had reduced levels of HBV antigens, HBV replication, and viremia (1–3 log10 reduction) compared to mice given control RNAs. Vaccination induced production of HBV-neutralizing antibodies and increased numbers and functionality of HBV-specific, CD8+ T cells in mice with low, but not in mice with high, levels of HBV antigen. Mice with initially high titers of HBV and knockdown of HBV antigen expression, but not mice with reduced viremia after administration of entecavir, developed polyfunctional, HBV-specific CD8+ T cells, and HBV was eliminated. Conclusions In mice with high levels of HBV replication, knockdown of HBV antigen expression along with a therapeutic vaccination strategy, but not knockdown alone, increased numbers of effector T cells and eliminated the virus. These findings indicate that high titers of virus antigens reduce the efficacy of therapeutic vaccination. Anti-HBV siRNAs and therapeutic vaccines are each being tested in clinical trials—their combination might cure chronic HBV infection.

Grosschutzgebiete wie Nationalparks bergen landschaftsbezogene Konfliktpotenziale. Im Nationalpark Bayerischer Wald wird seit 30 Jahren Konfliktforschung betrieben. Im Zentrum stehen dabei Landschaftsveranderungen durch naturliche Storungsereignisse, insbesondere das grosflachige Absterben von Baumen nach Windwurf und Borkenkaferbefall. Unterschiedliche Deutungen landschaftlicher Veranderungen infolge dieser Ereignisse fuhrten zu langanhaltenden Konflikten. Aus naturschutzfachlicher Perspektive erscheinen die Storungsereignisse positiv, da sie die Struktur- und Artendiversitat der Waldlandschaft erhoht haben. Vielfach befurchtete negative Auswirkungen auf den Tourismus haben sich zudem nicht bestatigt: Weder das Urlaubserlebnis noch die Gasteankunfte wurden durch die entstandenen Totholzflachen beeintrachtigt, zu diesem Ergebnis kommen alle betrachteten Studien. Dieser Aspekt ist von besonderer Relevanz, da die Tourismusforderung als wichtigster Faktor fur die lokale Akzeptanz des Nationalparks identifiziert wurde. Untersuchungen zu Landschaftspraferenzen im Nationalpark zeigen zwar eine mehrheitliche Ablehnung von Totholz. Beitrage in den sozialen Medien offenbaren jedoch eine starke Wertschatzung und Idealisierung der naturlichen Storungsflachen im Nationalpark. Dabei spielt besonders die Deutung nachwachsender Baume eine zentrale Rolle.

Hepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma (HCC) worldwide. The prolyl hydroxylase domain (PHD)-hypoxia inducible factor (HIF) pathway is a key mammalian oxygen sensing pathway and is frequently perturbed by pathological states including infection and inflammation. We discovered a significant upregulation of hypoxia regulated gene transcripts in patients with chronic hepatitis B (CHB) in the absence of liver cirrhosis. We used state-of-the-art in vitro and in vivo HBV infection models to evaluate a role for HBV infection and the viral regulatory protein HBx to drive HIF-signalling. HBx had no significant impact on HIF expression or associated transcriptional activity under normoxic or hypoxic conditions. Furthermore, we found no evidence of hypoxia gene expression in HBV de novo infection, HBV infected human liver chimeric mice or transgenic mice with integrated HBV genome. Collectively, our data show clear evidence of hypoxia gene induction in CHB that is not recapitulated in existing models for acute HBV infection, suggesting a role for inflammatory mediators in promoting hypoxia gene expression.

High-capacity adenoviral vectors (HCAdVs) devoid of all coding genes are powerful tools to deliver large DNA cargos into cells. Here HCAdVs were designed to deliver a multiplexed complete CRISPR/Cas9 nuclease system or a complete pair of transcription activator-like effector nucleases (TALENs) directed against the hepatitis B virus (HBV) genome. HBV, which remains a serious global health burden, forms covalently closed circular DNA (cccDNA) as a persistent DNA species in infected cells. This cccDNA promotes the chronic carrier status, and it represents a major hurdle in the treatment of chronic HBV infection. To date, only one study demonstrated viral delivery of a CRISPR/Cas9 system and a single guide RNA (gRNA) directed against HBV by adeno-associated viral (AAV) vectors. The advancement of this study is the co-delivery of multiple gRNA expression cassettes along with the Cas9 expression cassette in one HCAdV. Treatment of HBV infection models resulted in a significant reduction of HBV antigen production and the introduction of mutations into the HBV genome. In the transduction experiments, the HBV genome, including the HBV cccDNA, was degraded by the CRISPR/Cas9 system. In contrast, the combination of two parts of a TALEN pair in one vector could not be proven to yield an active system. In conclusion, we successfully delivered the CRISPR/Cas9 system containing three gRNAs using HCAdV, and we demonstrated its antiviral effect. Keywords: chronic HBV infection, multiplexed CRISPR/Cas9, high-capacity adenovirus, cccDNA degradation

Highlights • Many emerging or known, chronic viral diseases are caused by enveloped viruses. • The review discusses research driven development of antivirals that became recently available or are in clinical evaluation. • The main focus is on antiviral strategies with a broader therapeutic range, and on novel immune based therapeutics. • Broad-spectrum antivirals will help to react faster to newly emerging viral diseases. • Targeting immune cells against infected cells can restore immune responses in chronic infections., Enveloped viruses pose an important health threat because most of the persistent and many emerging viruses are enveloped. In particular, newly emerging viruses create a need to develop broad-spectrum antivirals, which usually are obtained by targeting host cell factors. Persistent viruses have developed efficient strategies to escape host immune control, and treatment options are limited. Targeting host cell factors essential for virus persistence, or immune-based therapies provide alternative approaches. In this review, we therefore focus on recent developments to generate antivirals targeting host cell factors or immune-based therapeutic approaches to fight infections with enveloped viruses.

Hepatitis B virus (HBV) infection is a global health threat with 240 million chronic carriers at high risk to develop hepatocellular carcinoma. Current antiviral treatment can efficiently control viral replication and reduce liver inflammation, but is still quite far from achieving a cure. Significant progress has been made in understanding the virus life cycle and virus-host interaction in the past few years. With identification of the HBV receptor, cell-culture infection systems have become available that allow drug screening and establishing a pipeline of potential antivirals targeting either viral or host factors. Most of the candidate antivirals summarized in this review are still in preclinical development, but some have already entered or are about to enter early clinical trials.

International audience; BACKGROUND & AIMS: Viral clearance involves immune cell cytolysis of infected cells. However, studies of hepatitis B virus (HBV) infection in chimpanzees have indicated that cytokines released by T cells also can promote viral clearance via noncytolytic processes. We investigated the noncytolytic mechanisms by which T cells eliminate HBV from infected hepatocytes. METHODS: We performed a cytokine enzyme-linked immunosorbent assay of serum samples from patients with acute and chronic hepatitis B. Liver biopsy specimens were analyzed by in situ hybridization. HepG2-H1.3 cells, HBV-infected HepaRG cells, and primary human hepatocytes were incubated with interferon-gamma (IFNgamma) or tumor necrosis factor-alpha (TNF-alpha), or co-cultured with T cells. We measured markers of HBV replication, including the covalently closed circular DNA (cccDNA). RESULTS: Levels of IFNgamma and TNF-alpha were increased in serum samples from patients with acute vs chronic hepatitis B and controls. In human hepatocytes with stably replicating HBV, as well as in HBV-infected primary human hepatocytes or HepaRG cells, IFNgamma and TNF-alpha each induced deamination of cccDNA and interfered with its stability; their effects were additive. HBV-specific T cells, through secretion of IFNgamma and TNF-alpha, inhibited HBV replication and reduced cccDNA in infected cells without the direct contact required for cytolysis. Blocking IFNgamma and TNF-alpha after T-cell stimulation prevented the loss of cccDNA. Deprivation of cccDNA required activation of nuclear APOBEC3 deaminases by the cytokines. In liver biopsy specimens from patients with acute hepatitis B, but not chronic hepatitis B or controls, hepatocytes expressed APOBEC3A and APOBEC3B. CONCLUSIONS: IFNgamma and TNF-alpha, produced by T cells, reduce levels of HBV cccDNA in hepatocytes by inducing deamination and subsequent cccDNA decay

Gene therapy has become an accepted concept for the treatment of a variety of different diseases. In contrast to preclinical models, subjects enrolled in clinical trials, including gene therapy, possess a history of infection with microbes that may influence its safety and efficacy. Especially, viruses that establish chronic infections in the liver, one of the main targets for in vivo gene therapy, raise important concerns. Among them is the hepatitis B virus (HBV), which has chronically infected more than 350 million people worldwide. Here, we investigated the effect of HBV on adeno-associated viral (AAV) vectors, the most frequently applied gene transfer vehicles for in vivo gene therapy. Unexpectedly, we found that HBV greatly improved AAV transduction in cells replicating HBV and identified HBV protein x (HBx) as a key factor. Whereas HBV-positive and -negative cells were indistinguishable with respect to cell-entry efficiency, significantly higher numbers of AAV vector genomes were successfully delivered to the nucleus in the presence of HBV. The HBV-promoting effect was abolished by inhibitors of phosphatidylinositol 3-kinase (PI3K). PI3K was required for efficient trafficking of AAV to the nucleus and was enhanced in HBV-replicating cells and upon HBx expression. Enhancement of AAV transduction was confirmed in vivo using HBV transgenic mice and could successfully be applied to inhibit HBV progeny release. Conclusion: Our results demonstrate that acute, as well as chronic, infections with unrelated viruses change the intracellular milieu, thereby likely influencing gene therapy outcomes. In the case of HBV, HBx-mediated enhancement of AAV transduction is an advantage that could be exploited for development of novel treatments of HBV infection. (Hepatology 2014;59:2110-2120)

The endocannabinoid system has been shown to mediate beneficial effects on gastrointestinal inflammation via cannabinoid receptors 1 (CB1) and 2 (CB2). These receptors have also been reported to activate the MAP kinases p38 and c-Jun NH2-terminal kinase (JNK), which are involved in early acinar events leading to acute pancreatitis and induction of proinflammatory cytokines. Our aim was to examine the role of cannabinoid receptor activation in an experimental model of acute pancreatitis and the potential involvement of MAP kinases. Cerulein pancreatitis was induced in wild-type, CB1−/−, and MK2−/− mice pretreated with selective cannabinoid receptor agonists or antagonists. Severity of pancreatitis was determined by serum amylase and IL-6 levels, intracellular activation of pancreatic trypsinogen, lung myeloperoxidase activity, pancreatic edema, and histological examinations. Pancreatic lysates were investigated by Western blotting using phospho-specific antibodies against p38 and JNK. Quantitative PCR data, Western blotting experiments, and immunohistochemistry clearly show that CB1 and CB2 are expressed in mouse pancreatic acini. During acute pancreatitis, an upregulation especially of CB2 on apoptotic cells occurred. The unselective CB1/CB2 agonist HU210 ameliorated pancreatitis in wild-type and CB1−/− mice, indicating that this effect is mediated by CB2. Furthermore, blockade of CB2, not CB1, with selective antagonists engraved pathology. Stimulation with a selective CB2 agonist attenuated acute pancreatitis and an increased activation of p38 was observed in the acini. With use of MK2−/− mice, it could be demonstrated that this attenuation is dependent on MK2. Hence, using the MK2−/− mouse model we reveal a novel CB2-activated and MAP kinase-dependent pathway that modulates cytokine expression and reduces pancreatic injury and affiliated complications.

Einleitung: Das Endocannabinoid-System (ECS) besteht aus Rezeptoren (CB1 und CB2), endogenen Liganden (Lipide) und Endocannabinoid-degradierenden Mechanismen. Die am besten charakterisierten endogenen Cannabinoide sind Anandamid (AEA) und 2-Arachidonoyl-Glycerol (2-AG). Beide wirken als Agonisten an CB1 und CB2 Rezeptoren. In mehreren Studien wurde berichtet, dass die Aktivierung des ECS anti-inflammatorische Wirkungen vermittelt. Ziele: Das Ziel unserer Studie war es, die mogliche anti-inflammatorische Rolle von CB2-Rezeptoren in einem akuten Pankreatitismodell zu untersuchen. Methoden: Eine akute Pankreatitis wurde durch 6 stundliche intraperitoneale Injektionen von Caerulein (50µg/kg KG) in C57/bl Mausen induziert. JWH133, ein synthetischer, spezifischer CB2 Agonist und AM630, ein selektiver CB2 Antagonist wurden einmalig, 30min vor der ersten Caerulein-Injektion intraperitoneal verabreicht. Das Ausmas der Pankreatitis wurde durch Messung der Serumamylasespiegel, der Trypsinaktivitat im Pankreashomogenat, der MPO-Aktivitat der Lunge sowie durch die Histologie und Ausmas des Gewebodems bestimmt. Zusatzlich wurden die Lysate der Pankreata mittels Western Blotting und spezifischer Antikorper gegen aktivierte Kinasen (p38 und JNK) untersucht. Ergebnisse: Eine einmalige prophylaktische Gabe des CB2 Agonisten JWH133 reduzierte geringfugig das Ausmas der Pankreatitis. JWH133 hatte hingegen keinen Einfluss auf die Serumamylasespiegel und die Trypsinaktivierung im Pankreas. Die Vorbehandlung mit AM630 ergab abgesehen von einer Reduktion der MPO-Aktivierung in der Lunge keine signifikanten Unterschiede zu den Kontrolltieren. Sowohl JWH133 als auch AM630 zeigten keine signifikanten Unterschiede in der Aktivierung der p38- und JNK. Schlussfolgerung: Cannabinoide wirken protektiv im Modell der akuten Pankreatitis. Der CB2 Rezeptor ist an den protektiven Mechanismen beteiligt, scheint hierbei aber eine untergeordnete Rolle zu spielen. Weiterfuhrende Studien mit CB1/CB2 Agonisten, sind notwendig um die Bedeutung der einzelnen Rezeptoren und der beteiligten Signalwege naher zu charakterisieren.

Goods made in Germany can not compete primarily through low prices. German production input costs, particularly the expense of labor, are too high for that. Over the last few decades, German manufacturers have successfully compensated for their disadvantages in production costs by focusing on advanced technology, high quality, and specialized products tailored to customer needs. However, recently an additional strategy has been added to this portfolio — to package together manufactured goods and complementary services (Reichwald and Moslein 1995, Ganz and Stanke 1996, Homburg and Garbe 1996). The basic idea is that the complementary services add value to the goods and distinguish them in the market, raising the package above the intense global price pressures that would otherwise apply (Simon 1993). If enterprises succeed in melding goods and services into a combination which customers can order like a service, disadvantages based solely on manufacturing costs do not become so relevant.

Im ostdeutschen Werkzeugmaschinenbau sind Ende 1991 noch ca. 24.000 Beschäftigte tätig gewesen. Auf mittlere Sicht werden nicht mehr als 15.000 Menschen Beschäftigung finden. Allerdings nur, wenn es gelingt, die Produktion zu stabilisieren, d.h. wenn Produkte angeboten werden können, die den neuen Marktanforderungen entsprechen. Die Voraussetzungen hierfür sind in den Unternehmen des ostdeutschen Werkzeugmaschinenbaus noch gegeben: Der Personalabbau hat bei ihnen nicht zum Verlust der Fähigkeit geführt, auf der Grundlage eigener Entwicklungen Produktinnovationen auf den Markt zu bringen. Wie die Analysen zeigten, wurden die ostdeutschen Werkzeugmaschinenbau-Betriebe, die bereits privatisiert sind, in einem radikalen Schnitt auf das in den westlichen Muttergesellschaften übliche Organisationsprinzip umgestellt. Bei den Treuhandfirmen ist der Umstrukturierungsprozeß nicht abgeschlossen. Hinsichtlich ihrer technischen Ausstattung wurden Werkzeugmaschinenbau-Betriebe zu Zeiten der DDR gege nüber anderen Industriezweigen bevorzugt. Unter den geänderten Rahmenbedingungen können sich diese "modernen" Produktionsanlagen als Scheinvorteil erweisen. Da die von DDR-Betrieben hergestellten Werkzeugmaschinen hauptsächlich auf die Ansprüche des sowjetischen Marktes ausgerichtet waren, wird mit neuen Marktanforderungen auch der Nutzwert der installierten Maschinen und Anlagen abnehmen. Insgesamt zeigt sich, daß das Jahr 1992 als "Schicksalsjahr" zu bezeichnen ist. Diejenigen Betriebe, die sich während dieses Jahres auf dem westlichen Werkzeugmaschinen-Markt nicht etablieren können, haben wenig Chancen, als Werkzeugmaschinen-Produzent zu überleben.

Die kleinen und mittleren Industrieunternehmen reprasentieren in Westdeutschland ein wichtiges Innovationspotential und machen dort einen Grosteil der Flexibilitat der Industrie aus. Fur Ostdeutschland erhoffte man sich von der Entflechtung der fruheren Kombinate, das eine Vielzahl mittelstandischer Unternehmen im Verarbeitenden Gewerbe entsteht. Dieser neu entstandene Mittelstand soll bezuglich Beschaftigung, Innovationspotential und Flexibilitat in den ostdeutschen Landern eine vergleichbare Bedeutung wie in Westdeutschland haben. Die Treuhandanstalt halt zur Unterstutzung der Privatisierung mittelstandischer Industrieunternehmen u.a. zwei Instrumente bereit: Durch Management-buy-outs (MBO) sollen ehemalige ostdeutsche Manager ihren fruheren Betrieb durch die Ubernahme in die Selbstandigkeit fuhren. Beim Management-buy-in (MBI) wird erfahrenen Managern aus Westdeutschland oder dem Ausland ermoglicht, sich mit einem bestehenden ostdeutschen Betrieb selbstandig zu machen.