Publications by authors named "Birgit Hoeger"

T lymphocyte activation is a crucial process in the regulation of innate and adaptive immune responses. The ion channel-kinase TRPM7 has previously been implicated in cellular Mg homeostasis, proliferation, and immune cell modulation. Here, we show that pharmacological and genetic silencing of TRPM7 leads to diminished human CD4 T-cell activation and proliferation following TCR mediated stimulation.

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Cyclooxygenase-2 (COX-2) is a key regulator of inflammation. High constitutive expression enhances survival and proliferation of cancer cells, and adversely impacts antitumor immunity. The expression of is modulated by various signaling pathways.

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Localized intracellular calcium fluxes are indispensable for immunologically directed Fc receptor-mediated cellular phagocytosis. A similar dependency on calcium signals has been speculated to occur in efferocytosis, the clearance of non-opsonized apoptotic cell bodies by macrophages. In a recent study published in Nature Communications, Schappe et al.

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Helios, encoded by IKZF2, is a member of the Ikaros family of transcription factors with pivotal roles in T-follicular helper, NK- and T-regulatory cell physiology. Somatic IKZF2 mutations are frequently found in lymphoid malignancies. Although germline mutations in IKZF1 and IKZF3 encoding Ikaros and Aiolos have recently been identified in patients with phenotypically similar immunodeficiency syndromes, the effect of germline mutations in IKZF2 on human hematopoiesis and immunity remains enigmatic.

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Helios, a member of the Ikaros family of transcription factors, is predominantly expressed in developing thymocytes, activated T cells, and regulatory T cells (T). Studies in mice have emphasized its role in maintenance of T immunosuppressive functions by stabilizing Foxp3 expression and silencing the locus. However, its contribution to human immune homeostasis and the precise mechanisms by which Helios regulates other T cell subsets remain unresolved.

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The WAVE regulatory complex (WRC) is crucial for assembly of the peripheral branched actin network constituting one of the main drivers of eukaryotic cell migration. Here, we uncover an essential role of the hematopoietic-specific WRC component HEM1 for immune cell development. Germline-encoded HEM1 deficiency underlies an inborn error of immunity with systemic autoimmunity, at cellular level marked by WRC destabilization, reduced filamentous actin, and failure to assemble lamellipodia.

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Article Synopsis
  • Researchers found biallelic mutations in the DEF6 gene in patients with an immune disorder and systemic autoimmunity, shedding light on how immune responses can malfunction.
  • The study revealed that these mutations disrupt the regulation of the CTLA-4 protein's movement to the surface of T cells, which is crucial for controlling immune responses.
  • The findings suggest that targeting DEF6 could be a potential strategy for treating autoimmune diseases and cancer, as one patient responded well to CTLA-4-Ig treatment.
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In 2016, the United Nations declared the need for urgent action to combat the global threat of antimicrobial resistance (AMR). In support of this effort, the pharmaceutical industry has committed to measures aimed at improving the stewardship of antibiotics both within and outside the clinic. Notably, a group of companies collaborated to specifically address concerns related to antibiotic residues being discharged from manufacturing sites.

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Background: Although autoimmunity and hyperinflammation secondary to recombination activating gene (RAG) deficiency have been associated with delayed diagnosis and even death, our current understanding is limited primarily to small case series.

Objective: Understand the frequency, severity, and treatment responsiveness of autoimmunity and hyperinflammation in RAG deficiency.

Methods: In reviewing the literature and our own database, we identified 85 patients with RAG deficiency, reported between 2001 and 2016, and compiled the largest case series to date of 63 patients with prominent autoimmune and/or hyperinflammatory pathology.

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Phosphatase of regenerating liver (PRL)-3 () has gained much attention in cancer research due to its involvement in tumor promoting and metastatic processes. It belongs to the protein tyrosine phosphatase (PTP) superfamily and is thought to follow the catalytic mechanism shared by this family, which aside from the conserved active-site amino acids includes a conserved glutamic acid residue that is usually required for the integrity of the active site in PTPs. We noted that in structures of PRL-3, PRL-1, and PTEN these residues do not clearly align and therefore we sought to investigate if the glutamic acid residue fulfills its usual function in these proteins.

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Background: The actin-interacting protein WD repeat-containing protein 1 (WDR1) promotes cofilin-dependent actin filament turnover. Biallelic WDR1 mutations have been identified recently in an immunodeficiency/autoinflammatory syndrome with aberrant morphology and function of myeloid cells.

Objective: Given the pleiotropic expression of WDR1, here we investigated to what extent it might control the lymphoid arm of the immune system in human subjects.

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Specific granule deficiency (SGD) is a rare disorder characterized by abnormal neutrophils evidenced by reduced granules, absence of granule proteins, and atypical bilobed nuclei. Mutations in () are one molecular etiology of the disease. Although C/EBPε has been studied extensively, the impact of mutations on neutrophil biology remains elusive.

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Nuclear factor kappa-light-chain-enhancer of activated B cells 1 (NF-κB1)-related human primary immune deficiencies have initially been characterized as defining a subgroup of common variable immunodeficiencies (CVIDs), representing intrinsic B-cell disorders with antibody deficiency and recurrent infections of various kind. Recent evidence indicates that NF-κB1 haploinsufficiency underlies a variable type of combined immunodeficiency (CID) affecting both B and T lymphocyte compartments, with a broadened spectrum of disease manifestations, including Epstein-Barr virus (EBV)-induced lymphoproliferative disease and immediate life-threatening consequences. As part of this review series focused on EBV-related primary immunodeficiencies, we discuss the current clinical and molecular understanding of monoallelic germline mutations with special focus on the emerging context of EBV-associated disease.

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Protein tyrosine phosphatases (PTPs) are important enzymes in health and disease, and chemical tools are crucial to understand and modulate their biological roles. PTP1B is involved in diabetes, obesity and cancer. One of the main challenges for the design of chemical tools for PTP1B is the homology to TCPTP, making tool selectivity a highly challenging task.

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Computationally supported development of small molecule inhibitors has successfully been applied to protein tyrosine phosphatases in the past, revealing a number of cell-active compounds. Similar approaches have also been used to screen for small molecule inhibitors for the cancer-related phosphatases of regenerating liver (PRL) family. Still, selective and cell-active compounds are of limited availability.

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Protein tyrosine phosphatases (PTPs) play crucial roles in health and disease. Chemical modulators of their activity are vital tools to study their function. An important aspect is the accessibility of these tools, which is usually limited or not existent due to the required, often complex synthesis of the molecules.

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The Organisation for Economic Co-operation and Development (OECD) 308 water-sediment transformation test has been routinely conducted in Phase II Tier A testing of the environmental risk assessment (ERA) for all human pharmaceutical marketing authorization applications in Europe, since finalization of Environmental Medicines Agency (EMA) ERA guidance in June 2006. In addition to the "Ready Biodegradation" test, it is the only transformation test for the aquatic/sediment compartment that supports the classification of the drug substance for its potential persistence in the environment and characterizes the fate of the test material in a water-sediment environment. Presented is an overview of 31 OECD 308 studies conducted by 4 companies with a focus on how pharmaceuticals behave in these water-sediment systems.

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To identify molecular effects of the antineoplastic agent protein kinase C inhibitor 412 (PKC412) (midostaurin), we applied gene expression profiling in zebrafish using whole-genome microarrays. Behavioral, developmental, and physiological effects were investigated in order to analyze for correlations between altered gene expression profiles with effects on development and physiology. Zebrafish blastula-stage embryos were exposed for 6 days postfertilization to nominal levels of 2 and 40 μg/l PKC412.

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Through the concerted evaluations of thousands of commercial substances for the qualities of persistence, bioaccumulation, and toxicity as a result of the United Nations Environment Program's Stockholm Convention, it has become apparent that fewer empirical data are available on bioaccumulation than other endpoints and that bioaccumulation models were not designed to accommodate all chemical classes. Due to the number of chemicals that may require further assessment, in vivo testing is cost prohibitive and discouraged due to the large number of animals needed. Although in vitro systems are less developed and characterized for fish, multiple high-throughput in vitro assays have been used to explore the dietary uptake and elimination of pharmaceuticals and other xenobiotics by mammals.

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The detection of low levels of pharmaceuticals in aquatic environments has lately raised concerns regarding possible adverse effects of these highly active substances on aquatic organisms. The non-steroidal anti-inflammatory drug diclofenac (DCF) is one of the pharmaceutical substances regularly detected in surface waters and has lately been demonstrated to elicit adverse effects in salmonid species at environmentally relevant concentrations. The aim of the present study was to investigate the distribution of DCF in indigenous brown trout (Salmo trutta f.

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The detection of residues of various pharmaceuticals in surface waters during the last two decades has prompted concerns about possible adverse effects of this kind of pollution on aquatic organisms. The objective of the present study was to investigate effects of the non-steroidal anti-inflammatory drug diclofenac, one of the pharmaceuticals most prevalent in surface waters, on brown trout (Salmo trutta f. fario), a salmonid species native to German rivers.

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The objective of the present study was to investigate the influence of chronic exposure to municipal sewage treatment effluent at environmentally relevant concentrations on immune parameters in rainbow trout (Oncorhynchus mykiss), including the assessment of potential differences in reactivity between sexually mature male and female fish. Trout were exposed to 1.5 and 15% (v/v) secondary treated municipal sewage effluent for 32 weeks.

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