@article{LodhaErhardDoelkenetal.2022, author = {Lodha, Manivel and Erhard, Florian and D{\"o}lken, Lars and Prusty, Bhupesh K.}, title = {The hidden enemy within: non-canonical peptides in virus-induced autoimmunity}, series = {Frontiers in Microbiology}, volume = {13}, journal = {Frontiers in Microbiology}, issn = {1664-302X}, doi = {10.3389/fmicb.2022.840911}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-263053}, year = {2022}, abstract = {Viruses play a key role in explaining the pathogenesis of various autoimmune disorders, whose underlying principle is defined by the activation of autoreactive T-cells. In many cases, T-cells escape self-tolerance due to the failure in encountering certain MHC-I self-peptide complexes at substantial levels, whose peptides remain invisible from the immune system. Over the years, contribution of unstable defective ribosomal products (DRiPs) in immunosurveillance has gained prominence. A class of unstable products emerge from non-canonical translation and processing of unannotated mammalian and viral ORFs and their peptides are cryptic in nature. Indeed, high throughput sequencing and proteomics have revealed that a substantial portion of our genomes comprise of non-canonical ORFs, whose generation is significantly modulated during disease. Many of these ORFs comprise short ORFs (sORFs) and upstream ORFs (uORFs) that resemble DRiPs and may hence be preferentially presented. Here, we discuss how such products, normally "hidden" from the immune system, become abundant in viral infections activating autoimmune T-cells, by discussing their emerging role in infection and disease. Finally, we provide a perspective on how these mechanisms can explain several autoimmune disorders in the wake of the COVID-19 pandemic.}, language = {en} } @article{vonLukowiczSchlegelHaerteletal.2021, author = {von Lukowicz, Hannah and Schlegel, Paul-Gerhardt and H{\"a}rtel, Christoph and Morbach, Henner and Haubitz, Imme and Wiegering, Verena}, title = {ESPED survey on newly diagnosed immune thrombocytopenia in childhood: how much treatment do we give?}, series = {Molecular and Cellular Pediatrics}, volume = {8}, journal = {Molecular and Cellular Pediatrics}, doi = {10.1186/s40348-021-00121-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261832}, year = {2021}, abstract = {Background Immune thrombocytopenia (ITP) is an autoimmune disease associated with isolated thrombocytopenia, which is caused by an imbalance between platelet production and platelet destruction. Petechial and mucous membrane hemorrhages are characteristic of ITP, but life-threatening bleeding rarely occurs. Depending on the bleeding symptoms, ITP can be treated with glucocorticoids (GC), intravenous immunoglobulins (IVIG), or in severe cases, platelet transfusions. Mild bleeding does not necessarily require therapy. Using the German Surveillance Unit for rare Pediatric Diseases (ESPED) we conducted a prospective survey on ITP patients in all German Children's Hospitals between September 2018 and August 2019. We collected data on ITP, including the clinical course, therapy implementation recommendations (according to the Association of German Scientific Medical Societies guidelines), outcome, and influence of treatment regimens depending on the treating physician´s experience with ITP patients. Results Of the 287 recorded cases of children with ITP, 268 questionnaires were sent to the authors. Two hundred seventeen of the questionnaires fulfilled the inclusion criteria. ITP affected boys and girls similarly, and the median age of manifestation was 3.5 years. The main reasons for hospitalization were thrombocytopenia, bleeding signs, hematomas, and/or petechiae. Bleeding scores were ≤ 3 in 96\% of children, which corresponded to a low-to-moderately low risk of bleeding. No life-threatening bleeding was documented. The most common therapies were IVIG (n = 59), GC (n = 33), or a combination of these (n = 17). Blood products (i.e., red blood cells, platelet concentrate, and fresh frozen plasma) were given to 13 patients. Compared to the established guidelines, 67 patients were over-treated, and 2 patients were under-treated. Conclusions Adherence to German ITP treatment guidelines is currently limited. To improve patient safety and medical care, better medical training and dissemination of the guidelines are required in line with targeted analyses of patients with serious bleeding events to identify potential risk constellations.}, language = {en} } @article{HanitschBaumannBoztugetal.2020, author = {Hanitsch, Leif and Baumann, Ulrich and Boztug, Kaan and Burkhard-Meier, Ulrike and Fasshauer, Maria and Habermehl, Pirmin and Hauck, Fabian and Klock, Gerd and Liese, Johannes and Meyer, Oliver and M{\"u}ller, Rainer and Pachlopnik-Schmid, Jana and Pfeiffer-Kascha, Dorothea and Warnatz, Klaus and Wehr, Claudia and Wittke, Kirsten and Niehues, Tim and von Bernuth, Horst}, title = {Treatment and management of primary antibody deficiency: German interdisciplinary evidence-based consensus guideline}, series = {European Journal of Immunology}, volume = {50}, journal = {European Journal of Immunology}, number = {10}, doi = {10.1002/eji.202048713}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225731}, pages = {1432 -- 1446}, year = {2020}, abstract = {This evidence-based clinical guideline provides consensus-recommendations for the treatment and care of patients with primary antibody deficiencies (PADs). The guideline group comprised 20 clinical and scientific expert associations of the German, Swiss, and Austrian healthcare system and representatives of patients. Recommendations were based on results of a systematic literature search, data extraction, and evaluation of methodology and study quality in combination with the clinical expertise of the respective representatives. Consensus-based recommendations were determined via nominal group technique. PADs are the largest clinically relevant group of primary immunodeficiencies. Most patients with PADs present with increased susceptibility to infections, however immune dysregulation, autoimmunity, and cancer affect a significant number of patients and may precede infections. This guideline therefore covers interdisciplinary clinical and therapeutic aspects of infectious (e.g., antibiotic prophylaxis, management of bronchiectasis) and non-infectious manifestations (e.g., management of granulomatous disease, immune cytopenia). PADs are grouped into disease entities with definitive, probable, possible, or unlikely benefit of IgG-replacement therapy. Summary and consensus-recommendations are provided for treatment indication, dosing, routes of administration, and adverse events of IgG-replacement therapy. Special aspects of concomitant impaired T-cell function are highlighted as well as clinical data on selected monogenetic inborn errors of immunity formerly classified into PADs (APDS, CTLA-4-, and LRBA-deficiency).}, language = {en} } @article{FroehlichSchwaneckGernertetal.2020, author = {Froehlich, Matthias and Schwaneck, Eva C. and Gernert, Michael and Gadeholt, Ottar and Strunz, Patrick-Pascal and Morbach, Henner and Tony, Hans-Peter and Schmalzing, Marc}, title = {Autologous Stem Cell Transplantation in Common Variable Immunodeficiency: A Case of Successful Treatment of Severe Refractory Autoimmune Encephalitis}, series = {Frontiers in Immunology}, volume = {11}, journal = {Frontiers in Immunology}, number = {1317}, issn = {1664-3224}, doi = {10.3389/fimmu.2020.01317}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-206972}, year = {2020}, abstract = {Common variable immunodeficiency (CVID) is the most common primary immunodeficiency in adults. It is associated with hypogammaglobulinemia, recurring infections and autoimmune phenomena. Treatment includes immunoglobulin substitution and immunosuppressants. Autoimmune neurological manifestations of CVID are rare and occur predominantly as granulomatous disease. We report the case of a 35-year-old woman with CVID who developed autoimmune encephalitis as demonstrated by double cerebral biopsy. Infectious or malignant causes could be excluded. Despite intensive immunosuppressive therapy with common regimens no significant improvement could be achieved. Ultimately, an autologous hematopoietic stem cell transplantation (HSCT) was performed, resulting in lasting complete remission of the encephalitis. To our knowledge, this is the first report of refractory autoimmune phenomena in CVID treated by autologous HSCT.}, language = {en} } @article{LangenhorstTabaresGuldeetal.2018, author = {Langenhorst, Daniela and Tabares, Paula and Gulde, Tobias and Becklund, Bryan R. and Berr, Susanne and Surh, Charles D. and Beyersdorf, Niklas and H{\"u}nig, Thomas}, title = {Self-recognition sensitizes mouse and human regulatory T cells to low-dose CD28 superagonist stimulation}, series = {Frontiers in Immunology}, volume = {8}, journal = {Frontiers in Immunology}, number = {1985}, doi = {10.3389/fimmu.2017.01985}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159387}, year = {2018}, abstract = {In rodents, low doses of CD28-specific superagonistic monoclonal antibodies (CD28 superagonists, CD28SA) selectively activate regulatory T cells (Treg). This observation has recently been extended to humans, suggesting an option for the treatment of autoimmune and inflammatory diseases. However, a mechanistic explanation for this phenomenon is still lacking. Given that CD28SA amplify T cell receptor (TCR) signals, we tested the hypothesis that the weak tonic TCR signals received by conventional CD4\(^{+}\) T cells (Tconv) in the absence of cognate antigen require more CD28 signaling input for full activation than the stronger TCR signals received by self-reactive Treg. We report that in vitro, the response of mouse Treg and Tconv to CD28SA strongly depends on MHC class II expression by antigen-presenting cells. To separate the effect of tonic TCR signals from self-peptide recognition, we compared the response of wild-type Treg and Tconv to low and high CD28SA doses upon transfer into wild-type or H-2M knockout mice, which lack a self-peptide repertoire. We found that the superior response of Treg to low CD28SA doses was lost in the absence of self-peptide presentation. We also tested if potentially pathogenic autoreactive Tconv would benefit from self-recognition-induced sensitivity to CD28SA stimulation by transferring TCR transgenic OVA-specific Tconv into OVA-expressing mice and found that low-dose CD28SA application inhibited, rather than supported, their expansion, presumably due to the massive concomitant activation of Treg. Finally, we report that also in the in vitro response of human peripheral blood mononuclear cells to CD28SA, HLA II blockade interferes with the expansion of Treg by low-dose CD28SA stimulation. These results provide a rational basis for the further development of low-dose CD28SA therapy for the improvement of Treg activity.}, language = {en} } @article{MurakawaHinzMothesetal.2015, author = {Murakawa, Yasuhiro and Hinz, Michael and Mothes, Janina and Schuetz, Anja and Uhl, Michael and Wyler, Emanuel and Yasuda, Tomoharu and Mastrobuoni, Guido and Friedel, Caroline C. and D{\"o}lken, Lars and Kempa, Stefan and Schmidt-Supprian, Marc and Bl{\"u}thgen, Nils and Backofen, Rolf and Heinemann, Udo and Wolf, Jana and Scheidereit, Claus and Landthaler, Markus}, title = {RC3H1 post-transcriptionally regulates A20 mRNA and modulates the activity of the IKK/NF-\(\kappa\)B pathway}, series = {Nature Communications}, volume = {6}, journal = {Nature Communications}, number = {7367}, doi = {10.1038/ncomms8367}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151596}, year = {2015}, abstract = {The RNA-binding protein RC3H1 (also known as ROQUIN) promotes TNF\(\alpha\) mRNA decay via a 3'UTR constitutive decay element (CDE). Here we applied PAR-CLIP to human RC3H1 to identify ~3,800 mRNA targets with >16,000 binding sites. A large number of sites are distinct from the consensus CDE and revealed a structure-sequence motif with U-rich sequences embedded in hairpins. RC3H1 binds preferentially short-lived and DNA damage-induced mRNAs, indicating a role of this RNA-binding protein in the post-transcriptional regulation of the DNA damage response. Intriguingly, RC3H1 affects expression of the NF-\(\kappa\)B pathway regulators such as I\(\kappa\)B\(\alpha\) and A20. RC3H1 uses ROQ and Zn-finger domains to contact a binding site in the A20 3'UTR, demonstrating a not yet recognized mode of RC3H1 binding. Knockdown of RC3H1 resulted in increased A20 protein expression, thereby interfering with I\(\kappa\)B kinase and NF-\(\kappa\)B activities, demonstrating that RC3H1 can modulate the activity of the IKK/NF-\(\kappa\)B pathway.}, language = {en} } @article{GirschickWolfMorbachetal.2015, author = {Girschick, Hermann and Wolf, Christine and Morbach, Henner and Hertzberg, Christoph and Lee-Kirsch, Min Ae}, title = {Severe immune dysregulation with neurological impairment and minor bone changes in a child with spondyloenchondrodysplasia due to two novel mutations in the ACP5 gene}, series = {Pediatric Rheumatology}, volume = {13}, journal = {Pediatric Rheumatology}, number = {37}, doi = {10.1186/s12969-015-0035-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149990}, year = {2015}, abstract = {Spondyloenchondrodysplasia (SPENCD) is a rare skeletal dysplasia, characterized by metaphyseal lesions, neurological impairment and immune dysregulation associated with lupus-like features. SPENCD is caused by biallelic mutations in the ACP5 gene encoding tartrate-resistant phosphatase. We report on a child, who presented with spasticity, multisystem inflammation, autoimmunity and immunodeficiency with minimal metaphyseal changes due to compound heterozygosity for two novel ACP5 mutations. These findings extend the phenotypic spectrum of SPENCD and indicate that ACP5 mutations can cause severe immune dysregulation and neurological impairment even in the absence of metaphyseal dysplasia.}, language = {en} } @article{RovitusoSchefflerWunschetal.2016, author = {Rovituso, Damiano M. and Scheffler, Laura and Wunsch, Marie and Kleinschnitz, Christoph and D{\"o}rck, Sebastian and Ulzheimer, Jochen and Bayas, Antonios and Steinman, Lawrence and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie}, title = {CEACAM1 mediates B cell aggregation in central nervous system autoimmunity}, series = {Scientific Reports}, volume = {6}, journal = {Scientific Reports}, doi = {10.1038/srep29847}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147690}, pages = {29847}, year = {2016}, abstract = {B cell aggregates in the central nervous system (CNS) have been associated with rapid disease progression in patients with multiple sclerosis (MS). Here we demonstrate a key role of carcinoembryogenic antigen-related cell adhesion molecule1 (CEACAM1) in B cell aggregate formation in MS patients and a B cell-dependent mouse model of MS. CEACAM1 expression was increased on peripheral blood B cells and CEACAM1\(^+\) B cells were present in brain infiltrates of MS patients. Administration of the anti-CEACAM1 antibody T84.1 was efficient in blocking aggregation of B cells derived from MS patients. Along these lines, application of the monoclonal anti-CEACAM1 antibody mCC1 was able to inhibit CNS B cell aggregate formation and significantly attenuated established MS-like disease in mice in the absence of any adverse effects. CEACAM1 was co-expressed with the regulator molecule T cell immunoglobulin and mucin domain -3 (TIM-3) on B cells, a novel molecule that has recently been described to induce anergy in T cells. Interestingly, elevated coexpression on B cells coincided with an autoreactive T helper cell phenotype in MS patients. Overall, these data identify CEACAM1 as a clinically highly interesting target in MS pathogenesis and open new therapeutic avenues for the treatment of the disease.}, language = {en} } @article{KoutsilieriLutzScheller2013, author = {Koutsilieri, E. and Lutz, M. B. and Scheller, C.}, title = {Autoimmunity, dendritic cells and relevance for Parkinson's disease}, series = {Journal of Neural Transmission}, volume = {120}, journal = {Journal of Neural Transmission}, doi = {10.1007/s00702-012-0842-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132308}, pages = {75-81}, year = {2013}, abstract = {Innate and adaptive immune responses in neurodegenerative diseases have become recently a focus of research and discussions. Parkinson's disease (PD) is a neurodegenerative disorder without known etiopathogenesis. The past decade has generated evidence for an involvement of the immune system in PD pathogenesis. Both inflammatory and autoimmune mechanisms have been recognized and studies have emphasized the role of activated microglia and T-cell infiltration. In this short review, we focus on dendritic cells, on their role in initiation of autoimmune responses, we discuss aspects of neuroinflammation and autoimmunity in PD, and we report new evidence for the involvement of neuromelanin in these processes.}, language = {en} }