Interleukin-2 (IL-2) was one of the first cytokines discovered and its central role in T cell function soon led to the notion that the cytokine could specifically activate immune cells to combat cancer cells. Recombinant human IL-2 (recIL-2) belonged to the first anti-cancer immunotherapeutics that received marketing authorization and while it mediated anti-tumor effects in some cancer entities, treatment was associated with severe and systemic side effects. RecIL-2 holds an exceptional therapeutic potential, which can either lead to stimulation of the immune system - favorable during cancer treatment - or immunosuppression - used for treatment of inflammatory diseases such as autoimmunity.
View Article and Find Full Text PDFImmune-related adverse outcome pathways (irAOPs) are a toxicological tool for the structuring of complex immunological mechanisms. The EU-funded IMI-project imSAVAR analyses the applicability of irAOPs in pre-clinical safety assessment of immunotherapies. Here, we use immunotherapy with interleukin (IL)-2 as a use case to develop an irAOP for IL-2-mediated vascular leakage (VL).
View Article and Find Full Text PDFThis work focuses on the need for modeling and predicting adverse outcomes in immunotoxicology to improve nonclinical assessments of the safety of immunomodulatory therapies. The integrated approach includes, first, the adverse outcome pathway concept established in the toxicology field, and, second, the systems medicine disease map approach for describing molecular mechanisms involved in a particular pathology. The proposed systems immunotoxicology workflow is illustrated with chimeric antigen receptor (CAR) T cell treatment as a use case.
View Article and Find Full Text PDFType I interferons (IFN) are pro-inflammatory cytokines which can also exert anti-inflammatory effects via the regulation of interleukin (IL)-1 family members. Several studies showed that interferon receptor (IFNAR)-deficient mice develop severe liver damage upon treatment with artificial agonists such as acetaminophen or polyinosinic:polycytidylic acid. In order to investigate if these mechanisms also play a role in an acute viral infection, experiments with the family member Rift Valley fever virus (RVFV) were performed.
View Article and Find Full Text PDFThe most serious complication in the treatment of hemophilia A (HA) is the development of factor (F)VIII inhibitors or antidrug antibodies (ADA) occurring in 25-35% of patients with severe HA. The immunological mechanisms underlying the development of ADA against FVIII products have not been completely understood yet. Immunological danger signals associated with events such as infection or surgery have been suggested to play a critical role.
View Article and Find Full Text PDFHuman cytomegalovirus (HCMV) infection is associated with severe disease conditions either following congenital transmission of the virus or viral reactivation in immunosuppressed individuals. Consequently, the establishment of a protective vaccine is of high medical need. Several candidates have been tested in preclinical and clinical studies, yet no vaccine has been licensed.
View Article and Find Full Text PDFVaccine-associated enhanced respiratory disease (VAERD) is a severe complication for some respiratory infections. To investigate the potential for VAERD induction in coronavirus disease 2019 (COVID-19), we evaluate two vaccine leads utilizing a severe hamster infection model: a T helper type 1 (T1)-biased measles vaccine-derived candidate and a T2-biased alum-adjuvanted, non-stabilized spike protein. The measles virus (MeV)-derived vaccine protects the animals, but the protein lead induces VAERD, which can be alleviated by dexamethasone treatment.
View Article and Find Full Text PDFHuman immunoglobulin products are used for the treatment of a number of diseases, such as primary or secondary immunodeficiencies and autoimmune conditions due to the complete absence of antibodies or the production of defective immunoglobulins. Quality control of human immunoglobulin products is essential to ensure therapeutic functionality and safety. This includes testing for Fc function and anticomplementary activity (ACA), as well as verification of appropriate molecular size distribution using size-exclusion chromatography as prescribed in the European Pharmacopoeia (Ph.
View Article and Find Full Text PDFSince the approval of the first monoclonal antibody (mAb) in 1986, a huge effort has been made to guarantee safety and efficacy of therapeutic mAbs. As of July 2021, 118 mAbs are approved for the European market for a broad range of clinical indications. In order to ensure clinical efficacy and safety aspects, (pre-)clinical experimental approaches evaluate the respective modes of action (MoA).
View Article and Find Full Text PDFType I interferons (IFNs) are a first line of defence against viral infections. Upon infection, a first small wave of early type I IFN, mainly IFN-β and particularly IFN-α, are induced and bind to the type I IFN receptor (IFNAR) to amplify the IFN response. It was shown for several viruses that robust type I IFN responses require this positive feedback loop via the IFNAR.
View Article and Find Full Text PDFThe exact role of innate immune cells upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and their contribution to the formation of the corona virus-induced disease (COVID)-19 associated cytokine storm is not yet fully understood. We show that human differentiated myeloid dendritic cells (mDC) as well as M1 and M2 macrophages are susceptible to infection with SARS-CoV-2 but are not productively infected. Furthermore, infected mDC, M1-, and M2 macrophages show only slight changes in their activation status.
View Article and Find Full Text PDFIFN-γ is an enigmatic cytokine that shows direct anti-viral effects, confers upregulation of MHC-II and other components relevant for antigen presentation, and that adjusts the composition and balance of complex cytokine responses. It is produced during immune responses by innate as well as adaptive immune cells and can critically affect the course and outcome of infectious diseases, autoimmunity, and cancer. To selectively analyze the function of innate immune cell-derived IFN-γ, we generated conditional IFN-γOFF mice, in which endogenous IFN-γ expression is disrupted by a loxP flanked gene trap cassette inserted into the first intron of the IFN-γ gene.
View Article and Find Full Text PDFIntroduction: The most severe side effect in haemophilia A treatment is the development of antifactor VIII antibodies, also called inhibitors. Why inhibitors develop in a proportion of treated patients while others are unaffected still remains unanswered. The presence of immunological danger signals, associated with events such as infection or surgery, has been proposed to play a role.
View Article and Find Full Text PDFUpon treatment with polyinosinic:polycytidylic acid [poly(I:C)], an artificial double-stranded RNA, type I interferon receptor-deficient (IFNAR) mice develop severe liver injury seen by enhanced alanine aminotransferase (ALT) activity in the serum that is not observed in their wildtype (WT) counterparts. Recently, we showed that liver injury is mediated by an imbalanced expression of interleukin (IL)-1β and its receptor antagonist (IL1-RA) in the absence of type I IFN. Here we show that despite comparable expression levels of IL-1β in livers and spleens, spleens of poly(I:C)-treated IFNAR mice show no signs of injury.
View Article and Find Full Text PDFThe first-in-human clinical trial of the CD28-specific monoclonal antibody (mAb) TGN1412 resulted in a life-threatening cytokine release syndrome. Although TGN1412 was designed as IgG4, known for weak Fc:Fcγ receptor (FcγR) interactions, these interactions contributed to TGN1412-induced T-cell activation. Using cell lines (TFs) expressing human FcγRI, -IIa, -IIb, or -III, we show that TGN1412 and TGN1412 as IgG1 and IgG2 are bound by FcγRs as it can be deduced from literature.
View Article and Find Full Text PDFThe development of novel vaccination strategies is a persistent challenge to provide effective prophylactic treatments to encounter viral infections. In general, the physical conjugation of selected vaccine components, e.g.
View Article and Find Full Text PDFThe most severe side effect in haemophilia A (HA) treatment is the development of anti-factor VIII antibodies, also called inhibitors. Why inhibitors develop in a proportion of treated HA patients and how this can be prevented remains largely unanswered. Among numerous theories, the presence of immunological danger signals, associated with events such as surgery or infection, has been proposed to play a role.
View Article and Find Full Text PDFFunctional impairment of T-cells and a concomitant augmented expression of programmed death-1 (PD-1) have been observed in visceral leishmaniasis patients, as well as in experimental models for visceral and cutaneous leishmaniasis. The PD-1/PD-1-ligand (PD-1/PD-L) interaction negatively regulates T-cell effector functions, which are required for parasite control during leishmaniasis. The aim of this study was to elucidate the impact of the PD-1/PD-L axis in a human primary infection model of ().
View Article and Find Full Text PDFCytokine regulation of high-output nitric oxide (NO) derived from inducible NO synthase (iNOS) is critically involved in inflammation biology and host defense. Herein, we set out to characterize the role of type I interferon (IFN) as potential regulator of hepatic iNOS and . In this regard, we identified in murine Hepa1-6 hepatoma cells a potent synergism between pro-inflammatory interleukin-β/tumor necrosis factor-α and immunoregulatory IFNβ as detected by analysis of iNOS expression and nitrite release.
View Article and Find Full Text PDFUnlabelled: Type I interferons (IFNs) crucially contribute to host survival upon viral infections. Robust expression of type I IFNs (IFN-α/β) and induction of an antiviral state critically depend on amplification of the IFN signal via the type I IFN receptor (IFNAR). A small amount of type I IFN produced early upon virus infection binds the IFNAR and activates a self-enhancing positive feedback loop, resulting in induction of large, protective amounts of IFN-α.
View Article and Find Full Text PDFTherapeutic monoclonal antibodies (mAbs) such as the superagonistic, CD28-specific antibody TGN1412, or OKT3, an anti-CD3 mAb, can cause severe adverse events including cytokine release syndrome. A predictive model for mAb-mediated adverse effects, for which no previous knowledge on severe adverse events to be expected or on molecular mechanisms underlying is prerequisite, is not available yet. We used a humanized mouse model of human peripheral blood mononuclear cell-reconstituted NOD-RAG1-/-Aβ-/-HLADQ(tg+ or tg-)IL-2Rγc-/- mice to evaluate its predictive value for preclinical testing of mAbs.
View Article and Find Full Text PDFMurine cytomegalovirus (MCMV) proteins m142 and m143 are essential for viral replication. They bind double-stranded RNA and prevent protein kinase R-induced protein synthesis shutoff. Whether the two viral proteins have additional functions such as their homologs in human cytomegalovirus do remained unknown.
View Article and Find Full Text PDFUnlabelled: In 2012, the first cases of infection with the Middle East respiratory syndrome coronavirus (MERS-CoV) were identified. Since then, more than 1,000 cases of MERS-CoV infection have been confirmed; infection is typically associated with considerable morbidity and, in approximately 30% of cases, mortality. Currently, there is no protective vaccine available.
View Article and Find Full Text PDFUnlabelled: To induce and trigger innate and adaptive immune responses, antigen-presenting cells (APCs) take up and process antigens. Retroviral particles are capable of transferring not only genetic information but also foreign cargo proteins when they are genetically fused to viral structural proteins. Here, we demonstrate the capacity of lentiviral protein transfer vectors (PTVs) for targeted antigen transfer directly into APCs and thereby induction of cytotoxic T cell responses.
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