The monocyte activation test (MAT) is used to detect pyrogens in pharmaceutical products and serves as replacement of the rabbit pyrogen test. The peripheral blood mononuclear cell-based MAT assay requires the addition of serum to the medium and is performed with either fetal bovine serum (FBS) or human serum (HS). Since the capacity to detect non-endotoxin pyrogens (NEPs) in a sensitive manner is an important strength of MAT compared to the bacterial endotoxin test, the performance of the MAT using FBS and HS was compared using endotoxin and several NEPs.
View Article and Find Full Text PDFActivation of antigen-presenting dendritic cells (DCs) and the complement system are essential early events in the immune defense against invading pathogens. Recently, we and others demonstrated immunological crosstalk between signaling from receptors recognizing complement activation products and PAMPs on DCs. This affects DC effector function, as demonstrated by the finding that C5a prevents induction of pro-inflammatory cytokines by toll-like receptor (TLR) ligands in human monocyte-derived DCs (moDCs).
View Article and Find Full Text PDFCrosstalk between complement component 5a receptors (C5aRs) and TLRs in dendritic cells (DCs) occurs upon pathogen invasion; however, studies on C5aR and TLR crosstalk mainly focused on the modulating effect of C5a on TLR-induced cytokine production. To elucidate the breadth of C5aR and TLR4 crosstalk, the effect of simultaneous treatment with C5a and LPS was investigated in human monocyte-derived DCs (moDCs) 2 h after stimulation using whole transcriptome sequencing analysis. Although the effect of C5a on hallmark genes defining TLR4-induced DC maturation was limited at this time point, RNA sequencing analysis revealed a great variety of novel C5a targets, of which many interfere with TLR4-mediated immune activation.
View Article and Find Full Text PDFTLR4 ligation can activate both the MyD88 and the Toll-IL-1 receptor domain-containing adaptor inducing IFN-β (TRIF) signaling route. Whereas MyD88 is generally recognized as a universal adaptor for pro-inflammatory responses, TRIF is mainly thought to contribute to specific type I IFN responses. Here, we investigated the contribution of both MyD88 and TRIF to TLR4-mediated pro-inflammatory dendritic cell (DC) differentiation in human.
View Article and Find Full Text PDFEx vivo generated monocyte-derived dendritic cells (DCs) are used as a cellular vaccine against cancer in clinical trials. In order to be able to induce an efficient tumour-specific CTL response during immunotherapy, DCs have to be able to migrate to the lymph node and produce the Th1 polarizing cytokine, IL-12p70, upon encounter of T cells in the lymph node. However, most clinically used DCs do not produce IL-12p70 upon T cell contact.
View Article and Find Full Text PDFThe growing number of clinical studies, using monocyte-derived DC therapy, requires protocols where a sufficient number of dendritic cell (DCs) are produced according to current Good Manufacturing Practice guidelines. Therefore, a closed culture system for the generation of DCs is inevitable. One cost-effective way to isolate monocytes directly from leukapheresis material in a closed system is by elutriation with the Elutra cell separation system.
View Article and Find Full Text PDFSerine proteinases from inflammatory cells, including polymorphonuclear neutrophils, are involved in various inflammatory disorders, like pulmonary emphysema and rheumatoid arthritis. Inhibitors of these serine proteinases are potential drug candidates for the treatment of these disorders, since they prevent the unrestricted proteolysis. This study describes a novel specific antistasin-type inhibitor of neutrophil serine proteinases, we called Fahsin.
View Article and Find Full Text PDFBackground: On SDS-PAGE grass pollen group-5 allergens migrate as a doublet with an apparent molecular mass (M(r)) of 25 kDa. Immunoblot analysis revealed additional group 5 reactivity at double and half this M(r). The aim of this study was to investigate these group 5 molecular entities and to compare their allergenicity and behavior in quantitative immunoassays.
View Article and Find Full Text PDFBackground: Production of soluble correctly folded recombinant group 1 allergens has proven to be difficult. Purified natural group 1 allergens could be an alternative for application in immunotherapy.
Objective: Cloning and expression of recombinant Dac g 1; purification of natural Dac g 1 variants and immunochemical characterization of these molecules.