Chitin oligomers promote lymphoid innate and adaptive immune cell activation.

Chitin is a highly abundant N-acetylglucosamine polysaccharide that has been linked to immune responses in the context of fungal infections and allergic asthma, especially to T helper 2 immune responses. Unfortunately, due to the frequent use of crude chitin preparations of unknown purity and degree of polymerization, there is still great uncertainty about how chitin activates different parts of the human immune system. We recently identified chitin oligomers of 6 N-acetylglucosamine units as the smallest immunologically active chitin motif and the innate immune receptor TLR2 as a primary chitin sensor on human and murine myeloid cells, but the response of further immune cells (e.

Simultaneous Identification of Functional Antigen-Specific CD8 and CD4 Cells after In Vitro Expansion Using Elongated Peptides.

Elongated peptides (EPs), containing possibly one or multiple epitope/s, are increasingly used for the screening of antigen-specific CD8 and CD4 cell responses. Here, we present an in vitro protocol that allows the amplification of antigen-specific cells and the subsequent functional analysis of both T cell types using EPs. Known viral-derived epitopes were elongated to 20 mer EPs on the N-, C-, and both termini for HLA class I binders, or on the N- and C- termini for HLA class II binders.

A new synthetic toll-like receptor 1/2 ligand is an efficient adjuvant for peptide vaccination in a human volunteer.

Background: We previously showed that the bacterial lipopeptide PamCys-Ser-Ser, meanwhile established as a toll-like receptor (TLR) 1/2 ligand, acts as a strong adjuvant for the induction of virus specific CD8 T cells in mice, when covalently coupled to a synthetic peptide.

Case Presentation: We now designed a new water-soluble synthetic PamCys-derivative, named XS15 and characterized it in vitro by a TLR2 NF-κB luciferase reporter assay. Further, the capacity of XS15 to activate immune cells and stimulate peptide-specific CD8 T and NK cells by 6-sulfo LacNAc monocytes was assessed by flow cytometry as well as cytokine induction using immunoassays.

Actively personalized vaccination trial for newly diagnosed glioblastoma.

Patients with glioblastoma currently do not sufficiently benefit from recent breakthroughs in cancer treatment that use checkpoint inhibitors. For treatments using checkpoint inhibitors to be successful, a high mutational load and responses to neoepitopes are thought to be essential. There is limited intratumoural infiltration of immune cells in glioblastoma and these tumours contain only 30-50 non-synonymous mutations.

Activated integrins identify functional antigen-specific CD8 T cells within minutes after antigen stimulation.

Immediate β-integrin activation upon T cell receptor stimulation is critical for effective interaction between T cells and their targets and may therefore be used for the rapid identification and isolation of functional T cells. We present a simple and sensitive flow cytometry-based assay to assess antigen-specific T cells using fluorescent intercellular adhesion molecule (ICAM)-1 multimers that specifically bind to activated β-integrins. The method is compatible with surface and intracellular staining; it is applicable for monitoring of a broad range of virus-, tumor-, and vaccine-specific CD8 T cells, and for isolating viable antigen-reacting cells.

Expression of Desmoglein 2, Desmocollin 3 and Plakophilin 2 in Placenta and Bone Marrow-Derived Mesenchymal Stromal Cells.

Many controversial results exist when comparing mesenchymal stromal cells (MSCs) derived from different sources. Reasons include not only variables in tissue origin, but also methods of cell preparation or choice of expansion media which can strongly influence the expression and hence, function of the cells. In this short report we aimed to investigate the expression of the cell anchoring proteins desmoglein 2, desmocollin 3 and plakophilin 2 in early passage placenta-derived MSCs of fetal (fetal pMSCs) and maternal (maternal pMSCs) origins versus adult bone marrow-derived MSCs (bmMSCs) that were expanded and cultured under the same good manufacturing practice (GMP) conditions.

Validation of Immunomonitoring Methods for Application in Clinical Studies: The HLA-Peptide Multimer Staining Assay.

Background: Validated assays are essential to generate data with defined specificity, consistency, and reliability. Although the process of validation is required for applying immunoassays in the context of clinical studies, reports on systematic validation of in vitro T cell assays are scarce so far. We recently validated our HLA-peptide multimer staining assay in a systematic manner so as to qualify the method for monitoring antigen-specific T cell responses after immunotherapy.