Monoclonal antibodies (mAbs) specific for cell surface antigens are an invaluable tool to study immune receptor expression and function. Here, we outline a generalized reporter cell-based approach to the generation and high-throughput screening of mAbs specific for cell surface a ...
Fc receptor signaling plays a fundamental role in immune responses. A plethora of Fc �receptors (e.g., Fc gamma, Fc-alpha, and Fc-epsilon) are expressed on different immune cells, including natural killer cells, macrophages, mast cells, and neutrophils. Receptor clustering and activat ...
Phagocytosis is an immune receptor-mediated process whereby cells engulf large particles. The process is dynamic and requires several localized factors acting in concert with and sequentially after the engagement of immune receptors to envelope the particle. Once the particle is i ...
The covalent attachment of ubiquitin to a protein is one of the most common post-translational modifications and regulates diverse eukaryotic cellular processes. Ubiquitination of MHC class I was first described in the context of viral proteins which target MHC class I for degradation in ...
Major histocompatibility complex (MHC) class I molecules function to present pathogen-derived peptides to cytotoxic T cells or act as ligands for Natural Killer cells, thus alerting the immune system to the presence of invading pathogens. Furthermore MHC class I molecules can be strong ...
In the endoplasmic reticulum (ER), MHC class I molecules associate with several specialized proteins, forming a large macromolecular complex referred to as the “peptide-loading complex” (PLC). In the PLC, antigenic peptides undergo a stringent selection process for binding onto MHC c ...
The stability of the MHC (major histocompatibility complex) class I peptide repertoire is optimized during assembly in the endoplasmic reticulum (ER) and depends on the collective function of components of the peptide-loading complex (PLC). The chaperone-like molecule tapasin is t ...
MHC class I molecules display peptides at the cell surface that are mostly derived from cytosolic or nuclear proteins. Since peptide loading of MHC class I molecules occurs in the ER lumen, cytosolic peptides have to pass the ER membrane. The peptide transporter TAP translocates peptides over t ...
MHC class I molecules present peptides that are derived from intracellular proteins degraded by proteasomes. These peptides often require additional trimming by peptidases to fit into the peptide-binding grove of MHC class I. However, most peptides are rapidly recycled by the large het ...
The presentation of lipid antigens to T cells is mediated by the CD1 proteins. Purified functional CD1/lipid complexes are valuable tools to investigate such immune processes. Here, we describe how these complexes can be prepared in vitro, how they can be purified by chromatofocusing and how to ...
Natural Killer T (NKT) cells are a subset of T lymphocytes that recognize a wide variety of lipid antigens presented by CD1 molecules. NKT cells exhibit rapid activation after recognition of cognate antigens, secrete abundant amounts of T helper (Th) 1, Th2, and Th17 cytokines within hours of activ ...
Tetramer staining of CD4+ T cells is a valuable technique in immunology for detecting rare autoreactive T cells. Generating clones or cell lines from autoantigen tetramer-positive CD4+ T cells allows further characterization and phenotyping of autoreactive cells.
The major histocompatibility complex (MHC) class I restricted pathway of antigen processing allows the presentation of intracellular antigens to cytotoxic T lymphocytes. The proteasome is the main protease in the cytoplasm and the nucleus, which is responsible for the generation of ...
The ability of B lymphocytes to capture external antigens (Ag) and present them as peptide fragments, loaded on Major Histocompatibility complex (MHC) class II molecules, to CD4+ T cells is a crucial part of the adaptive immune response. This allows T-B cooperation, a cellular communication th ...
Ubiquitinated protein detection is often troublesome since in most cases this modification reduces the half-life of targeted proteins, inducing their degradation. Furthermore, ubiquitination is reversible thanks to the action of highly specific deubiquitinases present in ...
Proteases generate peptides that bind to MHC class II molecules to interact with a wide diversity of CD4+ T cells. They are expressed in dedicated organelles: endosomes and lysosomes of professional antigen presenting cells (pAPCs) such as B cells, macrophages, and dendritic cells. The iden ...
Professional antigen presenting cells, such as dendritic cells, are effective in activating T lymphocytes due to their unique ability to present antigens in the context of both MHC class I and II molecules. After successful loading with antigenic peptides MHC class II molecules traffic fr ...
Macroautophagy has recently emerged as an important catabolic process involved not only in innate immunity but also in adaptive immunity. Initially described to deliver intracellular antigens to MHC class II loading compartments, its molecular machinery has now also been describ ...
Rejection is still the major cause of allograft loss following organ transplantation and a more complete comprehension of the alloimmune response is required in order to develop new therapeutic approaches. Allogenicity is primarily generated by the expression of major histocomp ...
HLA-DM is now known to have a major contribution to the selection of immunodominant epitopes. A better understanding of the mechanisms controlling epitope selection can be achieved by examination of the biophysical behavior of major histocompatibility complex (MHC) class II molecu ...