Related Experiment Video
Updated: Aug 8, 2026
Preparation of CD4+ T Cells for Analysis of GD3 and GD2 Ganglioside Membrane Expression by Microscopy
Published on: November 8, 2016
Cytoplasmic tail-dependent localization of CD1b antigen-presenting molecules to MIICs
M Sugita1, R M Jackman, E van Donselaar
1Lymphocyte Biology Section, Division of Rheumatology and Immunology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Insights
CD1b proteins, crucial for T cell immunity, traffic to specialized endosomes for antigen presentation. This localization relies on CD1b
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- CD1 proteins function as antigen-presenting molecules in T cell-mediated immunity.
- The intracellular localization and trafficking pathways of CD1 proteins are not well understood.
- CD1b specifically presents microbial lipid antigens derived from external sources.
Purpose of the Study:
- To investigate the intracellular localization and trafficking of CD1b.
- To determine the mechanisms governing CD1b's movement to endocytic compartments.
- To compare CD1b trafficking with that of Major Histocompatibility Complex (MHC) class II molecules.
Main Methods:
- Immunofluorescence microscopy to visualize CD1b localization.
- Analysis of endocytic compartments and their relationship with CD1b.
- Mutational analysis of the CD1b cytoplasmic tail to identify trafficking motifs.
Main Results:
- CD1b was found to localize within endocytic compartments.
- These compartments are specialized endosomes, similar to those involved in MHC class II antigen loading.
- CD1b's localization to these compartments is dependent on a tyrosine-based motif within its cytoplasmic tail, independent of invariant chain association.
Conclusions:
- CD1b utilizes a distinct, self-reliant mechanism for trafficking to antigen-loading endosomes.
- This finding provides insights into the distinct pathways of antigen presentation by CD1 and MHC class II molecules.
- The identified tyrosine-based motif is critical for CD1b's functional localization in immune responses.
Abstract:
CD1 proteins have been implicated as antigen-presenting molecules for T cell-mediated immune responses, but their intracellular localization and trafficking remain uncharacterized. CD1b, a member of this family that presents microbial lipid antigens of exogenous origin, was found to localize to endocytic compartments that included the same specialized subset of endosomes in which major histocompatibility complex (MHC) class II molecules are proposed to bind endocytosed antigens. Unlike MHC class II molecules, which traffic to antigen-loading endosomal compartments [MHC class II compartments (MIICs)] primarily as a consequence of their association with the invariant chain, localization of CD1b to these compartments was dependent on a tyrosine-based motif in its own cytoplasmic tail.
More Related Videos
08:37In Situ MHC-tetramer Staining and Quantitative Analysis to Determine the Location, Abundance, and Phenotype of Antigen-specific CD8 T Cells in Tissues
Published on: September 22, 2017
12:09Use of Single Chain MHC Technology to Investigate Co-agonism in Human CD8+ T Cell Activation
Published on: February 28, 2019
Related Concept Videos
01:31Immunoglobulin-like Cell Adhesion Molecules
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
01:22T Cell Activation and Clonal Selection
Naive T cells that have not yet encountered an antigen express two primary CD...