The Tetramer Core Laboratory provides MHC class II tetramer reagents for collaborators both within and outside BRI. These tetramers are synthetic protein conjugates that allow the direct detection of antigen specific T cells by flow cytometry.
Bill Kwok, PhD
What is a tetramer?
MHC “tetramers” are a multivalent synthetic mimic of the peptide binding proteins found on the surface of antigen presenting cells. Our tetramers are produced from soluble biotinylated Class II α a/b dimers conjugated around a fluorescent labeled streptavidin core. Class II tetramer reagents are a flow cytometry reagent that can be used to study human CD4+ T cell responses in a wide variety of disease settings. Because of the exquisite sensitivity and specificity of the MHC-peptide-TCR complex, tetramers can be used to individually label, enumerate, and sort T cells with one known antigen specificity.
Tetramers produced in our facility have been used to detect CD4+ (helper) T cells and have facilitated the study of viral immunity, autoimmune diseases, allergic responses and cancer. The class II MHC proteins are produced using stable insect cell cultures and purified by affinity chromatography. The purified proteins are loaded with exogenous peptide and conjugated using PE labeled streptavidin. In some cases we are able to provide T cell clones for use as experimental positive controls.