Reagents and instruments for immunology, cell biology and molecular biology.

Human tetramers - Class II - BV421

MHC tetramers are complexes of four MHC molecules, associated with a specific peptide and bound to a fluorochrome. Class II tetramers bind to a distinct population of CD4+ T cells.

MHC class II tetramer staining is more technically challenging than class I tetramer staining.

Antigen-specific CD4+ T cells are more rare than antigen-specific CD8+ T cells
Affinity between the T cell receptor and MHC/peptide complex is generally lower
Acquisition of 100,000-200,000 CD4+ T cells is typically required
Exclusion gating essential
T cell expansion and/or pre-enrichment may be required

MHC tetramers are labeled with fluorescent molecules including phycoerythrin (PE), allophycocyanin (APC), or Brilliant Violet 421 (BV421) and thus allow detection of antigen-specific T cells by flow cytometry or fluorescence microscopy.