MHC class II dimer of dimers

Mutations in MHC class II dimer of dimers contact residues: effects on antigen presentation.

The recent solutions of the MHC class II crystal structure reveal dimerization of the alphabeta heterodimers. These dimer of dimers structures may also exist either on resting cells or after engagement by TCR, and may be involved in B cell signaling and up-regulation of co-stimulatory molecules such as B7 which facilitate T cell activation. By combining crystallographic data on HLA-DR1 with the...

Amino acid substitutions in the putative MHC class II "dimer of dimers" interface inhibit CD4+ T cell activation.

Activation of T lymphocytes is dependent on multiple ligand-receptor interactions. The possibility that TCR dimerization contributes to T cell triggering was raised by the crystallographic analysis of MHC class II molecules. The MHC class II molecules associated as double dimers, and in such a way that two TCR (and two CD4 molecules) could bind simultaneously. Several subsequent studies have le...

MHC class II tetramers.

MHC class II tetramers have emerged as an important tool for characterization of the specificity and phenotype of CD4 T cell immune responses, useful in a large variety of disease and vaccine studies. Issues of specific T cell frequency, biodistribution, and avidity, coupled with the large genetic diversity of potential class II restriction elements, require targeted experimental design. Transl...

Regulation of MHC Class II

HLA-DM induces clip dissociation from MHC class II αβ dimers and facilitates peptide loading

Human leukocyte antigen DM (HLA-DM) molecules are structurally related to classical MHC class II molecules and reside in the lysosomallke compartment where class II-restricted antigen processing Is thought to occur. Yutsnt cell lines tacking HLA-DM ere defective In antigen processing and accumulate cuss II molecules associated wlth a nested set of invariant chain-derived peptkfes (clsas II-ssso...