Pockets and four compartments of MHC class II binding groove.

<p>(A) The MHC cleft is shown using cartoon representation. The backbone of MBP peptide is shown in cartoon and the C-alpha atoms in sphere representations. The residues forming the pockets are shown in Van der Waals representation. (B) Region D1 (in red), D2 (blue), D3 (green) and D4 (yellow).