MHC and MHC‑like molecules: Structural perspectives on the design of molecular vaccines

Abstract

Major histocompatibility complex (MHC) molecules bind and present short antigenic peptide fragments on the surface of antigen presenting cells (APCs) to T‑cell receptors. Recognition of peptide‑MHC complexes by T‑cells initiates a cascade of signals in T‑cells and activated cells either destroy or help to destroy the APC. The MHCs are divided into three subgroups: MHC class I, MHC class II and MHC class III. In addition, nonclassical MHC molecules and MHC‑like molecules play a pivotal role in shaping our understanding of the immune response. In the design of molecular vaccines for the treatment of diseases, an understanding of the three‑dimensional structure of MHC, its interaction with peptide ligands and its interaction with the T‑cell receptor are important prerequisites, all of which are discussed herein.