Major histocompatibility complex class I assembly within endolysosomal pathways

Dual role of the peptide-loading complex as proofreader and limiter of MHC-I presentation

“…Suboptimal loading with low-affinity peptides affects pMHC-I stability and leads to retention of MHC-I molecules in the secretory and recycling pathways. Thus, manipulation of pMHC-I biogenesis by deletion, downregulation, or mutation of PLC components leads to a reduction of MHC-I molecules on the cell surface—a process, utilized by many viruses and cancer cells to evade immune surveillance ( 2 , 21 – 27 ). However, the impact of individual PLC components on the quantity of MHC-I surface molecules, especially of different MHC-I allomorphs, and the effect on the presentation of defined pMHC-I complexes are not yet fully elucidated.…”