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The double role of the endoplasmic reticulum chaperone tapasin in peptide optimization of HLA class I molecules

C M Cabrera1

  • 1Stem Cell Bank of Andalucia (Spanish Central Node), Hospital Universitario Virgen de las Nieves, Granada, Spain. carmenm.cabrera.sspa@juntadeandalucia.es

Scandinavian Journal of Immunology
|May 26, 2007
PubMed

During the assembly of the HLA class I molecules with peptides in the peptide-loading complex, a series of transient interactions are made with ER-resident chaperones. These interactions culminate in the trafficking of the HLA class I molecules to the cell surface and presentation of peptides to CD8(+) T lymphocytes. Within the peptide-loading complex, the glycoprotein tapasin exhibits a relevant function. This immunoglobulin (Ig) superfamily member in the endoplasmic reticulum membrane tethers empty HLA class I molecules to the transporter associated with antigen-processing (TAP) proteins. This review will address the current concepts regarding the double role that tapasin plays in the peptide optimization and surface expression of the HLA class I molecules.

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