β 2‐microglobulin with an endoplasmic reticulum retention signal increases the surface expression of folded class I major histocompatibility complex molecules

Joyce C. Solheim, Nancy A. Johnson, Beatriz M. Carreno, Wen‐Rong ‐R Lie, Ted H. Hansen

Research output: Contribution to journalArticle

12 Scopus citations

Abstract

With β2‐microglobulin2m) cell lines such as R1E/Db, the surface expression of class I major histocompatibility complex molecules is greatly impaired, and class I molecules that are on the surface are generally misfolded. To determine whether β2m must be continually present with the class I heavy chain for the class I molecule to reach the surface in a folded conformation, a sequence encoding an endoplasmic reticulum (ER) retention signal (KDEL) was attached onto the 3′ end of a β2m cDNA. After this chimeric cDNA was transfected into R1E/Db cells, β2m‐KDEL protein was detectable by an anti‐β2m serum within the cells but not at the cell surface. Interestingly, R1E/Db cells transfected with β2m‐KDEL were found to express a high level of conformationally correct Db molecules at the cell surface. This observation implies that β2m has a critical and temporal role in the de novo folding of the class I heavy chain. We propose that the critical time for β2m association is when the class I molecule is docked with the transporter associated with antigen processing (TAP) and first interacts with peptide.

Original languageEnglish (US)
Pages (from-to)3011-3016
Number of pages6
JournalEuropean Journal of Immunology
Volume25
Issue number11
DOIs
StatePublished - Nov 1995

    Fingerprint

Keywords

  • Conformation
  • Endoplasmic reticulum
  • Majro histocompatibility complex class I
  • R1E/D
  • β ‐microglobulin

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Cite this