Gene transfer experiments imply instructive role of major histocompatibility complex class I molecules in cellular peptide processing.
DBA/2-derived mouse tumor cells were transfected with the H-2 Kb gene. Naturally processed minor histocompatibility (H) peptides were extracted from both transfected and non-transfected cells by acid elution, and were separated by high-performance liquid chromatography. Kb-restricted minor H epitopes corresponding to H-4b and mapki, both encoded by non-major histocompatibility complex genes of DBA/2, were readily detected by the respective cytotoxic T lymphocyte in peptides extracted from Kb-transfected, but not from non-transfected or Db-transfected cells. Titration experiments indicated at least 3000-fold less copies of correctly processed Kb-restricted epitopes in cells without Kb as compared to cells with Kb. Since we estimate the copy number of Kb-restricted H-4b epitopes in Kb-expressing transfectants to be less than 1000 per cell, the pool size of H-4b epitopes correctly processed in the absence of Kb should be less than 1/3 copy per cell.
Max-Planck-Institut für Biologie, Abteilung Immunogenetik, Tübingen, FRG.
H J
HJ
Wallny
O
O
Rötzschke
K
K
Falk
G
G
Hämmerling
H G
HG
Rammensee
D000818:Animals; D000939:Epitopes; D006183:H-2 Antigens / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008811:Mice, Inbred DBA; D010455:Peptides / Q000378:metabolism*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection
D000939:Epitopes; D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; D010455:Peptides