Induction of mRNA for HLA-DR beta in human keratinocytes cocultured with interferon-gamma.
Explanted human keratinocytes exposed in vitro to recombinant interferon-gamma (IFN-gamma) were investigated for the appearance of mRNA for HLA-DR. Using in situ hybridization with a (35S)UTP-labelled HLA-DR beta cRNA probe, mRNA-positive cells were detected already within 6 h with maximal numbers of positive cells as well as the amount of mRNA per cell after 48 h. The corresponding protein HLA-DR, as analysed by immunoperoxidase staining, was detected on 20%-40% of the cells after 24 h and on almost all cells within 48 h. The expression of HLA-DQ and -DP antigens were always exceeded by that of HLA-DR. Whereas an increase in the concentration of IFN-gamma above 50 U/ml did not affect the maximal level of HLA-DR reactive cells, there was a fourfold increase in the frequency of cells reactive with HLA-DQ and a twofold increase for HLA-DP when the IFN-gamma concentration was raised from 50 to 500 U/ml. When IFN-gamma was withdrawn from the cultures, HLA-DR mRNA and protein synthesis ceased--indicating the continuous need for IFN-gamma to maintain the HLA-DR synthesis in keratinocytes.
Nilsson
H
H
Department of Clinical Immunology, Karolinska Institute, Stockholm, Sweden.
Johansson
C
C
Sandberg
K
K
Funa
K
K
Alm
G V
GV
Scheynius
A
A
D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D005802:Genes, MHC Class II / Q000187:drug effects*; D006684:HLA-DR Antigens / Q000235:genetics*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D007633:Keratins / Q000032:analysis; D007700:Kinetics; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D011994:Recombinant Proteins; D012867:Skin / Q000187:drug effects / Q000276:immunology*; D014158:Transcription, Genetic / Q000187:drug effects*
D006684:HLA-DR Antigens; D012333:RNA, Messenger; D011994:Recombinant Proteins; D007633:Keratins; D007371:Interferon-gamma; D004247:DNA