HLA-DMB expression by thyrocytes: indication of the antigen-processing and possible presenting capability of thyroid cells.
Expression of HLA class II molecules on thyrocytes is a characteristic feature of autoimmune thyroid disease and may lead the thyroid cells to present autoantigens to CD4+ T lymphocytes. Since HLA-DM is a critical molecule in class II-restricted antigen processing and presentation, we assessed the expression of HLA-DMB, -invariant chain (Ii), class II transactivator (CIITA) and DRA in an untransformed, pure thyrocyte strain HTV-59A. Here we report that both HLA-DMB mRNA and the protein are expressed in thyrocytes and that CIITA expression is enhanced by interferon-gamma (IFN-gamma) treatment and occurs before DMB, Ii and DRA up-regulation, suggesting CIITA expression is a requirement for antigen processing in thyrocytes. These results indicate that thyrocytes are capable of antigen processing and possibly antigen presentation to T cells.
Wu
Z
Z
Department of Immunology, St Bartholomew's, London, UK.
Biro
P A
PA
Mirakian
R
R
Hammond
L
L
Curcio
F
F
Ambesi-Impiombato
F S
FS
Bottazzo
G F
GF
D017951:Antigen Presentation; D017920:Antiporters; D002352:Carrier Proteins / Q000096:biosynthesis; D027963:Chloride-Bicarbonate Antiporters; D015870:Gene Expression; D006681:HLA-D Antigens / Q000302:isolation & purification*; D000949:Histocompatibility Antigens Class II; D006801:Humans; D008565:Membrane Proteins / Q000096:biosynthesis; D009687:Nuclear Proteins; D000076988:Sulfate Transporters; D013961:Thyroid Gland / Q000166:cytology / Q000276:immunology*; D015534:Trans-Activators / Q000096:biosynthesis; D015854:Up-Regulation
D017920:Antiporters; D002352:Carrier Proteins; D027963:Chloride-Bicarbonate Antiporters; C416189:H2-M antigens; D006681:HLA-D Antigens; C084245:HLA-DM antigens; D000949:Histocompatibility Antigens Class II; C083728:MHC class II transactivator protein; D008565:Membrane Proteins; D009687:Nuclear Proteins; C081011:SLC26A3 protein, human; D000076988:Sulfate Transporters; D015534:Trans-Activators