Ultrastructure of medullary thymic epithelial cells of autoimmune regulator (Aire)-deficient mice.
The significance of the autoimmune regulator (Aire) transcription regulator in establishing central tolerance has recently been elucidated in great detail. Still, the role of Aire in medullary thymic epithelial cell (mTEC) physiology is not fully understood. To shed more light on this issue, we studied the ultrastructure of mTECs in Aire-deficient thymus. We show that all types of mTECs show ultrastructural signs of activation and increased intracellular traffic, which suggests that in the absence of Aire their physiology is impaired. Type 6 'large' mTECs are fully developed in Aire-deficient mice and more frequent than in the normal thymus. The frequency of type 5 'undifferentiated' mTECs is also increased. Collectively, our results suggest that the role of Aire in the physiology of mTECs could be more profound and not restricted only to the presentation of self-tissue-restricted antigens and/or apoptosis of end-stage fully mature cell types.
Milićević
Zivana
Z
Faculty of Medicine, Institute of Histology and Embryology, University of Beograd, Beograd, Serbia.
Milićević
Novica M
NM
Laan
Martti
M
Peterson
Pärt
P
Kisand
Kai
K
Scott
Hamish S
HS
Westermann
Jürgen
J
D000818:Animals; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure*; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008854:Microscopy, Electron; D021381:Protein Transport; D013950:Thymus Gland / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure*; D014157:Transcription Factors / Q000172:deficiency / Q000276:immunology / Q000378:metabolism*; D000096927:AIRE Protein
D014157:Transcription Factors; D000096927:AIRE Protein