Impaired expression of MHC class I molecules on mouse testicular germ cells is mainly caused by the post-transcriptional mechanism.
In this study, we examined expression of the major histocompatibility complex (MHC) class I molecules and of the mRNAs for MHC class I-mediated antigen presentation machinery molecules in highly purified C57BL/6 mouse testicular germ cells. Although H2 class I molecules were not detected on the cell surface, small amounts of the molecules were detected inside the cells by flow cytometric and immunoprecipitation analyses. Interferon (IFN)gamma treatment did not affect expression of the molecules on the surface by flow cytometric analysis. In addition, expression of mRNAs for MHC class I-mediated antigen presentation machinery molecules in the germ cells was analyzed by reverse transcription-polymerase chain reaction analysis. The faint constitutive expression of mRNAs for H2-K, beta2-microglobulin (beta2m), tapasin, and calnexin was observed in the cells. IFNgamma treatment up-regulated expression of mRNAs for H2-K, beta2m, TAP1 (a peptide transporter), and LMP2 (a proteosomal subunit). These findings indicate that impaired expression of MHC class I molecules on the cell surface of mouse testicular germ cells is mainly caused by the post-transcriptional regulatory mechanism.
Hotta
C
C
Department of Immunology and Parasitology, Yokohama City University School of Medicine, Yokohama, Japan.
Nagata
T
T
Nakazawa
M
M
Fujimaki
H
H
Yoshinari
M
M
Minami
M
M
D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D002462:Cell Membrane / Q000378:metabolism; D002469:Cell Separation; D002478:Cells, Cultured; D015870:Gene Expression; D006183:H-2 Antigens / Q000235:genetics; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D007371:Interferon-gamma / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger; D013094:Spermatozoa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D013737:Testis / Q000166:cytology
D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; D015395:Histocompatibility Antigens Class I; D012333:RNA, Messenger; D007371:Interferon-gamma