Expression of CII TA gene in five human malignant hematological cell lines and its significance.
The role of MHC class II transactivator (C II TA) in constitutive or IFN-gamma inducible expression of HLA molecules in human malignant hematological cell lines was investigated. The expression of HLA molecules and C II TA protein was detected by Western blot, immunohistochemistry and flow cytometry. The expression of C II TA gene was determined by RT-PCR. The capability of peripheral blood T cell reaction stimulated by tumor cells was monitored by mixed lymphocyte reaction. It was found that the HLAII-positive tumor cells expressed the C II TA quite well, and the expression of HLA I + II was increased in the tumor cells with constitutive or inducible expression of C II TA after induced by IFN-gamma. The tumor cells which did not express C II TA after induced by IFN-gamma were not response to the expression of HLA II promoted by IFN-gamma. It suggests a correlation between the inability of some malignant hematological cell lines in response to IFN-gamma for HLA expression and the deficiency in the inducible expression of C II TA, indicating C II TA might take part in the regulation of HLA I + II expression in the tumor cells, which might play an important role in tumor immunologic escape.
You
Yong
Y
Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
Zou
Ping
P
Guo
Rong
R
D000818:Animals; D005802:Genes, MHC Class II / Q000235:genetics; D018922:HL-60 Cells; D006680:HLA Antigens / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D020014:K562 Cells; D007938:Leukemia / Q000378:metabolism* / Q000473:pathology; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics; D020298:U937 Cells
D006680:HLA Antigens; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D015534:Trans-Activators; D007371:Interferon-gamma