Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2002-4-23
pubmed:abstractText
HLA-G is a nonclassical MHC molecule with highly limited tissue distribution that has been attributed chiefly immune regulatory functions. Glioblastoma is paradigmatic for the capability of human cancers to paralyze the immune system. To delineate the potential role of HLA-G in glioblastoma immunobiology, expression patterns and functional relevance of this MHC class Ib molecule were investigated in glioma cells and brain tissues. HLA-G mRNA expression was detected in six of 12 glioma cell lines in the absence of IFN-gamma and in 10 of 12 cell lines in the presence of IFN-gamma. HLA-G protein was detected in four of 12 cell lines in the absence of IFN-gamma and in eight of 12 cell lines in the presence of IFN-gamma. Immunohistochemical analysis of human brain tumors revealed expression of HLA-G in four of five tissue samples. Functional studies on the role of HLA-G in glioma cells were conducted with alloreactive PBMCs, NK cells, and T cell subpopulations. Expression of membrane-bound HLA-G1 and soluble HLA-G5 inhibited alloreactive and Ag-specific immune responses. Gene transfer of HLA-G1 or HLA-G5 into HLA-G-negative glioma cells (U87MG) rendered cells highly resistant to direct alloreactive lysis, inhibited the alloproliferative response, and prevented efficient priming of cytotoxic T cells. The inhibitory effects of HLA-G were directed against CD8 and CD4 T cells, but appeared to be NK cell independent. Interestingly, few HLA-G-positive cells within a population of HLA-G-negative tumor cells exerted significant immune inhibitory effects. We conclude that the aberrant expression of HLA-G may contribute to immune escape in human glioblastoma.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
168
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4772-80
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11971028-Brain, pubmed-meshheading:11971028-Brain Neoplasms, pubmed-meshheading:11971028-Cell Line, Transformed, pubmed-meshheading:11971028-Cells, Cultured, pubmed-meshheading:11971028-Cytotoxicity, Immunologic, pubmed-meshheading:11971028-Cytotoxicity Tests, Immunologic, pubmed-meshheading:11971028-Glioma, pubmed-meshheading:11971028-HLA Antigens, pubmed-meshheading:11971028-HLA-G Antigens, pubmed-meshheading:11971028-Histocompatibility Antigens Class I, pubmed-meshheading:11971028-Humans, pubmed-meshheading:11971028-Isoantigens, pubmed-meshheading:11971028-Lymphocyte Activation, pubmed-meshheading:11971028-RNA, Messenger, pubmed-meshheading:11971028-T-Lymphocytes, pubmed-meshheading:11971028-Transcription, Genetic, pubmed-meshheading:11971028-Transfection, pubmed-meshheading:11971028-Tumor Cells, Cultured, pubmed-meshheading:11971028-Tumor Escape
pubmed:year
2002
pubmed:articleTitle
A functional role of HLA-G expression in human gliomas: an alternative strategy of immune escape.
pubmed:affiliation
Department of Neurology, Medical School, University of Tübingen, Tübingen, Germany. heinz.wiendl@uni-tuebingen.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't