Expression of MHC class II antigens in XXXX B-cell leukaemia and @entity1893 .

@entity1 @entity5 @entity1072 @entity4621 @entity6444 @entity865 @entity1893 @entity11155
In this review we have summarized our experiences of serological analysis of @entity11155 expression in @entity1 B cell malignant disease. Cells from a large number of cases of @entity1072 ( @entity6444 ) and @entity1893 ( @entity1893 ) have been examined for expression of class II antigens. Using a number of monoclonal antibodies which in some cases are specific for class II subregion products (DP, DQ and DR), MHC class II antigens were detected by indirect immunofluorescence and fluorescent activated cell sorter analysis in @entity6444 and by immunohistochemical staining in @entity1893 . At the cell surface in many cases of B cell malignant disease, products of the different class II subregion genes are non-coordinately expressed. The most commonly occurring pattern of non-coordinate expression of class II molecules is of expression of DP and DR antigens in the absence of detectable DQ expression. These findings are in contrast to normal B lymphocytes where DP, DQ and DR antigens are expressed together at the cell surface. There is considerable heterogeneity among cases comprising individual histopathological categories of B cell malignancy, and in many instances heterogeneous class II phenotypes are also found on cells from the same @entity5 . In @entity6444 , class II antigen expression is inducible in vitro by treating the cells with the @entity4621 TPA. @entity6444 cells treated with @entity865 have much increased levels of class II antigen expression at the cell surface and much increased steady state levels of class II specific mRNA transcripts detectable with complementary DNA probes. Aberrant class II antigen expression may be involved in the pathogenesis of B cell malignant disease.
