Class II major histocompatibility complex antigen expression and cellular interactions in XXXX of @entity2743 .

@entity1 @entity2743 @entity1669 @entity379 @entity8426 @entity1374
Class II major histocompatibility complex (MHC) antigens have been demonstrated on the surface of thyroid epithelial cells (thyrocytes) from @entity1 with @entity1669 . The present study was designed to investigate how the expression of class II MHC antigens is involved in autoimmune processes in @entity2743 by studying cellular interactions among thyrocytes, lymphocytes within @entity1374 ( @entity1374 ), and peripheral blood (PB) lymphocytes. Thyrocytes were prepared by collagenase digestion, and T or non-T cells were separated by E-rosette formation. Thyrocytes were cocultured in the presence or absence of @entity379 , and the expression of HLA-DR antigens on cultured thyrocytes was examined by an indirect immunofluorescence method using monoclonal anti-HLA-DR antibody and monoclonal anti-HLA-DQ antibody. The cellular interactions were assessed as the proliferative response of T cells to autologous stimulators, such as thyrocytes or lymphocytes. Expression of HLA-DR antigens on thyrocytes after culture for 18 h in the absence of @entity379 was found in two thirds of the @entity1 with @entity2743 studied (n = 18). @entity379 induced and maintained the expression of HLA-DR antigens on thyrocytes. The percentages of HLA-DR+T cells were significantly higher among @entity8426 cells than among PB-T cells [32.6 +/- 12.4% (+/- SD) vs. 12.2 +/-5.0%; n = 18; P less than 0.01]. Thyrocytes from Graves' @entity1 induced proliferation of both autologous PB-T cells and @entity8426 cells, and @entity8426 cells stimulated proliferation of autologous PB-T cells. In conclusion, @entity379 induces HLA-DR antigen expression on thyrocytes from @entity1 with @entity2743 , and these cells induce proliferation of autologous T cells, which may, in turn, act on thyrocytes to perpetuate the process.
