Peripheral blood T lymphocytes in systemic @entity1333 : increased T cell receptor V beta 2 gene usage in microscopic XXXX .

@entity1 @entity573 @entity1333 @entity2612 @entity2883
Antigen recognition by T lymphocytes is mediated by cell surface receptors T cell specificity depends on the variable, diversity and junctional (VDJ) regions of the alpha and beta polypeptide chains of the T cell receptor (TCR). The expression of the variable region genes of the beta chain (V beta) has been analysed to study the involvement of peripheral blood T cells in systemic @entity1333 . RNA was extracted from peripheral blood lymphocytes of 12 @entity1 with microscopic @entity573 , 10 with @entity2883 , six with unclassified @entity1333 , and 28 healthy age- and sex-matched individuals. Complementary DNA was made from RNA and amplified by the anchored polymerase chain reaction (PCR) using redundant oligonucleotide primers for the TCR V beta genes. To determine if the dominant usage of a V beta gene family reflected the presence of particular T cell clones, cDNA was amplified with primers for the specific V beta gene family. The product was screened for sequence homogeneity by single-stranded conformational polymorphism (SSCP) and cloned to sequence the adjoining TCR (D beta) J beta region. A significant increase in the mean percentage expression of the V beta 2.1 gene was seen in @entity1333 @entity1 (11.4 + 1.0% (mean + s.e.m.)) compared with controls (6.6 + 0.6%; P < 0.003). The most marked increase was seen in microscopic @entity573 (13.9 + 1.7%; P < 0.0001). There were also increases in the expression of V beta 3, 13 and 14 in peripheral blood of @entity1333 @entity1 compared with controls. SSCP analysis of V beta 2.1 amplified products indicated the presence of oligoclonal bands in a smaller proportion of @entity1 (8/27) than controls (12/28). There was no strong evidence for the conservation of the TCR V beta 2.1 junctional region sequence data from a sample group of three @entity1 with oligoclonal bands. Thus, a subset of @entity1 with systemic @entity1333 , particularly those with microscopic @entity573 , have increased TCR V beta 2.1 gene expression in their peripheral blood T cell repertoire. As superantigens binding V beta 2.1 are postulated to activate T cells with diverse @entity2612 sequences, it is proposed that a superantigen is involved in the immunopathogenesis of @entity1333 .
