Abnormal T-cell expansion and V-gene usage in myasthenia gravis patients.
To determine the extent of V-gene heterogeneity of blood T lymphocytes in patients suffering from Myasthenia Gravis (MG), we used eight recently available monoclonal antibodies (MoAb), directed against different V alpha and V beta gene products of the variable part of the T-cell receptor (TCR), covering approximately 25% of the alpha/beta T cells in normal peripheral blood (PBL) of healthy individuals. Using a two-colour immunofluorescence method, we could calculate the expression of alpha/beta V segments within the two major T-cell subsets, CD4-/CD8+ and CD4+/CD8- lymphocytes. Twenty-seven per cent (4/15) of the MG patients had T cells showing signs of abnormal expansion. Furthermore, among these expanded T cells, a restricted V beta 12 gene expansion could be seen, in three out of four patients. No correlation between TCR V-gene usage and HLA haplotypes (HLA-A, -B, -DR and -DQ) could be seen. Our data suggest that the majority of MG patients have abnormally expanded T-cell clones. The relevance of these findings is discussed.
Grunewald
J
J
Department of Immunology, Karolinska Institute, Stockholm, Sweden.
Ahlberg
R
R
Lefvert
A K
AK
DerSimonian
H
H
Wigzell
H
H
Janson
C H
CH
D000911:Antibodies, Monoclonal; D005434:Flow Cytometry; D015332:Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D005796:Genes; D006801:Humans; D009157:Myasthenia Gravis / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016176:T-Lymphocyte Subsets / Q000276:immunology*
D000911:Antibodies, Monoclonal; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta