Diversity of T-cell antigen receptor V beta gene utilization in advanced human atheroma.
Human atheromata contain T lymphocytes, but knowledge of the function and receptor specificity of these cells is limited. Immunohistochemical studies have established that T cells in advanced human carotid plaques express predominantly the alpha/beta form of the T-cell receptor (TCR). We then compared the use of variable region genes of the beta-chain (V beta) of the TCR for antigen by analysis of 14 carotid plaques and peripheral blood samples obtained at carotid endarterectomy. We used a direct approach that avoids isolation and culture of T cells. RNA extracted from lesions and peripheral blood mononuclear cells was reverse transcribed and amplified by polymerase chain reaction (PCR) to determine rearrangements of 18 V beta sequences. PCR products were visualized on Southern blots using a probe internal to the PCR primers. Input cDNA from lesions and peripheral blood was adjusted to yield equivalent signals for a conserved region of the TCR beta-chain to permit comparisons. As expected, utilization of TCR V beta genes in peripheral blood cells was nonselective: an average of 17 of 18 V beta regions yielded signals (n = 14). Frequency of variable-region gene usage in lesions and blood was highly concordant: of 252 sequences tested (14 samples, 18 sequences per sample), 240 were identified in peripheral blood versus 207 in plaques. V beta genes 10 and 11 were not expressed in plaques, a significant difference when compared with peripheral blood (P = .0001 by chi 2). However, the remaining 16 genes showed no significant differences. This analysis indicates that T cells generally express a diverse pattern of V beta genes within complex human atheroma.
Department of Medicine, Harvard Medical School, Boston, Mass. 02115.
S J
SJ
Swanson
A
A
Rosenzweig
J G
JG
Seidman
P
P
Libby
D001161:Arteriosclerosis / Q000276:immunology*; D015139:Blotting, Southern; D006801:Humans; D007124:Immunoenzyme Techniques; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D016133:Polymerase Chain Reaction; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
D007135:Immunoglobulin Variable Region; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta