Local and systemic TCR V gene expression in advanced periodontal disease

Abstract

The aim of the present investigation was to study the expression of specific alpha/beta T cell receptor (TCR) gene products in relation to some microbiological and immunological features of advanced destructive periodontitis. 21 individuals with advanced periodontal disease (diseased group) and 16 age- and sex-matched healthy subjects (healthy group) were recruited. Following a clinical examination of the diseased group, the 3 deepest interproximal sites in the upper and lower premolar- or molar segments (i.e., 12 sites in each individual) were selected for further analysis. Samples from the subgingival microbiota were obtained from the pocket of the selected sites and were prepared for a microbiological examination. The gingival tissue at one of the selected sites was also biopsied. Each excised soft tissue specimen was divided into 2 equal portions. One portion of the biopsy was prepared for histometric and morphometric analyses. The 2nd portion was snap frozen and prepared for immunohistochemical analysis. A sample of peripheral blood was obtained from each individual of the diseased and the healthy group and prepared for immunohistochemical analysis. The selected sites of the diseased group harbored varying numbers of microorganisms which have been associated with periodontal disease. The excised gingival tissue contained inflammatory lesions with substantial numbers of lymphocytes and plasma cells including T- and B-cells and a TCR V alpha/beta gene repertoire dominated by Vbeta 17. The TCR profile of the lesion, however, differed markedly from that of the circulating blood of the diseased subjects. While only minor differences were observed between the blood samples of the diseased and the healthy subjects regarding the TCR genes, CD5, HLA-DR and CD5+CD19 positive cells occurred in higher proportions in the blood samples of the subjects susceptible to periodontal disease than in healthy controls. It may be suggested that (i) TCR V alpha/Vbeta expression in peripheral blood samples of subjects with periodontal disease does not differ from that of healthy individuals, and (ii) the periodontitis lesion expresses a unique TCR repertoire in which the Vbeta 17 gene dominates.

Efficient characterization of the TCR repertoire in lymph nodes by flow cytometry

“…However, it is well known that circulating lymphocytes do not exactly reflect the situation in tissues where pathologic lesions occur (6,17,23,33,37). Of note, investigations in sites other than peripheral blood have infrequently been conducted using flow cytometry (13,17,20,21,24,(32)(33)(34). As regards lymph nodes, only six studies primarily addressed this question, and these included few patients or used few anti-Vb mAbs (13,23,34,(36)(37)(38).…”

“…The TCR repertoire has been frequently studied in various diseases, but mainly in blood samples (6,14,15,19,(21)(22)(23)37,39), and more rarely in injured organs (3)(4)(5)(6)(7)(8)(9)(10)17,20,21,24,(32)(33)(34). However, it is well known that circulating lymphocytes do not exactly reflect the situation in tissues where pathologic lesions occur (6,17,23,33,37).…”

“…However, it is well known that circulating lymphocytes do not exactly reflect the situation in tissues where pathologic lesions occur (6,17,23,33,37). Of note, investigations in sites other than peripheral blood have infrequently been conducted using flow cytometry (13,17,20,21,24,(32)(33)(34).…”

“…It is important to note that using a four-color flow cytometer, the IOTest Beta Mark 1 kit and the anti-Vb6.7 mAb, it was possible to determine the distribution of 25 Vb families in only nine test tubes, for both CD41 and CD81 subsets, and to make results available on the same day the lymph node was excised. These mAbs have also been used to study T-cell Vb families by immunohistohistology on biopsies (3,17,33,40); however, the analysis was hardly reproducible or precise. Alternative techniques for TCR diversity exploration imply molecular approaches.…”

“…Flow cytometry also enabled T-cell repertoire analysis in tissues and organs. Expansions of several Vb families have been usually demonstrated in cases of autoimmune injury (18), infection (32,33), or tumor involvement (3,4,8,9,24,34), indicative of the presence of specific immune cells in pathologic lesions (18,35). In lymph nodes, such studies are rare, and have been only performed on small groups of patients with limited numbers of anti-Vb mAbs (23,34,(36)(37)(38).…”