Each antigen (Ag)-driven immune reaction begins with Ag recognition by T- lymphocytes through a surface molecular structure and T-cell antigen receptor (TCR). TCR is a protein heterodimer, composed of an α and a β chain (αβ+ T-cells) or of a γ and a δ chain (γδ+ T-cells); each TCR chain is composed of two subunits the constant (C) region and the variable (V) region, whose combination is responsible, at least in part, for Ag specificity of each T-cell. Immune reactions toward known (e.g. tuberculosis) or unknown (e.g. sarcoidosis). Ags play an important role in the pathogenesis of many pulmonary disorders. The study of TCR may be performed at DNA, RNA and protein levels, applying molecular biology techniques. Using this molecular approach, it has been demonstrated, for example, that subgroups of patients have increased proportions of lung and/or blood T-cells bearing TCR with certain V regions of the αβ+ T-cells or of the γδ+ T-cells, suggesting that these cells were reacting toward antigenic stimuli. Similar results were obtained in tuberculosis, where an increase in γδ+ T-cells have been observed in peripheral blood of some patients. In asthma and in lung cancer a characterisation of TCRs of T-cells reacting to the involved allergens or to the tumour-associated Ags is still lacking, although animal studies show a selection of allergen-specific TCRs among the airway T-cells, and the ability of tumour-infiltrating γδ+ T-cells to kill cancer cells. Thus the characterisation of the repertoire of TCRs in pulmonary disorders may be relevant in the definition of key steps of the immunopathogenesis and in the development of new markers of activity of disease, and perhaps it may be able to unveal the etiology and to focus our attention on possible target for treatment of some pulmonary disorders.
|Number of pages||8|
|Journal||Monaldi Archives for Chest Disease - Cardiac Series|
|Publication status||Published - 1994|
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Pulmonary and Respiratory Medicine