Total amount: € 0,00
Indexed/Abstracted in: BIOSIS Previews, Current Contents/Clinical Medicine, EMBASE, PubMed/MEDLINE, Science Citation Index Expanded (SciSearch), Scopus
Impact Factor 1,632
Profumo E. 1, Buttari B. 1, Tosti M. E. 2, Tagliani A. 3, Capoano R. 4, D’amati G. 5, Businaro R. 3, Salvati B. 4, Riganò R. 1
1 Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Rome, Italy;
2 National Centre of Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Rome, Italy;
3 Department of Human Anatomy, La Sapienza University, Rome, Italy;
4 Department of Surgical Sciences, La Sapienza University, Policlinico Umberto I, Rome, Italy;
5 Department of Experimental Medicine, La Sapienza University, Rome, Italy
Aim: Inflammation plays a crucial role in the progression of atherosclerotic plaques. The aim of the present study was to investigate phenotypic and functional characteristics of plaque-infiltrating T lymphocytes associated with a complicated phenotype of carotid atherosclerotic lesions.
Methods: Atherosclerotic plaques were obtained from 17 patients undergoing carotid endarterectomy and cultured to isolate infiltrating T lymphocytes. Blood samples were obtained from patients and from 20 sex- and age-matched healthy subjects. The presence of lymphocytes (CD3+ cells) within atherosclerotic plaques was determined by immunohistochemistry. Phenotypic characteristics and intracellular cytokine expression of plaque-infiltrating and circulating T lymphocytes were determined by flow cytometry. Cytokine levels in supernatants from infiltrating T cell cultures were evaluated by enzyme-linked immunosorbent assay.
Results: A higher number of CD3+ cells was detected in complicated than in uncomplicated plaques. Complicated plaques had higher percentages of tumor necrosis factor (TNF)-α- and interferon (IFN)-γ- positive cells than uncomplicated ones, especially in CD4+ subpopulation. In patients the percentages of TNF-α-positive cells were higher in infiltrating than in circulating lymphocyte samples. Intracellular TNF-α, IFN-γ, interleukin (IL)-4 and IL-10 expression resulted higher in circulating lymphocyte samples from patients than in those from healthy subjects. Supernatants of infiltrating T cell cultures from complicated plaques showed higher levels of TNF-α and lower levels of IL-4 than those from uncomplicated plaques.
Conclusion: Our data provide new information on the presence of increased percentages of pro-inflammatory T lymphocytes in complicated plaques with respect to uncomplicated ones and support the concept of the key role played by activated T cells in the progression of atherosclerotic lesions.