Background: Buerger's disease, also known as Thromboangiitis Obliterans (TAO), is a progressive, inflammatory vascular disease with unknown etiology.
Objective: To address the degree of T cell immunosenescence in this inflammatory disease, the frequency of senescent T cells expressing CD57 and/or CD153 (CD30L) in patients with TAO.
Methods: In this study, nine male cigarette smoker patients with TAO, nine male healthy cigarette smokers, and nine male healthy non-smoker blood donors were enrolled. PBMCs were extracted from the blood of all participants and stored in liquid nitrogen before use. The percentages of senescent T cells were detected by flow cytometry. The results were analyzed using non-parametric statistical tests.
Results: The frequencies of senescent CD3+CD4+CD57+CD153+ and CD3+CD4+CD57-CD153+ T cells significantly increased in patients compared with the non-smoker controls (p=0.01 and p=0.04, respectively). The frequency of senescent CD3+CD4-CD57-CD153+ T cells was higher in patients compared with the smoker controls (p=0.02). In patients with TAO, CD57+CD153- cells were more frequent in CD3hiCD4- and CD3hiCD4+ T cells compared with the CD3loCD4- and CD3loCD4+ T cells (p=0.008 and p=0.0002, respectively). Conversely, the frequency of CD57-CD153+ T cells was significantly higher in CD3loCD4- T cells compared with the CD3hiCD4- T cells (p=0.004). The percentage of CD3+CD4+CD57+CD153- T cells correlated negatively with smoking level in smoker controls (p=0.02, Spearman r=-0.80).
Conclusion: Elevated frequencies of senescent CD4+CD57+CD153+ and CD4+CD57-CD153+ T cells in patients compared with non-smoker and smoker controls suggest the contribution of immunosenescence in TAO.
Keywords: CD57; CD153/CD30L; Cigarette Smoking; Immunosenescence; Thromboangiitis Obliterans.