Altered T cell homeostasis in chronic hepatitis C virus (HCV) infection has been demonstrated. However, it is unknown if fibrosis is associated with more perturbed T cell homeostasis in chronic HCV infection. The aim of the present study was to examine and compare T cell subsets including recent thymic emigrants (RTE), naive, memory, senescent, apoptotic and IL-7 receptor α (CD127) expressing CD4+ and CD8+ T cells as well as telomere length and interferon-γ production in HCV-infected patients with (n=25) and without (n=26) fibrosis as well as in healthy controls (n=24). Decreased proportions of CD4+ and CD8+ RTE were found in HCV-infected patients, especially in HCV-infected patients with fibrosis (14.3% (9.7-23.0) and 28.8% (16.1-40.5), respectively) compared to healthy controls (24.2% (16.3-32.1), P=0.004, and 39.1% (31.6-55.0), P=0.010, respectively). Furthermore, HCV-infected patients with fibrosis presented with a higher proportion of CD4+ T cells expressing CD127 compared to HCV-infected patients without fibrosis (88.4% (84.5-91.0) vs. 83.8% (79.9-86.8), P=0.016). Thus, impaired thymic output in HCV infection was found, and high proportion of CD127+ T cells may illustrate a compensatory mechanism to preserve T cell counts. This article is protected by copyright. All rights reserved.
Scandinavian Journal of Immunology, 2013, Vol 78, Issue 4, p. 378-386