Elevated levels of interleukin-12 and interferon-gamma in patients with human T lymphotropic virus type I-associated myelopathy

Relationship between the Clinical Efficacy of Pentoxifylline Treatment and Elevation of Serum T Helper Type 2 Cytokine Levels in Patients with Human T-lymphotropic Virus Type I-Associated Myelopathy.

“…In previous studies, we demonstrated that spontaneous production of inflammatory cytokines, such as IFN-y, TNF-oc and GM-CSF, but not IL-4, was simultaneously increased in cultured CD4+T cells of HAMpatients (15). Very recently, we demonstrated that both the serum and cerebrospinal fluid (CSF) level of IFN-y are elevated in HAM patients with elevated levels of serum IL-12, compared to patients with other neurological diseases including anti-HTLV-Iseropositive carriers (16). These data suggested that the Thl rather than Th2 cell population was dominant in peripheral blood CD4+ T lymphocytes of HAMpatients.…”

Low frequency of CD94/NKG2A+ T lymphocytes in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis, but not in asymptomatic carriers

“…However, levels of cytokines such as interleukin 2 (IL-2), IL-12, and IL-15, which have been shown to induce CD94/NKG2A expression in vitro, are significantly elevated in serum or PBMCs of patients with HAM/ TSP. [38][39][40] Furthermore, IL-15 inhibits AICD and stimulates the persistence of memory phenotype CD8 ϩ T cells. 41 Because the decrease in CD94/NKG2A ϩ T cells was mainly observed in ␥␦ T cells but not in ␣␤ T cells in HAM/TSP patients, it is possible that a high IL-15 level in HAM/TSP patients antagonizes the clearance of CD94/NKG2A T cells by AICD especially in the ␣␤ T-cell subset.…”

Animal models for human T-lymphotropic virus type 1 (HTLV-1) infection and transformation

“…IL-6 is a pleiotropic cytokine, acting as an acute-phase reactant that regulates differentiation, proliferation, and survival of a wide variety of cell types (Horn et al, 2000). IL-10 suppresses inflammatory responses, and regulates the growth of NK and T cells, and other cell types (Scholz et al, 1996;Tsuruma et al, 1996;Furuya et al, 1999;Carvalho et al, 2001). Thus, IL-10 could play an immunoevasion role for HTLV-1 infection.…”