Sézary syndrome patients demonstrate a defect in dendritic cell populations: effects of CD40 ligand and treatment with GM-CSF on dendritic cell numbers and the production of cytokines.

Sézary syndrome (SzS) is an advanced form of cutaneous T-cell lymphoma associated with involvement of the peripheral blood by malignant T cells. The disease is defined by impaired cell-mediated immunity and the production of interferon-gamma (IFN-gamma) and interleukin-2 (IL-2), possibly as a result of deficient IL-12 production. To understand the mechanism of this impairment, we examined the composition and function of dendritic cells and monocytes in the blood of SzS patients with different levels of peripheral blood tumor burden.

Synergistic enhancement of cell-mediated immunity by interleukin-12 plus interleukin-2: basis for therapy of cutaneous T cell lymphoma.

Cutaneous T cell lymphoma is a clonally derived, skin-invasive malignancy of CD4+ T lymphocytes with the phenotype of mature helper T cells. Previous work has demonstrated that the Sézary form, or typically leukemic form of cutaneous T cell lymphoma, is characterized by prominent immunologic defects, including depressed cell-mediated immunity associated with marked defects in the production of interleukin-12 and other type 1 helper T cell cytokines. Recent clinical trials with recombinant human interleukin-12 for cutaneous T cell lymphoma have demonstrated that it is a potent therapeutic agent, which induces cytotoxic T cell responses.