Sezary syndrome T-cell clones display T-helper 2 cytokines and express the accessory factor-1 (interferon-gamma receptor beta-chain)

Abstract

Sezary syndrome (SS) is a leukemic variant of low-grade cutaneous T- cell lymphomas (CTCLs). The clonal T cells in this lymphoproliferative disorder are poorly characterized. Using antibodies against the variable region of the T-cell receptor (TCR V alpha/beta), we identified four predominant T-cell clones (two V beta 8+ clones, one V beta 5.1+, and one V alpha 2(a)+) in peripheral blood mononuclear cells (PBMC) of SS patients. Their phenotype was CD3+, CD4+, CD5+, CD45RO+. Clonal T cells were purified, and cytokine transcription and secretion was analyzed by reverse transcriptase-polymerase chain reaction (RT- PCR) followed by hybridization with biotinylated probes and enzyme- linked immunosorbent assays (ELISAs). The interleukin-10 (IL-10) PCR product was cloned and sequenced and found to be identical to the published cDNA sequence. The presence of accessory factor-1 (AF-1, or interferon-gamma [IFN-gamma] receptor beta-chain) encoding mRNA was assessed by RT-PCR and immunostaining using serum of rabbits immunized with the extracellular domain of a recombinant human AF-1 protein followed by APAAP staining. Clonal T cells transcribe and secrete mainly T-helper 2 cytokines (IL-10, -5, and -13). mRNA from purified SS clones but not mRNA from SS total PBMC was positive for AF-1 in an agarose gel and/or after hybridization. AF-1 transcription was associated with membrane-bound immunoreactivity for AF-1 in SS clones. SS-derived T-cell clones display T-helper 2 cytokines. This weakens cell-mediated immunosurveillance, and explains the clinical and immunologic abnormalities in SS patients. The T-helper 2 cytokine spectrum of all clones investigated is associated with overexpression of AF-1. This suggests that AF-1 is a potential marker for these clones (and eventually other T-helper 2 lymphocytes) and might represent a target for treatment of the disease.

The diagnosis of Sézary syndrome on peripheral blood by flow cytometry requires the use of multiple markers

“…An interesting approach is the evaluation of CD27 expression which was shown to differentiate between SS and patients with chronic inflammatory diseases. 39 Finally, patients with SS could be identified by their T-helper 2 cytokine profile, 40 DNA ploidy analysis 41 or by gene profiling analysis. 42 Over the last decades many monoclonal antibodies detecting T-cell antigens were tested in SS.…”

The use of anti‐T‐cell receptor‐Vβ antibodies for the estimation of treatment success and phenotypic characterization of clonal T‐cell populations in cutaneous T‐cell lymphomas

“…The mAbs were specific for families of TCR-chain variable regions, indicating clonality of a T-cell population in lymphomas (Clark et al, 1986). After using mAbs on CTCL biopsies, clonal populations in the peripheral blood of SS patients was indicated (Charley et al, 1990) and confirmed by several groups (O'Grady et al, 1990;Heald et al, 1994;Kuchnio et al, 1994;Bogen et al, 1996;Dummer et al, 1996) In order to monitor treatment responses, we studied the level of clonal T cells in CTCL patients and the clinical follow-up during different therapies. We found an association between CD4 + Vb + clonal levels and the clinical development during treatment.…”

“…In recent studies, the expression of T-cell surface markers in CTCL was investigated and revealed abnormal patterns in the late stages of disease (CD2 + , CD3 + , CD4 + , CD5 + , CD45RO + , CD45RA -) (Dummer et al, 1996;Jakob et al, 1996;Karenko et al, 2001). In our study, phenotypic analysis of the clonal T cells demonstrated them to be predominantly CD3 + , CD5 + , CD7 + , CD28 + , CD80 -, CD80 + , HLA class I + and heterogeneous for HLA-DR.…”

Cutaneous malignant lymphomas: Update 2006

“…Der Sézary-T-Zell-aktivierende-Faktor (SAF) wurde als Chlamydien-assoziiertes Protein nachgewiesen, das möglicherweise eine Rolle in der Pathogenese der CTCL spielt, vor allem bei Formen mit Erythrodermie [22], ein Befund , der jedoch von anderen Arbeitsguppen nicht bestätigt werden konnte [23]. [26]. Eines der Zytokine, das eine bedeutende Rolle spielt, ist IL-10, das indirekt über eine Herunterregulierung der Antigenpräsentation und akzessorischer Zellfunk-tionen von Monozyten, Makrophagen, Langerhans-Zellen und dendritischen Zellen eine Antigen-spezifische T-Zell-Aktivierung verhindert.…”