TH2 CYTOKINE MESSENGER-RNA EXPRESSION IN SKIN IN CUTANEOUS T-CELL LYMPHOMA

We have previously demonstrated that peripheral blood mononuclear cell s from patients with Sezary syndrome, the leukemic form of cutaneous T -cell lymphoma which is accompanied by erythroderma and lymphadenopath y, have a Th2 cell cytokine [interleukin 4 (IL-4) and interleukin 5] p roduction pattern. In this study, we extend these observations to demo nstrate a correlation of the presence of a Th2 cytokine pattern with a malignant T-cell clone in different stages of cutaneous involvement a mong patients with cutaneous T-cell lymphoma (CTCL). Skin biopsies wer e obtained from 12 CTCL patients with various disease stages (three pa tch, three plaque, six tumor), three patients with parapsoriasis, four patients with inflammatory dermatoses, including two psoriasis and tw o lichen planus, and 12 normal controls. Total RNA was extracted, reve rse transcribed, and PCR amplified with IL-2, IL-4, IL-5, interferon g amma (IFN-gamma), and beta-actin oligonucleotide primers. Although all skin specimens tested had detectable IL-2 and IFN-gamma mRNA, only sp ecimens from patients with CTCL or parapsoriasis had demonstrable IL-4 and/or IL-5 mRNA. Specifically, IL-5 mRNA was detected in skin biopsi es from five of six tumor-stage CTCL, two of three plaque-stage CTCL, one of three patch-stage CTCL, and 1 of 3 parapsoriasis patients, wher eas IL-4 mRNA was demonstrated to be present in five of six tumor-stag e, one of three plaque stage, none of three patch-stage CTCL, and none of three parapsoriasis patients. These results indicate that in all s tages of cutaneous involvement of CTCL, encompassing patch stage throu gh tumor stage, IL-4 and IL-5 mRNA is variably detectable. In tumor-st age skin lesions, typically characterized by a dense dermal infiltrate of malignant T cells, Th2 cytokine mRNA is virtually always detectabl e. The ability to detect Th2 cytokine mRNA in the skin of patients wit h CTCL supports our previous findings that the malignant T cells in CT CL possess a Th2-helper cell phenotype.