Cutaneous T-cell lymphoma: Utility of antibodies to the variable regions of the human T-cell antigen receptor

Background: The clonotypic 90 kd Ti heterodimer of the human T-cell antigen receptor is composed of two distinct chains (αβ or rarely τδ) that result from the recombination of variable (V), constant, joining, and, in the case of β chains, additional diversity regions. Objective: The variable region expression of human cutaneous T-cell lymphoma (CTCL) was studied. Methods: Biopsy specimens from 13 patients with CTCL (7 plaque, 3 tumor stage, 3 Sézary syndrome) were examined immunohistochemically by a panel of seven commercially available monoclonal V-region antibodies. Results: Two patients had significant anti-V-region staining. One patient with Sézary syndrome had two lesions, subjected to biopsy 4 months apart, that reacted with βV5 (a), a specificity previously documented by flow cytometry of leukemic cells. A patient with plaque-stage CTCL, negative for T-cell gene rearrangement by Southern blot, demonstrated reactivity with βW5(c) largely limited to epidermotropic lymphocytes. Conclusion: Panels of V-region antibodies should be useful reagents for diagnosis and follow-up of CTCL.