title: Immunophenotypic identification of Sezary cells in peripheral blood.
abstract: Despite anecdotal literature that Sezary cells express the CD4+ CD7- immunophenotype, no formal validation has been published establishing the use of this immunophenotype for clinical or experimental purposes. Consequently, the only method presently available for Sezary cell identification is nuclear contour analysis, a labor-intensive procedure not generally available at most major medical centers. In this study, the accuracy of CD4+ CD7- subset quantitation for the identification of Sezary cells was examined. The study found that the percentage of CD4+ CD7- cells is elevated in many Sezary syndrome/MF patients relative to normal, healthy individuals. In addition, CD4+ CD7- enumeration correlates with enumeration by nuclear contour analysis in most patients (11 of 15) with elevated CD4/CD8 ratios. The CD4+ CD7- subset also correlates with the expression of other aberrant immunophenotypes, such as CD3low or CD4low. Lastly, CD4+ CD7- subset quantitation correlates with the number of clonal T lymphocytes, as measured using V beta-specific T-cell receptor monoclonal antibodies. The study found this method to be exceptionally accurate, with two caveats: (1) the absence of an expanded CD4+ CD7- subset in patients with a normal CD4/CD8 ratio is uninformative; and (2) in approximately 25% of patients with an elevated CD4/CD8 ratio, the Sezary cells are CD7+.
authors.affiliation: Department of Pathology and Laboratory Medicine, Boston University Medical Center, MA 02118, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Bogen
authors.forename: D
authors.initials: D
authors.lastname: Pelley
authors.forename: M
authors.initials: M
authors.lastname: Charif
authors.forename: M
authors.initials: M
authors.lastname: McCusker
authors.forename: H
authors.initials: H
authors.lastname: Koh
authors.forename: F
authors.initials: F
authors.lastname: Foss
authors.forename: M
authors.initials: M
authors.lastname: Garifallou
authors.forename: C
authors.initials: C
authors.lastname: Arkin
authors.forename: D
authors.initials: D
authors.lastname: Zucker-Franklin
mesh_terms: D019011:Antigens, CD7 / Q000276:immunology*; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D015203:Reproducibility of Results; D012751:Sezary Syndrome / Q000097:blood / Q000473:pathology*; D012878:Skin Neoplasms / Q000097:blood / Q000473:pathology*
chemical_list: D019011:Antigens, CD7