title: T-cell nature of leukaemic cells in a case of Sézary's syndrome with 'null-cell' features.
abstract: alpha-naphthyl acetate esterase (ANAE) activity has been investigated in leukaemic cells from peripheral blood in a typical small-cell Sézary syndrome (SS) case in which cerebriform mononuclear cells failed to form E rosettes. The 'dot-like' ANAE positivity found in the majority of these neoplastic cells strongly supports a T-cell origin. In addition, a non-monocytic, non-B-cell nature of Sézary cells is indicated by the lack of Ia-like antigens. Finally, there is evidence of a distinct portion of Sézary cells simultaneously expressing ANAE activity and Fc IgM receptors.
mesh_terms: D004950:Esterases / Q000097:blood; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009284:Naphthols; D011961:Receptors, Fc / Q000302:isolation & purification; D012397:Rosette Formation; D012751:Sezary Syndrome / Q000097:blood* / Q000201:enzymology / Q000276:immunology; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000648:ultrastructure
chemical_list: D009284:Naphthols; D011961:Receptors, Fc; D004950:Esterases