Fig. (1) Cluster of differentiation positivity of subclones from TKS cells. Two TKS subclones (type 1&2) were isolated by repeated limiting dilution in 96-well micro-culture plates. The phenotypes of these clones were CD15+ CD30+ CD19+ CD20+ (type 1) and CD15+ CD30+ CD19– CD20+ (type 2). Type 1 TKS subclone (TKS-1) reacted with following antibodies against surface antigens: Ig light chain kappa, HLA-DR, Leu 10, Leu 12 (CD19), Leu 16 (CD20), Leu M1 (CD15), and Ki-1 (CD30). These cells were unreactive to antibodies OKM1 (CD11b), Leu M2, Leu M3 (CD14), Leu M4, or to T cell surface or natural killer cell antigens. Numbers in parentheses are MFI values. Dot plots show representative flow cytometry data.