Anti-CD3ε PEBLs downregulate TCRαβ. (A) TCRαβ expression in GFP-positive T lymphocytes 5 to 9 days after PEBL transduction. Mean (± standard deviation [SD]) is shown for cells transduced with GFP only (“Control”; n = 25), PEBL2 (n = 4), and PEBL5 (n = 18); other data represent results of 1 or mean of 2 experiments. (B) Flow cytometric dot-plots illustrate TCRαβ downregulation in T lymphocytes compared with cells transduced with GFP only. (C) CD3/TCRαβ expression in Jurkat cells transduced with PEBL after long-term culture; Control, cells transduced with GFP alone. (D) Collective results of CD3/TCRαβ expression in long-term cultures of T lymphocytes (with 200 IU/mL IL-2) or Jurkat cells. Symbols indicate persistence of more than 90% reduction of surface CD3/TCRαβ in GFP⁺ transduced cells.