In a Mayo Clinic study, the blood from 19 T-ALL patients were compared to 24 normal samples using a flow cytometric panel. While the normal samples all showed a “characteristic and reproducible” pattern of cellsurface expressed CD3 and TRBC1 positivity, the leukemic samples were either almost entirely TRCB1 positive or almost entirely negative, indicating T cell clonality. Analysis of cytoplasmic expression in 9 patient samples supported these findings.
