(A) The normal Vβ spectratype pattern consists of 6 to 8 bands and shows a Gaussian distribution in which the density of bands is generally higher in the middle part of the spectratype. Contracted spectratypes consisting of 1 to 4 peaks suggest the presence of a monoclonal (1 dominant peak) or oligoclonal (2-4 peaks) T-cell population. (B) Reversion of the T-cell repertoire to “normal” in an ITP patient after rituximab therapy. Several monoclonal (eg, VB 17, VB 18) or oligoclonal baseline patterns (eg, VB 1, VB 3, VB 5, VB 6, VB 9) turn to polyclonal after the B-cell–depleting therapy. Shown are the CDR3 size length (40 amino acids) in x-axis versus the relative fluorescence intensity in y-axis.