Responses to RhD autoantigen by PBMCs from patients with CLL with no clinical AIHA. Representative experiments showing proliferation by PBMCs from patients CLL1 (A), CLL2 (B), and CLL3 (C) after stimulation with a panel of overlapping 15-mer peptides spanning the sequence of the RhD protein (▪) or purified RhD protein (▨). Control unstimulated cultures were also included (□). Peptides are numbered 1 to 68 from the N-terminus. The dotted line indicates the level of response taken as representing a positive response (SI > 3). Error bars indicate SD.