Patients with ITP>65 had expanded CD21-CD24- and CD21-CD24++ naïve and memory IgMD+ B-cell populations compared to <i>the</i> HC>65 group.<h4>Conclusion</h4>These findings suggest that ageing induces modifications to the B-cell phenotype that are similar to those observed in patients with ITP, except for the expansion of the CD21-CD24- naïve B-cell subset, <i>which appears to be a characteristic of ITP shared with other autoimmune diseases.</i>. This evidence concerns the gene CR2 and autoimmune thrombocytopenic purpura.