High expression of CD59 and CD55 on benign and malignant plasma cells

In summary, our study reveals a relatively high expression of complement regulatory proteins on the surface of plasma cells, which appears to be a constitutive feature of these cells, rather than a specific change induced by a malignant state. Further efforts will aim at establishing a correlation between CD55 and CD59 expression levels and in vitro and in vivo resistance to rituximab.