Nurse-like cells show deregulated expression of genes involved in immunocompetence.

Chronic lymphocytic leukaemia (CLL) cells convert CD14(+) cells from patients into 'nurse-like' cells (NLCs). CLL cells can also convert CD14(+) peripheral blood mononuclear cells (PBMCs) from healthy donors into cells with morphological similarities to NLCs (CD14(CLL) -cells). However it is unclear whether only CLL cells induce this conversion process. This study showed that CD14(+) PBMCs from healthy donors could also be converted into differentiated cells (CD14(B) -cells) by non-malignant B-cells. In order to identify changes specifically induced by CLL cells, we compared gene expression profiles of NLCs, CD14(CLL) -cells and CD14(B) -cells. CD14(+) cells cultured with CLL cells were more similar to NLCs than those cultured with non-malignant B-cells. The most significant changes induced by CLL cells were deregulation of the antigen presentation pathway and of genes related to immunity. NLCs had reduced levels of lysozyme activity, CD74 and HLA-DR in-vitro while expression of inhibitory FCGR2B was increased. These findings suggest an impaired immunocompetence of NLCs which, if found in-vivo, could contribute to the immunodeficiency in CLL patients.