Similar to PMA, treating CLL B-cells with the TLR9 agonist CpG ODNs induces significant morphologic changes and phenotypic activation, as shown by increased cell surface expression of CD54, CD86, and HLA-DR and intense proliferation of allogeneic T-cells in mixed lymphocyte reaction (256). Here, TLR9 is linked to B-cell chronic lymphocytic leukemia.