Elevated CCL5 expression correlates with disease activity. (A) Correlations between serum CCL5 and CCL5 in the bone marrow of patients with matched samples (n = 20). (B) Correlation between CCL5 levels in bone marrow plasma and IgM levels. (C) Correlation between CCL5 levels in serum and degree of bone marrow involvement by lymphoplasmacytic cells. (D) Immunohistochemical staining of CCL5 (brown) in bone marrow specimens of 3 healthy donors (NM1-NM3) and 4 WM patients (WM1-WM4) was performed using anti-CCL5 mAb as described in “Methods.” Images shown are original magnification ×400.