CAL-101 inhibits signaling downstream of the BCR, CXCR4 and CXCR5. In vivo, CAL-101 reduces plasma chemokine levels, impairs AKT activation, and induces lymphocytosis in CLL patients. (A) CLL cells were activated with anti-IgM, or CXCL12, or CXCL13 in the presence or absence of CAL-101. Lysates were probed with phospho-specific antibodies to AKT and ERK1/2, and antibodies for total AKT, ERK1/2, and actin. (B-C) Plasma chemokine levels, AKT phosphorylation, and lymphocyte counts were evaluated in 12 CLL patients pretreatment and after 28 days on treatment with CAL-101. (B) The line graphs represent concentrations of CCL3, CCL4, and CXCL13 in plasma samples from CLL patients before and after 28 days of CAL-101 treatment. Displayed are the individual values. * represents the upper limit of normal. Chemokine values in the plasma from patients were significantly reduced by CAL-101. (C) The bar diagram represents the mean relative phospho-Akt^T308 fluorescence intensity values (adjusted for isotype control) derived from circulating CLL cells in patients undergoing CAL-101 treatment. Displayed are the means (± SEM). Akt phosphorylation in CLL cells from patients was significantly inhibited by CAL-101. The line graphs indicate the absolute lymphocyte counts in patients with CLL undergoing CAL-101 treatment. Displayed are the individual values. * represents the upper limit of normal. Absolute lymphocyte counts were significantly increased by CAL-101.