Specific anti-CXCL4L1 monoclonal antibody blocks CXCL4L1's biologic activity. (A) The specific anti-CXCL4L1 monoclonal antibody (Mab-L1) detects specifically proteins possessing His67. Conditioned media of HEK293T expressing CXCL4, CXCL4L1, or mutants were tested with CXCL4-ELISA (Mab-L4) or with a specific CXCL4L1-ELISA (Mab-L1). (B) Effect of Mab-L1 (10 μg/mL) on the proliferation of BAEC treated or not with rCXCL4 (5 μg/mL) or rCXCL4L1 (0.2 μg/mL). Mab-L4 and unrelated Immunoglobulin G were used as controls.