Contribution of CLEC4M tandem neck region polymorphisms to VWF binding and internalization. (A) CLEC4M variable tandem repeat constructs (4, 6, and 9) were created. (B) A total of 293 cells were transiently transfected with constructs singly or in combinations, and CLEC4M expression was verified with flow cytometry. (C) Duplicate transfection conditions were exposed to VWF (1 U/mL) for 24 hours. Cells were washed and lysed, and levels of VWF in the cell lysate were quantified by ELISA. N = 6 to 8 independent experiments; ± SE, *P < .05; **P < .001.