LeY has angiogenic properties and its effect is attenuated by rTMD1. (A-B) Chemotactic effect of LeY-PAA. Boyden chamber migration assay of HUVECs was performed. (A) Various concentrations of LeY-PAA were added to the bottom wells as chemoattractant, and migrated HUVECs were enumerated after 4 hours of incubation. Values are the mean ± SD (n = 5). *P < .05 and ***P < .001 compared with the vehicle control. (B) LeY-PAA was incubated with various concentrations of Pichia-expressed rTMD1 30 minutes before being added to bottom wells as chemoattractant. Values are the mean ± SD (n = 5), and similar results were obtained in at least 3 different experiments. *P < .05, **P < .01, and ***P < .001 compared with the control. ##P < .01 and ###P < .001 compared with the LeY-PAA. HPF indicates high-power field. (C-D) The effect of LeY Ab on tube formation. HUVECs were preincubated with various concentrations of LeY Ab or isotype-matched IgM 30 minutes before being placed on Matrigel. (C) Schematic presentation of tube structure on Matrigel after 6 hours of incubation. The magnification bar is 100 μm. (D) Statistical analysis of the total tube length. Mouse IgM (10 μg/mL) was used as isotype-matched control. The data are the mean ± SD (n = 3). **P < .01 and ***P < .001 compared with the IgM. Similar results were obtained in at least 3 different experiments.