Changes in tumor cell motility in response to anti-CD151 antibodies were determined by analyzing the formation of metastatic colonies in the chorioallantic membrane. (A) The inhibition of tumor cell dissemination in the presence or absence of anti-CD151 antibodies (1A5, 8C3, 14A2.H1, and 11G5A) was compared to the dissemination in the absence of tumor targeting antibodies (untreated) or a control IgG. Images were taken after 4 days of treatment with 0.5, 5, or 20μg or antibody (A) and the number of colonies with motile tumor cells were quantified (B). N ≥ 5 with experiments performed in duplicate.