CD81 and neuroblastoma: Using confocal imaging, we confirmed that LGALS3BP co-localizes with the exosome markers CD-63 and CD-81 (Figure 1D and Figure S1A) and its mature form is enriched in exosomes/EVs isolated from SKNAS but not hNB neuroblastoma cells (Figure 1E and Figure S1B), providing an opportunity for specific targeting with 1959 antibody (Figure 1F).