Figure 8.

Monocytes bind to tumor cells via csMUC16-Siglec-9 interaction. Monocytes were purified from PBMC of healthy donors using the RosetteSep monocyte isolation kit (Stem Cell Technologies). The monocytes were labeled with Calcein AM and added to wells containing either csMUC16^pos-OVC or csMUC16^neg-OVC. After incubation and washing, the Calcein-labeled monocytes bound to the tumor cells were measured on a fluorescence plate reader. To demonstrate that binding was occurring via Siglec-9, matching Calcein AM-labeled monocytes were pre-treated with anti-Siglec-9 blocking antibody (Clone 191240, R&D Systems) prior to conducting the cell binding assay. Data shown is mean of three independent measurements.