Figure 5.

Vav controls phagosomal pH and antigen degradation. (A) Phagosomal pH was measured in BMDCs using latex beads coupled with pH-sensitive FITC and pH-insensitive Alexa Fluor 647. DCs were loaded with beads for 30 min, washed, and cultured for the indicated time points before analysis by FACS. For analysis, cells that had internalized equal numbers of beads (based on Alexa Fluor 647 MFI) were gated and analyzed for FITC MFI. Data represent the relative fold change in FITC MFI over time. (B) Antigen degradation in phagosomes was monitored using latex beads covalently coupled to OVA. DCs were loaded with beads for 30 min, washed, and cultured for the indicated time points. Beads were then recovered by lysing the cells and stained with anti-OVA antibodies before FACS analysis.