Fig. 2.

Immunologic activity of OVA persists in dendritic cells in vitro for several weeks after antigen uptake. (A, Left) Fluorescence-activated cell sorter plots showing the expression levels of CD11c and I-A^b on BMDC-OVA cells cultured in vitro for 1, 7, 14, or 21 d. (A, Right) K^b/SIINFEKL presentation by BMDC-OVA cells in culture 7 d after refeeding with OVA on day 8 (black bars) or day 18 (gray bars) of culture. (B) Antigen persistence in BMDC-OVA cells as tested by the B3Z assay at various time points indicated. **P < 0.01, ***P < 0.001. (C) OVA protein or fragments and β-actin were detected by immunoblotting in cultured BMDC-OVA cells at time points indicated. (D) Duration of K^b/SIINFEKL presentation at time points indicated by BMDC pulsed with SKL8 (SIINFEKL) or SHL18 (LEQLKSIINFEHLKEWTS) on day 0. **P < 0.01, ***P < 0.001. Error bars indicate mean ± SD. The experiments were repeated three to five times.