Fig. 3

The N terminus of ANXA2 is necessary and sufficient for TLR2 signaling and cross-priming. a Peptides derived from the N-terminus of ANXA2 (ANXA2-OVA, the first 36 N-terminal aa from ANXA2 fused to SIINFEKL; ANXA2(ΔN15)-OVA, ANXA2 N terminal residues 16–36 fused to SIINFEKL; scrambled ANXA2-OVA, the first 36 N-terminal residues from ANXA2 randomly ordered and fused to SIINFEKL) were pulsed onto HEK-Blue human TLR2 cells and secreted alkaline phosphatase was measured. The average absorbances at 640 nm from three replicate experiments were 46.7, 5.6, and 2.5 for ANXA2-OVA, ANXA2(ΔN15)-OVA, and scrambled ANXA2-OVA, respectively. b Naïve wildtype mice were vaccinated with the sequential daily injection protocol as described in Fig. 2, with OVA plus or minus ANXA2-OVA fusion peptide and derivatives. From three replicate experiments, the average frequencies of dextramer-binding CD8α + cells were 8.6 %, 3.2 % or 2.1 % from mice respectively immunized with ANXA2-OVA, ANXA2(ΔN15)-OVA, or scrambled ANXA2-OVA. Error bars are ± SEM, and lines represent an unpaired t-test p <0.05