Figure 5.

Mucosal and systemic memory-type responses following nasal priming and systemic boosting can be recalled by intranasal re-boost. Mice were primed intranasally (i.n.) with a mixture of NAP and CagA purified proteins and LTK63 adjuvant (NCLTK63) and boosted intramuscularly (i.m.) with a mixture of NAP and CagA purified proteins in MF59 adjuvant (NCMF59) and rested for 4 months before given either an i.n. or i.m. re-boost with NCLTK63 or NCMF59, respectively. All immunizations were performed at 2-week intervals. Serum and faecal pellets were collected 6 days after the final immunization in each group. Cells were prepared from mice killed 7 days after the final immunization for the ELISPOT assay. (a) Serum IgG titres. The results are shown as mean anti-NAP and anti-CagA serum titres from 10 mice as measured by a standard colorimetric ELISA. (b) Anti-NAP and anti-CagA antibody-secreting cells (ASC) in spleen (SP) and mesenteric lymph nodes (MLN) as measured by the ELISPOT assay. The ASC data are means of pools of two subgroups of five mice (total of 10 mice per group) + SD of the two pools of five mice per subgroup. The results are representative of two independent experiments with 10 mice in each group with similar results. (c) Mean anti-NAP IgA end-point titres in pools of faecal extracts from 10 mice + SD of five mice per subgroup as measured by a chemiluminescence ELISA. The results are representative of two independent experiments with similar results.