Table 1.

Protection against H. pylori challenge by a combination prime-boost strategy for mucosal immunization

First, second route of immunizationaMean from quantitative H. pylori cultureb(CFU/ml)P valuec
p.o., p.o.3770.0017
p.o., i.n.8580.0065
p.o., r.1,5900.0049
i.n., i.n.790.0003
i.n., p.o.1,2930.0017
i.n., r.6500.0007
r., r.3940.0014
r., p.o.4280.0027
r., i.n.2330.0037
All14,217
  • a Weekly immunizations were given on days 0, 7, 14, and 21 by either the p.o. (50 μl of soluble antigen delivered by pipette into the buccal cavity), the i.n. (5 μl of soluble antigen delivered to each external naris of unanesthetized mice), or the rectal (r.) (25 μl of soluble antigen delivered with an olive-tipped catheter directly into the rectum) route. The number of booster doses given by the second route specified was 3 (does not apply to sham-immunized controls). Sham-immunized control animals (n = 15) received LT alone by either the p.o., i.n., or rectal route (n = 5/route), and results were pooled for this analysis (“All”).

  • b Quantitative H. pylori culture was performed on homogenized stomach tissue (one-fourth of the antral tissue specimen) harvested at the time of termination (2 weeks postchallenge). Results are expressed as geometric means of CFU per milliliter per biopsy section for each of 10 mice immunized with rUre plus LT and each of 15 control mice sham-immunized with LT.

  • c By the Wilcoxon rank sum test. Values are relative to those for the LT sham-immunized control group.