Fig. 4: Rapid citrOgen modification to present E. coli O25b O-Ag.
A The CR rfb locus editing vector can be rapidly modified to insert the O25b rfb locus from EC958 (ST131 ESBL-producing strain) into the CR genome, generating CRECO25b. B Agglutination of EC958 and CRECO25b with polyclonal sera to O25b O-antigen. CRWT forms a tight pellet, indicating no agglutination of this strain. In control wells (PBS), all strains form tight pellets in the absence of agglutination. C At 8 dpi following oral gavage, faecal CFUs are not significantly lower in CRECO25b+pespO compared with CRWT. n = 10 mice per group, 2 biological repeats. Central tendency: median. Two-sided unpaired T-test. GoF, gram of faeces. D At 30 dpi, blood was taken from mice that cleared infection with CRWT or CRECO25b+pespO. An ELISA was conducted against heat-killed EC958WT (expressing O25b) and an isogenic rough mutant (EC958∆rfb). CRWT infected mice had no detectable IgG responses to EC958WT or EC958∆rfb. CRECO25b+pespO infected mice had IgG responses specifically against EC958WT. n = 10 mice per group, 3 biological repeats. Central tendency: mean. Two-sided unpaired t-tests. ns non-significant; ****, p < 0.0001. Source data and exact p-values are provided in the Source Data file.
