Journal: mBio
Article Title: Listeria -Vectored Multiantigenic Tuberculosis Vaccine Enhances Protective Immunity against Aerosol Challenge with Virulent Mycobacterium tuberculosis in BCG-Immunized C57BL/6 and BALB/c Mice
doi: 10.1128/mbio.00687-22
Figure Lengend Snippet: Efficacy against M. tuberculosis aerosol challenge of boosting BCG-primed mice with a combination of recombinant attenuated L. monocytogenes vaccines expressing 5 M. tuberculosis antigens. (a) Efficacy of boosting with 5Ag recombinant attenuated L. monocytogenes vaccines i.m. once versus twice. BALB/c mice ( n = 8/group) were immunized i.d. with PBS or with BCG at week 0. BCG-primed mice were either not boosted or boosted intramuscularly (i.m.) or subcutaneously (s.c.) once (×1) at week 18 with L. monocytogenes vector (LmV) or the combination of rLm4Ag (expressing M. tuberculosis fusion protein Mpt64-TB10.4-ESAT6-CFP10) and rLm30. An additional group was boosted twice (×2) at weeks 14 and 18 with rLm4Ag plus rLm30. The mice were then challenged with aerosolized M. tuberculosis Erdman (average of 19 CFU delivered to the lungs of each animal, as assayed at day 1 postchallenge to 2 mice) at week 22 and euthanized at week 32 (top). Lungs (bottom left) and spleens (bottom right) of mice were assayed for organ bacterial burden. Shown are means ± SEM. One symbol represents one animal. Organ log 10 CFU were analyzed by one-way ANOVA. *, P < 0.05; ****, P < 0.0001 by Tukey’s multiple-comparison test; #, P < 0.05 by Fisher’s LSD test (Prism 9.2.0). (b) Efficacy of 5Ag recombinant attenuated L. monocytogenes vaccines by route of administration. BALB/c mice (8/group) were immunized i.d. with PBS (sham) or 5 × 10 5 CFU BCG at week 0. Mice immunized i.d. with BCG were either not boosted or boosted i.m., i.d., subcutaneously (s.c.), or intravenously (i.v.) once at week 18 with 2 × 10 6 CFU of the combination of rLm4Ag (expressing Mpt64-TB10.4-ESAT6-CFP10) and rLm30. The mice were then challenged at week 22 with aerosolized M. tuberculosis Erdman at the same time as the companion experiment shown in panel a (average of 19 CFU delivered to the lungs of each animal) and euthanized at week 26 (top). Afterward, lungs (bottom left) and spleens (bottom right) were removed and assayed for bacillus burdens. Shown are means ± SEM. Each symbol represents one mouse. *, P < 0.05; ***, P < 0.001; ****, P < 0.0001 by one-way ANOVA with Fisher’s LSD test (Prism 9.2.0).
Article Snippet: M. tuberculosis Erdman strain (ATCC 35801) was harvested from infected outbred guinea pigs to verify virulence, cultured on 7H11 agar, subjected to gentle sonication to obtain a single-cell suspension, and frozen at −80°C for use in animal challenge experiments.
Techniques: Aerosol, Recombinant, Vaccines, Expressing, Plasmid Preparation, Comparison