Effective, nonsensitizing vaccination with culture filtrate proteins against virulent Mycobacterium bovis infections in mice

Abstract

Vaccination of mice with Mycobacterium bovis culture filtrate proteins (CFP), prepared in a variety of adjuvants (aluminum hydroxide, Quil-A, and dimethyldioctyldecyl ammonium bromide [DDA]), provided significant protection against an aerosol challenge of virulent M. bovis. Additionally, vaccination with CFP in DDA or Quil-A did not sensitize mice to M. bovis purified protein derivative.

FIG. 1

Course of an aerosol infection with M. bovis 86-579 in mice. Data points show the mean numbers of viable bacteria recovered from the lungs (n = 5 mice/time point) at the indicated time points. Error bars represent standard errors of the means.

FIG. 2

DTH responses in mice following vaccination with subunit vaccines or M. bovis BCG Pasteur. Mice were given two subcutaneous injections of each subunit vaccine or PBS 60 and 30 days prior to infection. Mice vaccinated with M. bovis BCG Pasteur were given one intradermal injection of 10⁶ bacteria 30 days following the last vaccination. Mice (n = 5/group) were injected with M. bovis PPD in the right footpad (10 μg/50 μl). BSA (10 μg/μl), the negative control, was injected into the contralateral footpad 3 days prior to infection. The difference in footpad thickness between BSA- and PPD-injected footpads was measured 48 h after injection (1 day prior to infection). Analysis of variance and Tukey-Kramer’s comparisons of means were used to compare sizes of indurations among mice receiving vaccines and those receiving saline. Error bars represent standard errors of the means. ∗, P < 0.05; †, P > 0.05.