Enhanced gamma interferon responses of mouse spleen cells following immunotherapy for tuberculosis relapse

Abstract

Gamma interferon responses of spleen cells in mice were examined during postchemotherapy relapse of intraperitoneally induced latent tuberculous infection. The mycobacterial extract RUTI, which prevented the relapse, significantly enhanced the immune responses to secreted and structural recombinant mycobacterial antigens, suggesting that RUTI-mediated protection was mediated by activated T cells.

Figures

FIG. 1.

Bacillary loads in the spleens of IP-infected mice. Chemotherapy treatment was administered once a week from weeks 3 to 9, and the RUTI vaccine was subcutaneously injected at weeks 9 and 11 (arrows). Black, white, and gray bars refer to control, chemotherapy-treated, and chemotherapy-plus-RUTI-treated groups, respectively. Error bars show standard deviations. Significant differences (P < 0.05) are marked as follows: *, control group; #, chemotherapy-treated group. INH, isoniazid.

FIG. 2.

Enhanced IFN-γ response of C57BL/6 mouse splenocytes against M. tuberculosis antigens following RUTI vaccination. Mean values and standard deviations of results of ELISPOT (A) and ELISA of culture supernatants (B) following the stimulation of spleen cells with different stimuli are shown. The week at which each assay was performed is shown at the right; the antigens used are listed below the graphs. Significant differences (P < 0.05) are marked with asterisks. Black and gray asterisks refer to control and chemotherapy-treated groups, respectively. N.A., not assayed.