Host response to Mycobacterial cell wall subunit during experimental tuberculosis in mice

The cell-wall protein-peptidoglycan complex (CW-PPC) of Mycobacterium tuberculosis, an immunologically potent component, was used to study the correlation between immune response and in vivo bacterial multiplication in the course of experimental tuberculosis infection in mice. Antibodies to CW-PPC were detected only after seven weeks of infection with M. tuberculosis H37Rv and afterwards no significant change was seen throughout the experiment. Delayed type hypersensitivity (DTH) to CW-PPC showed a gradual increase from the fifth week onward with a maximum during the 12th week after infection (p.in.) which did not change significantly afterward. The increased immune response in the course of infection correlated well with the multiplication rate of bacilli in the lungs. These results indicate a role of CW-PPC in antituberculous immunity.