Mycobacterium tuberculosis -- the bacterium that causes most cases of tuberculosis -- spreads infection by blocking a naturally triggered immune response that would cause the infected cells to die. The research, published online this week in Nature Immunology, provides possible new avenues for designing inhibiting drugs to prevent mycobacterial diseases.
Mycobacteria tuberculosis infects immune cells called macrophages, which function as temporary 'incubators' while the bacteria multiply. Eventually the macrophages burst, releasing the bacteria to infect other cells. Normally macrophages infected with bacteria would undergo a form of cell death called apoptosis and trigger an immune response.
Heinz Remold and colleagues found that M. tuberculosis prevent macrophages from undergoing apoptosis. Instead, M. tuberculosis caused macrophages to die by necrosis, another form of cell death that allows the bacteria to escape from their host cells and infect new cells. By revealing how M. tuberculosis can evade the immune system this study provides significant insight into the development of tuberculosis disease.
Heinz G. Remold (Brigham and Women's Hospital Medicine, Boston, MA, USA)
Abstract available online.
(C) Nature Immunology press release.
Message posted by: Trevor M. D'Souza