Body's response to different types of TB may affect transmission

According to the World Health Organization, the findings, published in the journal Nature Communications, may help break the cycle of rapid TB transmission

"These findings suggest that strain differences have important implications for how alveolar macrophages respond and how TB manifests and spreads in the body," said study author Padmini Salgame, associate director of the Institute for Public Health at Rutgers University New Jersey School of Medicine.

To better understand transmission and its relationship to treatment outcomes, the team of scientists focused on the effects of these two strains of M.

In a collaborative study with researchers from Rutgers University and Brazil's Núcleo de Doenças Infecciosas (NDI), the strains were identified, comparing "high transmission" and "low transmission" in households of TB patients.

In mice infected with the highly transmissible strain, their lungs rapidly developed clumps of immune cells called granulomas that surrounded the invading bacteria and prevented the development of more severe disease

"By inducing granulomas, potentially developing into cavitary lesions that help the bacteria escape into the airways, the highly transmissible strains of Mycobacterium tuberculosis are more transmissible," said Salgame, who is also a professor in the Department of Medicine

In mice infected with the low-transmitting strain, the invading bacteria were slow to activate alveolar macrophages, which eventually created plaques of inflammation in the lungs that prevented the bacteria from escaping to the airways, and caused them to clump together, Salgame said.

The discovery of the different trajectories taken by these strains offers hope for new ways to stop transmission and treat them

"We've known for a long time that some people with TB are more contagious than others," Salgame said

Other Rutgers authors include Arianne Lovey, Sheetal Verma, Vaishnavi Kaipilyawar and Jerrold Ellner, all at the Center for Emerging Pathogens, and Seema Husain at the Genome Center

Journal Reference :

1. Arianne Lovey, Sheetal Verma, Vaishnavi Kaipilyawar, Rodrigo Ribeiro-Rodrigues, Seema Husain, Moises Palaci, Reynaldo Dietze, Shuyi Ma, Robert D.