Maziar Divangahi, Principal Investigator, Nargis Khan, Postdoctoral Fellow and first author of the study, Jeff Downey, PhD candidate and co-first author of the study

Cracking the Code of Stem Cells in TB

Congratulations Dr Nargis Khan (PDF) and Jeffrey Downey (PhD trainee), from the Dr. Maziar Divangahi laboratory, on their new study published today in Cell! The study shows that stem cells can be targeted for protective vaccination as well as be hijacked by a pathogen to increase TB virulence.

Dr. Maziar Divangahi’s latest study is in follow up to his previous work that showed that exposure of bone marrow stem cells to a live BCG vaccine (the only available vaccine for TB) reprograms these cells to generate protective innate immunity against TB. However, it was still not know what happened to these stem cells after they were exposed to the pathogen Mycobacterium tuberculosis (Mtb). In this study, the team demonstrates that soon after Mtb infection, the bacteria translocate from the lungs to the bone marrow and reprograms stem cells to impair innate immunity against TB.


“What’s new in this study is that we now know that Mtb hijacks the immune response at the very early phase of infection by accessing the bone marrow and manipulating stem cells. This leads to the generation of impaired innate immune cells, which are effectively incapacitated to fight the infection in the lung, thus allowing the bacteria to grow.”

Dr. Nargis Khan

Once the function of the stem cells has been corrupted by the Mtb pathogen, they lose their ability to fight off the infection in the lungs. In essence, alternative approaches that crack the protective code of stem cells in the bone marrow are urgently needed to eradicate TB.

Read the News Releases:

Read the publication:

Nargis Khan, Jeffrey Downey, Joaquin Sanz, Eva Kaufmann, Birte Blankenhaus, Alain Pacis, Erwan Pernet, Eisha Ahmed, Silvia Cardoso, Anastasia Nijnik, Bruce Mazer, Christopher Sassetti, Marcel A. Behr, Miguel P. Soares, Luis B. Barreiro and Maziar Divangahi. M. tuberculosis reprograms hematopoietic stem cells to limit myelopoiesis and impair trained immunity. Cell. 2020. 183(3): p752-770.E22.