The increasing global incidence of non-tuberculous mycobacterial (NTM) infection is of growing concern. New evidence of person-to-person transmission of multidrug-resistant NTM adds to the global concern. The reasons why certain individuals are at risk of these infections is unknown. Using high definition flow cytometry we studied the immune profiles of NTM patients and matched healthy controls to identify immune signatures associated with NTM infection. In NTM patients, we found elevated T cell activation and exhaustion markers and increased frequency of regulatory T cells. We also observed significantly lower numbers of polyfunctional T cells, suggesting compromised T cell ‘quality’ in individuals susceptible to NTM infection. This unique immune signature associated with NTM infection was confirmed in two different cohorts of susceptible patients. Collectively, these data could be of significant diagnostic and prognostic value for patient management and could be used to identify new therapeutic pathways and new targets for immunomodulation.

This manuscript under review.

Collaborators: Dr Michael Trotter, Dr Andrew Burke, Dr Rachel Thomson in conjunction with the NTM-net.