UCLA-led study has identified a protein that appears to play a key role in protecting people infected with Mycobacterium tuberculosis—the bacterium that causes tuberculosis—from developing the active form of the disease. The protein, interleukin-32, was discovered to be one biomarker of adequate host defense against TB.

The discovery could help doctors identify people who are at the greatest risk for the highly contagious and potentially fatal lung disease, and it could point the way toward new treatment strategies for TB.

The study, conducted in partnership with researchers from Harvard University School of Public Health and the University of Michigan School of Medicine, was published in the Aug. 20 online edition of the journal Science Translational Medicine.

The findings underscore the importance of maintaining sufficient levels of vitamin D to effectively combat the pathogen that causes TB. The researchers found that the protective protein, interleukin-32, can induce the killing of the TB bacterium only in the presence of sufficient levels of vitamin D.