Highly Multiplexed Proteomic Analysis of Quantiferon Supernatants To Identify Biomarkers of Latent Tuberculosis Infection

• Published in: Journal of clinical microbiology Vol. 55; no. 2; pp. 391 - 402
• Main Authors: De Groote, Mary Ann, Higgins, Michael, Hraha, Thomas, Wall, Kirsten, Wilson, Michael L., Sterling, David G., Janjic, Nebojsa, Reves, Randall, Ochsner, Urs A., Belknap, Robert
• Format: Journal Article
• Language: English
• Published: United States American Society for Microbiology 01.02.2017
• Subjects: Adolescent; Adult; Biomarkers - analysis; Emigrants and Immigrants; Enzyme-Linked Immunospot Assay - methods; Female; Humans; Immunologic Factors - analysis; Interferon-gamma Release Tests - methods; Latent Tuberculosis - diagnosis; Male; Middle Aged; Mycobacteriology and Aerobic Actinomycetes; Mycobacterium; Proteome - analysis; Proteomics - methods; Tuberculin Test - methods; United States; Young Adult; diagnosis; immunity; proteomics; latent infection; biomarkers; tuberculosis
• ISSN: 0095-1137; 1098-660X
• DOI: 10.1128/JCM.01646-16

The tests for diagnosing latent tuberculosis infection (LTBI) are limited by a poor predictive value for identifying people at the highest risk for progressing to active tuberculosis (TB) and have various sensitivities and specificities in different populations. Identifying a more robust signature for LTBI is important for TB prevention and elimination. A pilot study was conducted with samples from immigrants to the United States that were screened for LTBI by the three commercially approved tests, namely, the tuberculin skin test (TST), the Quantiferon-TB Gold in-tube (QFT-GIT), and the T-SPOT.TB (T-SPOT). QFT-GIT supernatants from 13 people with concordant positive results and 26 people with concordant negative results were analyzed via the highly multiplexed SOMAscan proteomic assay. The proteins in the stimulated supernatants that distinguished LTBI from controls included interleukin-2 (IL-2), monocyte chemotactic protein 2 (MCP-2), interferon gamma inducible protein-10 (IP-10), interferon gamma (IFN-γ), tumor necrosis factor superfamily member 14 (TNFSF14, also known as LIGHT), monokine induced by gamma interferon (MIG), and granzyme B ( P <0.00001). In addition, antigen stimulation increased the expression of heparin-binding EGF-like growth factor (HB-EGF) and activin AB in LTBI samples. In nil tubes, LIGHT was the most significant marker ( P <0.0001) and was elevated in LTBI subjects. Other prominent markers in nonstimulated QFT-GIT supernatants were the complement-3 components C3b, iC3b, and C3d, which were upregulated in LTBI and markedly decreased upon stimulation. We found known and novel proteins that warrant further studies for developing improved tests for LTBI, for predicting progression to active disease, and for discriminating LTBI from active TB.