Combined Analysis of IFN-γ, IL-2, IL-5, IL-10, IL-1RA and MCP-1 in QFT Supernatant Is Useful for Distinguishing Active Tuberculosis from Latent Infection

Abstract

The QuantiFERON®-TB Gold In-Tube test (QFT), an interferon-γ release assay, is used to diagnose Mycobacterium tuberculosis, but its inaccuracy in distinguishing active tuberculosis from latent infection is a major concern. There is thus a need for an easy and accurate tool for achieving that goal in daily clinical settings. This study aimed to identify candidate cytokines for specifically differentiating active tuberculosis from latent infection. Our study population consisted of 31 active TB (tuberculosis) patients, 29 LTBI (latent tuberculosis infection) patients and 10 healthy control subjects. We assayed for 27 cytokines in QFT supernatants of both specific antigen-stimulated blood samples (TBAg) and negative-control samples (Nil). We analyzed their specificities and sensitivities by creating receiver operating characteristic (ROC) curves and measuring the area under those curves (AUCs). In TBAg–Nil supernatants, IL-10, IFN-γ, MCP-1 and IL-1RA showed high AUCs of 0.8120, 0.7842, 0.7419 and 0.7375, respectively. Compared with each cytokine alone, combined assay for these top four cytokines showed positive rates in diagnosing active TB, and GDA analysis revealed that MCP-1 and IL-5 are potent in distinguishing active TB from LTBI, with Wilk’s lambda = 0.718 (p < 0.001). Furthermore, utilizing the unique characteristic of IL-2 that its TBAg–Nil supernatant levels are higher in LTBI compared to active TB, the difference between IFN-γ and IL-2 showed a large AUC of 0.8910. In summary, besides IFN-γ, IL-2, IL-5, IL-10, IL-1RA and MCP-1 in QFT supernatants may be useful for distinguishing active TB from LTBI. Those cytokines may also help us understand the difference in pathogenesis between active TB and LTBI.

Evaluation of a whole‐blood chemiluminescent immunoassay of IFN‐γ, IP‐10, and MCP‐1 for diagnosis of active pulmonary tuberculosis and tuberculous pleurisy patients

“…The sensitivity of TB‐specific IFN‐γ (85.8%) was higher than that of TB‐specific IP‐10 (72.4%) (p < 0.001), and this result was consistent with Suzukawa and collaborator's reports , in which the sensitivities of IFN‐γ and IP‐10 were 90.3% and 73.3%, respectively, Suzukawa' study included an LTBI group that is not in our study. The differences between IFN‐γ and IP‐10 responses may be induced by the reasons as follow: (i) IFN‐γ is a cytokine produced by specific T cells stimulated by the antigens from an antigen presenting cell (APC), whereas IP‐10 is produced by APCs in response to signals from a range of cytokines (IL‐1, IL‐2, IFN‐γ, IFN‐a, TNF‐a) together with receptor‐mediated signals from adjacent T cells; (ii) IP‐10 is not directly dependent on IFN‐γ expression, and can be induced by non‐IFN‐γ producing T cell subpopulations, potentially leading to a more T‐cell antigen recognition .…”

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

“…In this pilot study, we detected a number of protein changes in stimulated plasma from QFT-GIT supernatants, including cytokines and chemokines (IL-2, Il-1Ra, IL-10, and IP-10) that have been detected previously ( 15 – 22 ). We were not able to confirm all proteins in LTBI that have been identified ( 18 , 20 ).…”

Gaps in Study Design for Immune Parameter Research for Latent Tuberculosis Infection: A Systematic Review

“…Among the main ones described are IFN-γ, produced by T CD4+, CD8+, and NK cells, and IL-1 and TNF-α, secreted by macrophages and lymphocytes, known to prevent the growth and multiplication of mycobacteria in host cells [6,7]. However, additional biomarkers such as IL-2, IL-5, IL-10, IL-1RA, and MCP have been studied for their ability to differentiate between the LTBI and active TB [8], and it is believed that the cellular and immune profile expressed during tuberculous infection depends to a great extent on the stage of disease, i.e., LTBI or active, where immune biomarkers present in blood could have the ability to differentiate with greater precision between both stages [9].…”