Abstract

IFNGR1 and STAT1 are key components of the JAK–STAT pathway mediated by IFN-γ, with potential as important biomarkers for TB. INFGR1 acts as the binding and signal reception site for IFN-γ. STAT1, on the other hand, acts as a transcription factor that transmits the IFN-γ signal to the nucleus. Their expression has been rarely studied in pulmonary tuberculosis (TB). This cross-sectional study aimed to evaluate IFNGR1 and STAT1 expression in pulmonary TB patients (PTB) and their household contacts (HC), including latent tuberculosis infection (LTBI) and healthy household contacts (HS) in Indonesia. This study included 43 newly diagnosed PTB and 66 HC (38 LTBI and 28 HS). IFNGR1 and STAT1 expression were measured through real-time qPCR, and multivariate logistic regression was used to further evaluate their correlation with active and latent TB. We also evaluated IFNGR1 and STAT1 expression with TB severity and their diagnostic performance. IFNGR1 expression was significantly downregulated in PTB compared to LTBI (ρ = 0.0012) and HS (ρ = 0.0110). STAT1 expression in PTB was upregulated compared to LTBI and HS, but the differences were not statistically significant (ρ = 0.5794 and ρ = 0.9135). Higher IFNGR1 expression was correlated with a decreased risk of PTB. STAT1 expression was correlated with PTB, but the result did not reach statistical significance. Receiver operating characteristic (ROC) curve analysis showed that IFNGR1 expression can significantly differentiate PTB from HS and PTB from LTBI. In contrast, STAT1 expression became significant when combined with clinical factors. Our study suggests that IFNGR1 expression has potential as a biomarker for early TB detection, while STAT1 also shows potential, but should be interpreted with clinical factors.

Key words: STAT1, IFNGR1, Pulmonary tuberculosis, Latent tuberculosis