Identification of ROS-Related Gene TNFSF13B as a Diagnostic Biomarker in Tuberculosis: Insights from WGCNA

Despite medical advances, active tuberculosis (TB) remains difficult to diagnose, particularly in asymptomatic or paucibacillary cases lacking detectable pathogen evidence. Elevated oxidative stress is a hallmark of Mycobacterium tuberculosis (Mtb) infection, and the genes driving this process represent promising diagnostic biomarkers. Transcriptomic profiling captures dynamic host immune responses preceding clinical manifestations, while weighted gene co-expression network analysis (WGCNA) identifies functionally coherent gene modules. Integrating WGCNA with immune infiltration analysis, this study aimed to discover oxidative stress-related hub genes as robust biomarkers to address critical gaps in active TB detection and differential diagnosis.

Microarray data were derived from 10 healthy donors (HCs) and 10 active TB patients recruited from Beijing Chest Hospital. Other external datasets for validation were obtained from the Gene Expression Omnibus database. Correlation analysis of gene expression and immune cell infiltration using the CIBERSORT approach. WGCNA was employed to identify the critical modules associated with immune cells.

WGCNA and immune infiltration analysis identified a monocyte-associated module harboring five ROS-related genes. Among these, TNFSF13B exhibited strong diagnostic performance (AUC > 0.8), served as a key oxidative stress gene in TB macrophages, was tied to energy metabolism. Notably, TNFSF13B expression effectively distinguished TB patients from those with other pulmonary diseases (AUC = 0.892), addressing a critical diagnostic gap, and significantly decreased following anti-tuberculosis therapy (p = 0.0001), suggesting utility in treatment monitoring. These findings were further supported by in vitro data showing markedly elevated TNFSF13B in Mtb-infected THP-1 cells compared to uninfected controls (FC = 5.98, p < 0.001).

Our findings identify TNFSF13B as a macrophage-specific, oxidative stress-related biomarker with strong potential for active TB diagnosis, not only for differential diagnosis from other pulmonary diseases but also for monitoring TB treatment response.