ANKRD22 as a novel diagnostic biomarker and immunomodulator in tuberculosis disease: A multi-cohort and clinical validation study

BACKGROUND: Tuberculosis (TB) remains a major global health threat. ANKRD22 has emerged as a candidate biomarker from transcriptomic studies, but its diagnostic and functional role in TB is unclear. METHODS: We analyzed 23 public transcriptomic datasets and validated results in a clinical cohort. ANKRD22 expression was measured by RT‑qPCR. Diagnostic performance was evaluated using ROC analysis. Immune correlations were investigated via GO, KEGG, GSEA, and immune deconvolution. In vitro studies used H37Ra‑infected THP‑1 macrophages with ANKRD22 knockdown. RESULTS: ANKRD22 expression was significantly upregulated in TB disease compared to infected individuals and healthy controls, increased progressively along the disease continuum, and declined following effective anti‑TB treatment. It demonstrated strong diagnostic performance across multiple datasets (AUC range: 0.709-0.986) and in clinical samples (AUC = 0.855). High ANKRD22 expression was positively correlated with MLR and associated with an immunosuppressive microenvironment characterized by increased infiltration of neutrophils, mast cells, regulatory T cells, and myeloid‑derived suppressor cells, alongside decreased NK cells. In vitro, ANKRD22 knockdown attenuated M2 macrophage polarization. CONCLUSION: ANKRD22 is a promising diagnostic biomarker for active TB and is linked to an immunosuppressive immune microenvironment, supporting its potential for diagnosis and host‑directed therapy.