IFI30 (Interferon Gamma-Inducible Protein 30) is a lysosomal thiol reductase that catalyzes the reduction of protein disulfide bonds 1. Its primary function involves antigen processing and presentation, where it reduces disulfide bonds of endocytosed proteins to facilitate their unfolding and degradation for both MHC class I and class II-restricted antigen presentation 1. IFI30 employs a thioredoxin-like mechanism using an N-terminal CXXC active site motif, with lysosomal cysteine serving as the physiological reducing agent to regenerate active enzyme. Beyond immune functions, IFI30 has emerged as a significant player in cancer progression. In esophageal squamous cell carcinoma, IFI30 knockdown inhibits proliferation, migration, and invasion while promoting apoptosis and senescence through JNK pathway activation and P21/P16 upregulation 2. Similarly, in glioblastoma, high IFI30 expression correlates with poor prognosis and an immunosuppressive microenvironment characterized by increased regulatory T cells and M0 macrophages 3. IFI30 has also been implicated in nonalcoholic fatty liver disease susceptibility 4 and atherosclerotic plaque instability where elevated expression associates with enhanced inflammation 5. Additionally, IFI30 is upregulated in severe COVID-19 patients 6 and is required for vascular development during angiogenesis 7, suggesting multifaceted roles beyond classical antigen processing.