TSC22D3 (TSC22 domain family member 3) is a glucocorticoid-inducible transcription factor that serves as a key mediator of glucocorticoid signaling and stress responses. The protein functions primarily as a negative regulator of immune responses and cellular activation pathways 1. Upon glucocorticoid stimulation, TSC22D3 expression is rapidly upregulated and acts to suppress type I interferon responses in dendritic cells and inhibit IFN-γ+ T cell activation, thereby compromising antitumor immunity 1. The protein operates through direct protein-protein interactions, binding to transcription factors like HIF-1α to promote their degradation via the ubiquitin-proteasome pathway 2. In immune regulation, TSC22D3 deficiency enhances NK cell effector function and shifts immune responses from CD4+ to CD8+ T cell-mediated responses, contributing to drug hypersensitivity reactions 3. Beyond immune function, TSC22D3 is involved in osmotic stress responses through activation of JNK signaling pathways and regulation of ion transporters 4. Clinically, TSC22D3 represents a critical node in glucocorticoid therapy efficacy, with its upregulation being essential for anti-inflammatory effects in conditions like asthma 5 and diabetic retinopathy 2, while also potentially contributing to glucocorticoid-induced osteoporosis 6.