Cytokines

Key Biological Properties: Uteroglobin is a steroid-inducible protein with anti-inflammatory and immunomodulatory properties . It inhibits soluble phospholipase A2 activity and binds hydrophobic ligands such as progesterone, retinols, and phospholipids .

Expression Patterns: Uteroglobin is expressed in the mucosal epithelia of organs that communicate with the external environment, such as the lungs, uterus, and gastrointestinal tract . It is also present in the blood, urine, and other body fluids .

Tissue Distribution: The protein is specifically expressed in club cells in the lungs and is also found in the endometrium, tracheo-bronchial, gastrointestinal, prostatic, and seminal vesicular epithelium .

Primary Biological Functions: Uteroglobin plays a crucial role in modulating immune responses and has anti-inflammatory, antichemotactic, antiallergic, antitumorigenic, and embryonic growth-stimulatory activities . It inhibits platelet aggregation and the migration and invasion of normal and cancer cells .

Role in Immune Responses: Uteroglobin’s immunomodulatory functions include inhibiting the production of pro-inflammatory cytokines and regulating the stability of mRNA . It also has a tolerogenic effect on blastomeres and spermatozoa, protecting them from recognition by maternal lymphocytes .

Pathogen Recognition: Uteroglobin binds and sequesters pro-inflammatory lipid mediators, thereby reducing inflammation and aiding in pathogen recognition .

Mechanisms with Other Molecules and Cells: Uteroglobin interacts with various molecules, including phospholipids and polychlorinated biphenyls, and inhibits phospholipase A2 activity . It also functions via a putative receptor-mediated pathway that is not yet fully defined .

Binding Partners: The protein binds to hydrophobic ligands such as progesterone, retinols, and phospholipids . It also interacts with receptors on the surface of cells, initiating downstream signaling cascades .

Downstream Signaling Cascades: Uteroglobin’s interaction with its receptors triggers signaling pathways that regulate immune responses and inflammation .

Expression and Activity Control: The expression of uteroglobin is regulated by steroid hormones, particularly progesterone . In the respiratory tract, its synthesis is controlled by glucocorticoids .

Transcriptional Regulation: The SCGB1A1 gene is regulated by ovarian steroids, with progesterone playing a significant role in its expression in the endometrium . Nonsteroid hormones like prolactin also augment its expression .

Post-Translational Modifications: Uteroglobin undergoes post-translational modifications, including disulfide bond formation, which is crucial for its dimeric structure and function .

Biomedical Research: Uteroglobin is studied for its anti-inflammatory and immunomodulatory properties, making it a potential target for drug development .

Diagnostic Tools: Antibodies against uteroglobin are used in various diagnostic applications, including Western Blot, Immunohistochemistry, ELISA, and Flow Cytometry .

Therapeutic Strategies: Due to its anti-inflammatory and antiallergic properties, uteroglobin is being explored as a therapeutic agent for treating inflammatory and autoimmune diseases .

Development to Aging and Disease: Uteroglobin plays a critical role throughout the life cycle, from embryonic development to aging . Its expression is crucial during early pregnancy for embryo implantation and growth . In aging, its anti-inflammatory properties help mitigate oxidative damage and inflammation .