SEMA3G (Semaphorin-3G) is a secreted protein belonging to the semaphorin family, which regulates diverse biological processes, including neural development, angiogenesis, and immune modulation. As a class 3 semaphorin, SEMA3G functions as a guidance cue by binding to receptors such as plexins and neuropilins, activating downstream signaling pathways (e.g., Rho GTPases) to influence cell migration, adhesion, and proliferation. SEMA3G antibodies are immunological tools designed to detect and study this protein’s expression, localization, and functional roles. These antibodies are typically developed in host species (e.g., rabbit or mouse) using immunogenic peptide regions of SEMA3G, and they vary in clonality (monoclonal/polyoclonal) and applications (Western blot, immunohistochemistry, immunofluorescence). Research highlights SEMA3G’s involvement in tumor suppression, particularly in gliomas and breast cancer, where it may inhibit angiogenesis by downregulating VEGF or modulating immune cell infiltration. Its dysregulation has also been linked to metabolic disorders and neurodegenerative conditions. Validated SEMA3G antibodies are critical for elucidating its tissue-specific functions and therapeutic potential, though specificity and cross-reactivity challenges require rigorous validation using knockout controls. Current studies focus on its dual roles in cancer progression and neuronal repair, making it a target for biomarker discovery and precision medicine.