Cathepsin D is a lysosomal aspartic protease belonging to the peptidase A1 family, primarily involved in protein degradation, antigen processing, and apoptosis regulation. It is synthesized as an inactive precursor (pro-cathepsin D) and undergoes proteolytic maturation in acidic lysosomal environments. Dysregulation of Cathepsin D has been implicated in various pathologies, including cancer metastasis, neurodegenerative disorders (e.g., Alzheimer’s disease via amyloid-beta plaque formation), and inflammatory conditions. Its overexpression in tumors correlates with poor prognosis, making it a potential biomarker and therapeutic target.
Antibodies targeting Cathepsin D are essential tools for studying its expression, localization, and function. These antibodies enable detection through techniques like Western blotting, immunohistochemistry (IHC), and immunofluorescence (IF). Specific epitopes recognized by these antibodies may vary, with some targeting the pro-form, mature enzyme, or specific cleavage sites. Validation in relevant cell lines or tissues is critical to ensure specificity, given structural similarities among aspartic proteases. Research applications include investigating lysosomal dysfunction, autophagy mechanisms, and disease progression. Commercial Cathepsin D antibodies are typically raised in rabbits or mice, with clones validated for cross-reactivity in human, mouse, and rat models. Recent studies also explore its role in extracellular matrix remodeling and immune modulation, expanding its relevance in translational research.