Keratin 5 (KRT5) is a type II intermediate filament protein encoded by the *KRT5* gene, primarily expressed in basal keratinocytes of stratified epithelia, such as skin, breast, and other epithelial tissues. As a key structural component of the cytoskeleton, it pairs with type I keratins (e.g., KRT14) to form networks that maintain cellular integrity, mechanical resilience, and tissue homeostasis. KRT5 is a well-established marker for basal epithelial cells and progenitor cells, playing roles in cell differentiation, wound healing, and stress response.
Antibodies targeting KRT5 are widely used in research and diagnostics. In pathology, KRT5 antibodies help identify basal cell carcinomas, squamous cell carcinomas, and certain subtypes of breast cancer (e.g., basal-like breast cancer). They are also employed to study benign skin disorders, such as epidermolysis bullosa simplex, where *KRT5* mutations disrupt keratin filament assembly. Additionally, these antibodies aid in distinguishing epithelial lineages in developmental biology and cancer research.
Commercially available KRT5 antibodies are validated for techniques like immunohistochemistry (IHC), immunofluorescence (IF), and Western blotting. Their specificity and reliability make them critical tools for characterizing tissue architecture, tumor classification, and understanding epithelial-mesenchymal transitions. Recent studies also explore KRT5's potential as a prognostic indicator or therapeutic target in malignancies, underscoring its biomedical relevance.