Recombinant Human THB protein

THB (Trichosanthin-Human serum albumin-Biotin) recombinant protein is a multifunctional fusion protein engineered for targeted therapeutic applications. Trichosanthin (TCS), a ribosome-inactivating protein derived from the root tuber of *Trichosanthes kirilowii*, has historically been studied for its abortifacient and antiviral properties. However, its clinical use has been limited by nonspecific cytotoxicity and immunogenicity. To address these challenges, researchers developed THB by genetically fusing TCS with human serum albumin (HSA) and biotinylation motifs. HSA enhances pharmacokinetics by prolonging circulatory half-life and reducing renal clearance, while biotin enables site-specific conjugation with targeting ligands (e.g., antibodies) via streptavidin-biotin interactions.

This modular design allows THB to combine the cytotoxic potential of TCS with precision targeting, minimizing off-target effects. The recombinant protein is typically produced in *E. coli* or yeast expression systems, followed by purification and biotinylation processes. Preclinical studies highlight its potential in cancer therapy, particularly for tumors overexpressing biotin receptors, such as breast and lung cancers. Additionally, THB’s adaptability supports its exploration in drug delivery, diagnostics, and immunoconjugate therapies. Challenges remain in optimizing production yield, stability, and immunocompatibility, but its engineered structure exemplifies advancements in protein engineering for targeted biomedical interventions. Current research focuses on improving tumor penetration and evaluating long-term safety profiles for translational applications.