Antibody-Bovine Seminal RNase Fusion Protein

Creative Biolabs is one of the well-recognized experts in offering comprehensive antibody discovery and production services. Based on enriched experience and advanced platforms, we provide professional antibody development and antibody-enzyme fusion expression strategy to promote your project. At present, we offer high-quality antibody-bovine seminal RNase fusion protein service.

Bovine Seminal RNase

Bovine seminal RNase (BSR) is one of the members of the ribonuclease superfamily derived from the seminal fluid within the seminal vesicles of bulls. It is capable of performing a variety of physiological activities, not only the tumoricidal activity. The native state of BSR is an equilibrium mixture of dimers described as ‘swapped’ and ‘unswapped’. The ‘swapped’ dimeric form presents a stable and compact quaternary structure that allows the RNase to evade the RNase inhibitor (possibly by steric hindrance), and thus contribute to the potent antitumor activity of BSR. Endocytosis and intracellular routing mechanisms of the dimer differ from monomeric RNases and may involve selective translocation to the trans-Golgi network in malignant cells, further contributing to the cytotoxicity of BSR. The dimeric nature of BSR has inspired genetic manipulation and structural engineering of monomeric RNases to make them more potent antitumor agents.

Fig.1 Amino acid sequences and three-dimensional structures of RNase A and BS-RNase. (Lee, 2005)

Antibody-Bovine Seminal RNase Fusion Protein

In the light of the anticancer activity of BSR, the fusion of BSR to an antibody reactive with tumor-associated human placental alkaline phosphatase (hPLAP) resulted in cytotoxicity of antigen-positive carcinoma cells in the nanomolar range. Studies have shown that scFv-BSRNase fusion protein increased its anti-tumour activity by over 2 x 10⁴-fold. In addition to the simple scFv-BSRNase fusion protein, the researcher constructed five other derivatives with additional peptides designed to improve folding and intracellular trafficking and delivery. They found that the molecule with most cytotoxic to the antigen (PLAP)-positive cells in vitro is one that contains a C-terminal 'KDEL' endoplasmic reticulum retention signal and a peptide sequence derived from diphtheria toxin.

Fig.2 Schematic diagram illustrating the intended modular domain structure of the constructed immunotoxins, with different permutations of the additional sequences. (Deonarain, 1998)

Creative Biolabs has advanced antibody-enzyme fusion protein platform and experienced scientist team to help clients develop antibody-bovine seminal RNase fusion protein in a timely and cost-effective manner. We also provide other various services regarding antibody-enzyme conjugate development. Please feel free to contact us for more information and a detailed quote.

References

1. Lee, J. E.; Raines, R. T. Cytotoxicity of bovine seminal ribonuclease: monomer versus dimer. Biochemistry. 2005, 44(48), 15760-15767.
2. Deonarain, M. P.; Epenetos, A. A. Design, characterization and anti-tumour cytotoxicity of a panel of recombinant, mammalian ribonuclease-based immunotoxins. British Journal of Cancer. 1998, 77(4), 537-546.