ISSN: 0974-276X
Jie Cheng, Quxiao Du, Xiaoli Zhang, Yafeng Ren, Boai Zhang and Xiaodong Feng
Background: This study aimed to find the linker length with minimal impact among chains to fight against the structure and function of cervical cancer single-chain antibody.
Methods: The original variable region of heavy chain (VH) and variable region of light chain (VL), and the singlechain antibody with (Gly4Ser)n linkers of different lengths (n=1~8) were modeled using SWISS-MODEL homologous modeling. Comparison of the similarity of original VH/VL and VHn/VLn was carried out by applying the algorithm of spatial hierarchical alignment based on the spherical coordinates. The fore and aft distance and diffusion radius of α were also calculated. The stability of antibody with different linker length was then compared. ELISA method was adopted to evaluate the immunological activity of single-chain antibody with different linkers. MTT assay was used to analyze the inhibition effect of ScFv-n on cervical cancer cells.
Results: When linker unit n=4, the structures were the most similar between ScFv and the original VH/VL. When n=3, the similarity of it had little differences to that when n=4, and the influence of adding connecting peptide on the stability of single-chain antibody was the least, when n=3. The result of ELISA and MTT methods indicated that when n=3, single-chain antibody gained the highest activity.
Conclusion: The optimum length of linker of anti-human cervical cancer single-chain antibody was n=3 from the point of mathematical modeling and biology experiments. This study provided new ideas for the design and constructions of single-chain antibody, and theoretical basis for the treatment of cervical cancer.