Invertigation of a mouse - human chimeric monoclonal antibody to CD 20 (ANTI-CD 20 mAb)

Abstract

In last three decades, anti-CD20 monoclonal antibody (anti-CD20 mAb) has justified the main treatment for many B-cell disorders such as B-cell lymphoma, B-cel chronic lymphocytic leukemia (B-CLL), etc. Rituximab, a monoclonal chimeric antibody targeting the CD20 antigen expressed on B cells, has been used extensively in the treatment of B cell malignancies; however, the medical expense for Rituximab treatment, is still the biggest difficulty for the patients, particularly for Vietnamese patients. Therefore, we aimed to develop a bio-similar drug of Rituximab to reduce the cost of treatment based on the anti-CD20 mAb heavy chain and light chain gene sequences in the copyright US 7381560 B2, which will be expired soon. From our preliminary data, we have succeeded in creating CD20-expressing CHO-DG44 cells, and confirmed that these cells can secrete the target anti-CD20 antibody. This works try to screening and isolating the best cell line for producing anti-CD20 mAb from CHO-DG44 transfectant as part of Rituximab bio-similar project. Three single clones 6G8, 2C10 and 5D2 were chosen to scale up and purify for further bioactivity analysis. Finally, I found that 6G8 is the best cell line for producing the anti-CD20 mAb among 150 checked cell lines. This study presented the important part (6G8 cell line) in Rituximab bio-similar project, which potentially reduces the Rituximab treatment cost for patients in Vietnam. Key words: anti-CD20 mAb, CHO-DG44, Rituximab, monoclonal antibody.