Post-translational modification profile of recombinant factor VII produced in human cell lines

• Grant number: 16/23545-0
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): April 01, 2017
• Effective date (End): September 30, 2017
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Dimas Tadeu Covas
• Grantee: Marcela Cristina Corrêa de Freitas
• Supervisor: Michael Butler
• Host Institution: Hemocentro de Ribeirão Preto. Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da USP (HCMRP). Secretaria da Saúde (São Paulo - Estado). Ribeirão Preto , SP, Brazil
• Research place: National Institute for Bioprocessing Research and Training (NIBRT), Ireland
• Associated to the scholarship: 15/19017-6 - Plataform for recombinant factor VII production in human cells: development of a high eficient and stable national biopharmaceutical., BP.PD

Abstract

Inhibitory antibodies development is currently the most significant treatment complication seen in patients with hemophilia and is associated with considerable morbidity and decreased life quality. Approximately 5% of patients with hemophilia B and 20 to 30% of patients with severe hemophilia A, who use factor IX (FIX) and factor VIII (FVIII) replacement therapy, respectively, develop antibodies that inhibit the activity of the infused factor. It is known that the development of inhibitory antibodies by hemophiliac patients is closely related with immunogenic epitopes present in these proteins. These coagulation factors are produced in hamsters cells which insert a different post-translational modification profile when compared with the human profile. Patients with high-titer/high-responding inhibitors must be treated with bypassing agents that can achieve hemostasis. Over the years, many studies have identified activated factor VII (FVIIa) as an attractive candidate for hemostasis, independent of FVIII/FIX, making this coagulation factor an alternative for hemophilia patients with inhibitory antibodies. However recombinant factor VII is produced in BHK-21 cells (Baby hamster kidney cells) and as well as the others coagulation factors, it may contain immunogenic epitopes. In this context, becomes extremely important to produce recombinant proteins with complex post-translational modifications in a cell line not yet used. At the Blood Center of Ribeirão Preto we have been using the Sk-Hep-1 and HKB-11 human cell lines for the production of recombinant FVII with promising results. However, it is not enough to have a great production if our rFVII is not safer and more effective than those on the market. Therefore determining the profile of post-translational modifications is crucial to continue this work, which aims to offer a better medicine that may in the future improve the patient's life quality. (AU)