Electric Pulses-mediated Intramuscular Transfection And Expression Of Therapeutic Antibodies

Antibody-based therapeutic proteins achieve their clinical efficacy by inhibition of cell signaling,antibody-dependent cellular cytotoxicity,complement-dependent cytotoxicity with high specificity and efficacy.But immunogenicity and high-cost are two major drawbacks of antibody products.And electroporation(EP),which is a method use series of square wave electric pulses to transfer DNA molecules into stable,nondifferentiated cells efficiently without viral vectors.In this study,we proposed a method that expressing monoclonal antibodies by in vivo electroporation(EP),using mAb 5A8 as model antibody.In the study of in vitro expression,equivalent amount of plasmid pVAX1-5A8-H and pVAX1-5A8-L were co-transfected into HEK293 T cells.Expression and secretion of mAb 5A8 were detected,and mAb 5A8 purified from HEK293 T cell culture supernatant has good affinity to recombinant human CD4.In the study of in vivo expression,DNA plasmids encoding Luciferase reporter gene and Ovalbumin were transferred in to mice skeletal muscle by EP,for selection of EP parameters which provided high expression efficiency and induced low immunogenicity.Then,DNA plasmids respectively encoding light and heavy chain of mAb 5A8 were transferred in to skeletal muscle of mice by EP.In vivo expression of mAb 5A8 lasted for more than 90 days and serum concentration levels of mAb 5A8 could be kept by repeatedly treatments of DNA+EP.Furthermore,different doses of 5A8 encoding plasmid were applied to mice,serum concentration of mAb 5A8 showed high correlation to DNA dosage.We also analyzed the immunogenicity generated from DNA+EP,and results shown no immune responses.Based on these observations,we considered that electroporation was an effective way to express therapeutic antibodies in vivo for long-time treatment in spite of immunogenicity and high-cost.