title: [Study on the construction and expression of the human 4-1BBL extracellular domain/anti-CD20 Fab' fusion protein].
abstract: Several studies have demonstrated the role of 4-1BBL in T cell activation. Furthermore, enhanced 4-1BB/4-1BBL interaction has been shown to amplify T-cell-mediated antitumor immunity in several mouse models. However, when applied in humans, it was difficult to generate sufficient T cells ex vivo and whole cell vaccines to transfer back into patients. To overcome this difficulty, we have focused on producing the human 4-1BBL extracellular domain/anti-CD20 Fab' fusion protein. In this report, PCR and overlap PCR were used to construct the human 4-1BBL extracellular domain/anti-CD20 Fab' expression vector. DNA sequence was analyzed by the Terminus of Dideoxy Nucleotide. The product was purified by affinity chromatography and analyzed by SDS-PAGE and HPLC; its antigen binding activity was examined by rosetting assay. The data of DNA sequence showed that the human 4-1BBL extracellular domain/anti-CD20 Fab' fusion protein was corrected. The fusion protein was recovered in high yield (up to 200 microg/mL) after E-taq purification. The fusion protein was capable of simultaneous binding to stimulated Jurkat cells and Raji cells as shown by cellular rosetting. In conclusion, the human 4-1BBL extracellular domain/anti-CD20 Fab' fusion protein was induced to express in E. coli 16C9. The results of some biological activity experiments indicated that the fusion protein could bind to stimulated Jurkat cells and Raji cells. Furthermore, 4-1BBL-negative tumors can be converted into 4-1BBL-positive tumors by the fusion protein without the need for 4-1BBL gene transfer to the malignant cells.
authors.affiliation: Binzhou Medical College, Binzhou 256603, China. jiangwg@gmail.com
authors.forename: Wenguo
authors.initials: W
authors.lastname: Jiang
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Xiong
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Hongxing
authors.initials: H
authors.lastname: Guo
authors.forename: Ye
authors.initials: Y
authors.lastname: Su
authors.forename: Jingli
authors.initials: J
authors.lastname: Lü
authors.forename: Chunzheng
authors.initials: C
authors.lastname: Yang
mesh_terms: D053330:4-1BB Ligand / Q000096:biosynthesis* / Q000235:genetics; D018033:Antibodies, Bispecific / Q000276:immunology; D018951:Antigens, CD20 / Q000276:immunology*; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000096:biosynthesis* / Q000235:genetics; D007167:Immunotherapy / Q000379:methods; D008228:Lymphoma, Non-Hodgkin / Q000628:therapy; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*
chemical_list: D053330:4-1BB Ligand; D018033:Antibodies, Bispecific; D018951:Antigens, CD20; D007140:Immunoglobulin Fab Fragments; D011993:Recombinant Fusion Proteins