title: [Preparation and bioactivity evaluation of streptavidin-tagged human interferon- inducible T cell alpha chemoattractant bifunctional fusion protein].
abstract: OBJECTIVE
  To prepare streptavidin-tagged human interferon-inducible T cell alpha chemoattractant bifunctional fusion proteins (SA/hI-TAC) and evaluate its biological activity.
  
  
  METHODS
  pET24a-SA-hI-TAC/pET21a-hI-TAC-SA plasmids were constructed and expressed in BL21. SA-hI-TAC and hI-TAC-SA fusion proteins were purified by Ni-NTA affinity chromatography, refolded by dialysis and identified by Western blotting. The bifunctionality of the fusion proteins (biotin-binding function and hI-TAC activity) was analyzed by flow cytometry and lymphocyte chemotaxis experiment, respectively.
  
  
  RESULTS
  SA-hI-TAC/hI-TAC-SA fusion proteins were expressed at about 12% and 25% of the total bacterial protein, respectively. The two fusion proteins had a purity of about 85% and 90% after purification, and their purity reached 98% after purification with S-100 gel filtration chromatography. Both of the fusion proteins were efficiently immobilized on the surface of biotinylated mouse bladder cancer MB49 cells (91.3% for SA-hI-TAC and 98.8% for hI-TAC-SA). SA/hI-TAC induced lymphocyte chemotaxis in a dose-dependent manner, and hI-TAC-SA showed a stronger chemotactic effect than SA-hI-TAC.
  
  
  CONCLUSIONS
  We successfully obtained SA/hI-TAC bifunctional fusion proteins, which may potentially be used in local treatment of tumor and as a tumor vaccine.
authors.affiliation: Key Laboratory of Technology and Application of Model Organisms of Zhejiang Province, Wenzhou Medical University, Wenzhou 325035, China. E-mail: angieling@163.com.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Xu
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Qingge
authors.initials: Q
authors.lastname: Chen
authors.forename: Tongliang
authors.initials: T
authors.lastname: Huang
authors.forename: Jimin
authors.initials: J
authors.lastname: Gao
mesh_terms: D000818:Animals; D019921:Biotinylation; D015153:Blotting, Western; D019496:Cancer Vaccines; D045744:Cell Line, Tumor; D054371:Chemokine CXCL11 / Q000737:chemistry*; D002846:Chromatography, Affinity; D006801:Humans; D007372:Interferons / Q000737:chemistry*; D051379:Mice; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000737:chemistry*; D019809:Streptavidin
chemical_list: D019496:Cancer Vaccines; D054371:Chemokine CXCL11; D011993:Recombinant Fusion Proteins; D007372:Interferons; D019809:Streptavidin