title: Fusion to an albumin-binding domain with a high affinity for albumin extends the circulatory half-life and enhances the in vivo antitumor effects of human TRAIL.
abstract: Clinical applications of recombinant human tumor necrosis factor-related apoptosis-inducing ligand (hTRAIL) have been limited by their poor pharmacokinetics. Using endogenous albumin as a carrier is an attractive approach for circulatory half-life extension. Here, we produced ABD-hTRAIL and hTRAIL-ABD by fusing the albumin-binding domain (ABD) from protein G to the N- or C-terminus of hTRAIL. We found that ABD-hTRAIL bound human serum albumin (HSA) with a high affinity (0.4 ± 0.18 nM) and formed nanoparticles with an average diameter (~12 nm) above the threshold (~7 nm) of renal filtration. ABD-hTRAIL also bound mouse serum albumin (MSA); thus, its half-life was 40-50-fold greater than that of hTRAIL (14.1 ± 0.87 h vs 0.32 ± 0.14 h). Tumor uptake of ABD-hTRAIL 8-48 h post-injection was 6-16-fold that of hTRAIL. Consequently, the tumor suppression of ABD-hTRAIL in mice bearing subcutaneous xenografts was 3-4 times greater than that of hTRAIL. Additionally, the time period during which ABD-hTRAIL could kill circulating tumor cells was approximately 8 times longer than that of hTRAIL. These results demonstrate that ABD fused to the N-terminus endows hTRAIL with albumin binding ability; once it enters the vasculature, ABD mediates binding with endogenous albumin, thus prolonging the half-life and enhancing the antitumor effect of hTRAIL. However, hTRAIL-ABD did not show a high affinity for albumin and therefore did not display the prolonged circulatory half-life and enhanced antitumor effects. These results demonstrate that N-terminal, but not C-terminal, ABD-fusion is an efficient technique for enhancing the antitumor effects of hTRAIL by using endogenous albumin as a carrier.
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China; Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Yang
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China; Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Dianlong
authors.initials: D
authors.lastname: Jia
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Qianxue
authors.initials: Q
authors.lastname: Nie
authors.affiliation: Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Huawei
authors.initials: H
authors.lastname: Cai
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Fan
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wan
authors.affiliation: Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu 610041, China. Electronic address: xiaofenglu@yahoo.com.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Lu
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D006207:Half-Life; D006801:Humans; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics / Q000627:therapeutic use; D012709:Serum Albumin / Q000378:metabolism*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics* / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D011993:Recombinant Fusion Proteins; D012709:Serum Albumin; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human
keywords: Albumin; Albumin-binding domain; Anti-cancer drug; Cancer biotherapy; Drug delivery; Tumor necrosis factor-related apoptosis-inducing ligand