1
|
Konkle BA, Oldenburg J, Pasi J, Kulkarni R, Nolan B, Mahlangu J, Young G, Brown SA, Pabinger I, Shapiro A, Négrier C, Blanchette V, Ragni MV, Dumont J, Lethagen S. Prophylaxis with a recombinant factor VIII Fc in hemophilia A: long-term follow-up on joint health, efficacy, and safety from phase 3 studies in children and adults. Res Pract Thromb Haemost 2023; 7:102180. [PMID: 37753224 PMCID: PMC10518483 DOI: 10.1016/j.rpth.2023.102180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 06/28/2023] [Accepted: 07/13/2023] [Indexed: 09/28/2023] Open
Abstract
Background Recurrent joint bleeds are a major cause of morbidity in severe hemophilia. Prophylaxis with efmoroctocog alfa (a recombinant factor VIII Fc fusion protein, [rFVIIIFc]) has demonstrated benefits beyond bleed control, including joint health maintenance. Objectives To assess long-term efficacy and safety of rFVIIIFc prophylaxis in severe hemophilia A in phase 3 pivotal (A-LONG/Kids A-LONG) and extension (ASPIRE) studies. Methods Longitudinal analysis included pooled data from A-LONG/Kids A-LONG and ASPIRE. Subgroup analyses investigated outcomes in modified Hemophilia Joint Health Score or Hemophilia Joint Health Score and target joints in subjects with 4 to 5 years follow-up on individualized prophylaxis (IP), and those with the highest annualized bleeding rate (ABR) quartile during Year 1 of IP. Results Overall, rFVIIIFc consumption remained stable and low ABRs were maintained, with a median treatment duration of 4.2/3.4 years in subjects from A-LONG/Kids A-LONG, respectively. Median overall ABR also remained low (1.0-2.0) in subjects on IP for 4 to 5 years. Sustained improvements in modified Hemophilia Joint Health Score or Hemophilia Joint Health Score were demonstrated over a median follow-up of 3.7 years. In subjects from A-LONG/Kids A-LONG, 99.6% (n = 234)/100% (n = 9) of evaluable baseline target joints were resolved, with no recurrence in 95%/100% of target joints. In IP subjects within the highest ABR quartile in Year 1, continued improvements were observed over a median follow-up of 4.3 years in ABR and joint health, without increased factor consumption. No inhibitors or treatment-related serious adverse events were reported. Conclusion Previously treated subjects of all ages receiving long-term prophylaxis with rFVIIIFc had sustained clinical benefits, including improved joint health and low ABR.
Collapse
Affiliation(s)
- Barbara A. Konkle
- Washington Center for Bleeding Disorders, Seattle, Washington, USA
- Division of Hematology, University of Washington, Seattle, Washington, USA
| | - Johannes Oldenburg
- Institute of Experimental Hematology and Transfusion Medicine University Clinic Bonn, Bonn, Germany
| | - John Pasi
- Royal London Haemophilia Centre, Barts and the London School of Medicine and Dentistry, London, UK
| | - Roshni Kulkarni
- Department of Pediatrics and Human Development, Michigan State University, East Lansing, Michigan, USA
| | | | - Johnny Mahlangu
- Hemophilia Comprehensive Care Centre, Department of Molecular Medicine and Hematology, Faculty of Health Sciences, University of the Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa
| | - Guy Young
- Children’s Hospital Los Angeles, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Simon A. Brown
- Queensland Children’s Hospital, Brisbane, QLD, Australia
| | - Ingrid Pabinger
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Amy Shapiro
- Indiana Hemophilia & Thrombosis Center, Indianapolis, Indiana, USA
| | - Claude Négrier
- Division of Hematology, University Claude Bernard Lyon I, Lyon, France
| | - Victor Blanchette
- Department of Pediatrics and Child Health Evaluative Sciences, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Margaret V. Ragni
- Department of Medicine, Division of Hematology/Oncology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | | | - Stefan Lethagen
- Swedish Orphan Biovitrum AB, Stockholm, Sweden
- Copenhagen University, Copenhagen, Denmark
| |
Collapse
|
2
|
Li C, Xie Y, Cao J, Shao J. [Construction, expression and purification of a mammalian secretory recombinant fusion protein rPC]. Sheng Wu Gong Cheng Xue Bao 2020; 36:969-978. [PMID: 32567280 DOI: 10.13345/j.cjb.190405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Drugs targeting immune checkpoint are used for cancer treatment, but resistance to single drug may occur. Combination therapy blocking multiple checkpoints simultaneously can improve clinical outcome. Therefore, we designed a recombinant protein rPC to block multiple targets, which consists of extracellular domains of programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4). The coding sequence was inserted into expression vector and stably transfected into HEK293 cells. The culture supernatant was collected and rPC was affinity-purified. Real-time quantitative PCR was used to evaluate the expression levels of ligands for PD-1 and CTLA-4 in several human cancer cell lines. The binding of rPC with cancer cells was examined by immunofluorescence cell staining, the influence of rPC on cancer cell growth was assayed by CCK-8. The results showed that rPC could be expressed and secreted by stably transfected HEK293 cells, the purified rPC could bind to lung cancer NCI-H226 cells which have high levels of ligands for PD-1 and CTLA-4, no direct impact on cancer cell growth could be observed by rPC treatment. The recombinant protein rPC can be functionally assayed further for developing novel immunotherapeutic drugs for cancer.
Collapse
Affiliation(s)
- Chunchun Li
- Clinical Research Center, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, Zhejiang, China
| | - Yuqiong Xie
- Clinical Research Center, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, Zhejiang, China
| | - Jiang Cao
- Clinical Research Center, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, Zhejiang, China
| | - Jimin Shao
- Department of Pathology and Pathophysiology, Zhejiang University School of Medicine, Hangzhou 310058, Zhejiang, China
| |
Collapse
|
3
|
Sakhnini LI, Pedersen AK, Dainiak MB, Bülow L. Multimeric fusion single-chain variable fragments as potential novel high-capacity ligands. FEBS Open Bio 2020; 10:507-514. [PMID: 31950675 PMCID: PMC7137789 DOI: 10.1002/2211-5463.12789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/24/2019] [Accepted: 01/10/2020] [Indexed: 12/17/2022] Open
Abstract
In basic and applied biotechnology, design of affinity ligands has become essential for high-capacity applications such as affinity-based downstream processes for therapeutic molecules. Here, we established a proof-of-concept for the use of multimeric fusion single-chain variable fragment (scFvs) as high-capacity ligands in affinity adsorbents. Mono- and di/tri-scFvs separated by Pro-rich negatively charged linkers were designed, produced, and immobilized to 6% cross-linked agarose beads. Frontal binding experiments with a target protein of 50 kDa resulted in up to 20 mg·mL-1 and 82% in dynamic binding capacity and utilization yield, respectively, at 100% breakthrough. The utilization of the binding sites was impacted by the ligand format and ligand density, rather than limitation in pore size of adsorbent as previously suggested. Overall, we demonstrated that multimeric fusion scFvs can successfully be developed and used as high-capacity ligands in affinity adsorbents, enabling lean process design and alignment with process specifications.
Collapse
Affiliation(s)
- Laila I. Sakhnini
- Global Research TechnologiesNovo Nordisk A/SCopenhagenDenmark
- Division of Pure and Applied BiochemistryLund UniversityLundSweden
| | - Anja K. Pedersen
- Chemistry, Manufacturing and ControlNovo Nordisk A/SCopenhagenDenmark
| | | | - Leif Bülow
- Division of Pure and Applied BiochemistryLund UniversityLundSweden
| |
Collapse
|
4
|
Chua SJ, Morton MR, Svigos J, Ross DM, Kane S. Use of romiplostim in pregnancy for refractory idiopathic thrombocytopenic purpura: Two case reports with maternal and fetal outcomes and literature review. Obstet Med 2020; 13:45-50. [PMID: 32284733 PMCID: PMC7133099 DOI: 10.1177/1753495x18773960] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 03/30/2018] [Indexed: 12/30/2022] Open
Abstract
Idiopathic thrombocytopenic purpura is a relatively rare complication occurring in pregnancy, with the potential for serious maternal and fetal outcomes. Rarely, the poor response to established first-line therapies results in consideration of second-line therapies, which may have poorly understood risks to the fetus. We report two women with severe idiopathic thrombocytopenic purpura during pregnancy unresponsive to corticosteroids and intravenous immunoglobulin who were treated with romiplostim, a thrombopoietin receptor agonist. One woman with chronic idiopathic thrombocytopenic purpura had a partial response to romiplostim and suffered a post-partum haemorrhage related to uterine atony. The second woman developed severe idiopathic thrombocytopenic purpura in pregnancy and initially responded well to romiplostim. However, a lower segment Caesarean section was performed at 37 weeks for pre-eclampsia. The newborn suffered from severe idiopathic thrombocytopenic purpura and a grade 1 cerebral haemorrhage requiring intravenous immunoglobulin and platelet transfusions. Romiplostim might be a useful therapy for severe idiopathic thrombocytopenic purpura in pregnancy but requires further study.
Collapse
Affiliation(s)
- Su J Chua
- Women’s
& Children’s Hospital, North
Adelaide, Australia
| | - Mark R Morton
- Women’s
& Children’s Hospital, North
Adelaide, Australia
| | - John Svigos
- Women’s
& Children’s Hospital, North
Adelaide, Australia
| | - David M Ross
- Department of Haematology,
Royal
Adelaide Hospital, Adelaide,
Australia
| | - Simon Kane
- Lyell
McEwin Hospital, Elizabeth Vale,
Australia
| |
Collapse
|
5
|
Fathi S, Jalousian F, Hosseini SH, Najafi A, Darabi E, Koohsar F. Design and construction of a new recombinant fusion protein (2b2t+EPC1) and its assessment for serodiagnosis of cystic echinococcosis. APMIS 2018; 126:428-439. [PMID: 29696723 DOI: 10.1111/apm.12838] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 03/14/2018] [Indexed: 12/31/2022]
Abstract
The immunodiagnostic tests for cystic echinococcosis (CE) are mostly serological tests based on ELISA that use hydatid cyst antigens for primary screening because of its simple preparation and availability. The challenge to develop new serological methods (as compared to those based on the hydatid cyst fluid antigens) to meet the gold standard remains. Appropriate sources of antigenic material are necessary for application to improve the efficacy of immunodiagnostic tests at a population level. In the current study, a fusion protein containing the coding sequence of antigen B2t and two sequences of EPC1 antigen with some modifications was reconstructed. Using bioinformatics tools, these sequences were joined together by applying the sequence of a rigid α-helix-forming linker to obtain an appropriate structure of a fusion protein. Synthetic recombinant fusion protein was expressed using pET28a as a vector and evaluated by indirect ELISA test for sera from patients with hepatic CE and other parasitic infections. The sensitivity of the fusion protein was lower (88.46%) than the available ELISA kit (96.15%). However, the differences in sensitivity were not statistically significant as compared to the recombinant fusion peptide with the commercial kit (p = 0.269). The specificity of the recombinant fusion protein (95.45%) was not significantly lower than the commercial kit (96.59%; p = 1.000). Moreover, surprisingly there was no difference in the cross-reactivity values of performance between the recombinant-ELISA and commercial kit. The positive and negative predictive values of the recombinant antigen were achieved as 92% and 93.33%, respectively, while for the commercial kit, they were obtained as 94.33% and 97.70%, respectively. In conclusion, as an early evaluation of these antigens the performance of our recombinant fusion protein in ELISA is relatively promising. Although, it seemed that this peptide with specific antigenic epitopes might be more appropriate for the serological evaluation of CE by use of bioinformatics tools, our findings showed that cross-reactions and a negative reaction could occur in clinical performance. This fusion protein may have utility for diagnosis in humans, but further evaluation is needed using the WHO ultrasound classification for CE.
Collapse
Affiliation(s)
- Saeid Fathi
- Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - Fatemeh Jalousian
- Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - Seyed Hossein Hosseini
- Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - Ali Najafi
- Molecular Biology Research Center, Systems Biology and Poisoning Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Enayat Darabi
- Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Faramarz Koohsar
- Paramedical Faculty, Golestan University of Medical Sciences, Gorgan, Iran
| |
Collapse
|
6
|
Nematollahi MH, Torkzadeh-Mahanai M, Pardakhty A, Ebrahimi Meimand HA, Asadikaram G. Ternary complex of plasmid DNA with NLS-Mu-Mu protein and cationic niosome for biocompatible and efficient gene delivery: a comparative study with protamine and lipofectamine. Artif Cells Nanomed Biotechnol 2017; 46:1781-1791. [PMID: 29081256 DOI: 10.1080/21691401.2017.1392316] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Non-viral gene delivery methods are considered due to safety and simplicity in human gene therapy. Since the use of cationic peptide and niosome represent a promising approach for gene delivery purposes we used recombinant fusion protein and cationic niosome as a gene carrier. A multi-domain fusion protein including nuclear localization motif (NLS) and two DNA-binding (Mu) domains, namely NLS-Mu-Mu (NMM) has been designed, cloned and expressed in E. coli DE3 strain. Afterward, the interested protein was purified by affinity chromatography. Binary vectors based on protein/DNA and ternary vectors based on protein/DNA/niosome were prepared. Protamine was used as a control. DNA condensing properties of NMM and protamine were evaluated by various experiments. Furthermore, we examined cytotoxicity, hemolysis and transfection potential of the binary and ternary complexes in HEK293T and MCF-7 cell lines. Protamine and Lipofectamine™2000 were used as positive controls, correspondingly. The recombinant NMM was expressed and purified successfully and DNA was condensed efficiently at charge ratios that were not harmful to cells. Peptidoplexes showed transfection efficiency (TE) but ternary complexes had higher TE. Additionally, NMM ternary complex was more efficient compared to protamine ternary vectors. Our results showed that niosomal ternary vector of NMM is a promising non-viral gene carrier to achieve an effective and safe carrier system for gene therapy.
Collapse
Affiliation(s)
- Mohammad Hadi Nematollahi
- a Neurology Research Center , Kerman University of Medical Sciences , Kerman , Iran.,b Department of Biochemistry, School of Medicine , Kerman University of Medical Sciences , Kerman , Iran
| | - Masoud Torkzadeh-Mahanai
- c Biotechnology Department, Institute of Science and High Technology and Environmental Sciences , Graduate University of Advanced Technology , Kerman , Iran
| | - Abbas Pardakhty
- d Pharmaceutics Research Center, Institute of Neuropharmacology , Kerman University of Medical Science , Kerman , Iran
| | | | - Gholamreza Asadikaram
- b Department of Biochemistry, School of Medicine , Kerman University of Medical Sciences , Kerman , Iran.,e Neuroscience Research Center, Institute of Neuropharmacology , Kerman University of Medical Sciences , Kerman , Iran
| |
Collapse
|
7
|
Abstract
Fusion proteins can be used directly in protein crystallization to assist crystallization in at least two different ways. In one approach, the `heterologous fusion-protein approach', the fusion partner can provide additional surface area to promote crystal contact formation. In another approach, the `fusion of interacting proteins approach', protein assemblies can be stabilized by covalently linking the interacting partners. The linker connecting the proteins plays different roles in the two applications: in the first approach a rigid linker is required to reduce conformational heterogeneity; in the second, conversely, a flexible linker is required that allows the native interaction between the fused proteins. The two approaches can also be combined. The recent applications of fusion-protein technology in protein crystallization from the work of our own and other laboratories are briefly reviewed.
Collapse
Affiliation(s)
- Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Simon J. Williams
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Queensland 4072, Australia
- School of Biological Sciences, Flinders University, Adelaide, South Australia 5001, Australia
| |
Collapse
|
8
|
Powell J, Shapiro A, Ragni M, Negrier C, Windyga J, Ozelo M, Pasi J, Baker R, Potts J, Li S, Mei B, Pierce GF, Robinson B. Switching to recombinant factor IX Fc fusion protein prophylaxis results in fewer infusions, decreased factor IX consumption and lower bleeding rates. Br J Haematol 2015; 168:113-23. [PMID: 25209873 DOI: 10.1111/bjh.13109] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 07/29/2014] [Indexed: 01/25/2023]
Abstract
In the phase 3 B-LONG [Recombinant Factor IX Fc Fusion Protein (rFIXFc) in Subjects with Haemophilia B] study, rFIXFc dosed every 1-2 weeks was safe and efficacious in previously treated subjects with haemophilia B. To date, there are no evaluations of transitioning from conventional to long-acting factor IX (FIX) prophylaxis. This post-hoc analysis of B-LONG subjects compared prophylaxis with other FIX products and rFIXFc. Pre- and on-study data were analysed to assess dosing regimen, weekly FIX consumption and annualized bleeding rates (ABRs). Population pharmacokinetics models were used to generate FIX activity profiles with rFIXFc and recombinant FIX prophylaxis. Thirty-nine subjects, previously treated prophylactically, were evaluated. Prior to study, most subjects (69·2%) received twice-weekly FIX infusions; on study, subjects infused rFIXFc once every 1-2 weeks with c. 30-50% reductions in weekly consumption. On-study estimated mean ABRs were lower than pre-study estimated mean ABRs. Models predicted that rFIXFc administered 50 iu/kg weekly and 100 iu/kg every 10 d would maintain steady-state FIX trough levels ≥1 iu/dl in 95·4% and 89·2% of subjects, respectively. These results indicate that patients receiving rFIXFc prophylaxis can markedly reduce infusion frequency and FIX consumption, have a greater likelihood of maintaining FIX activity >1 iu/dl and experience fewer bleeding episodes compared with prior FIX prophylaxis.
Collapse
Affiliation(s)
- Jerry Powell
- University of California Davis, Sacramento, CA, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Dong L, Zhang X, Yu C, Ren J, Hou L, Fu L, Yi S, Chen W. Expression and purification of recombinant proteins based on human prostate stem cell antigen and heat shock protein-70. Exp Ther Med 2013; 5:1161-1164. [PMID: 23596484 PMCID: PMC3627452 DOI: 10.3892/etm.2013.967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 02/05/2013] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to express and purify recombinant proteins based on human prostate stem cell antigen (PSCA) and heat shock protein-70 (HSP70). The PSCA gene and various structural domains of HSP70 were amplified by polymerase chain reaction (PCR) with the respective primers. Then, the PSCA was cloned into the prokaryotic expression vector pET21a(+) with the amino-terminus, carboxyl-terminus and overall length of HSP70, by enzyme digestion to construct the recombinant plasmids pET21-PSCA-HSPN, pET21-PSCA-HSPC and pET21-PSCA-HSP, respectively. After being expressed in Escherichia coli (E. coli) by isopropyl β-D-1-thiogalactopyranoside (IPTG) induction, recombinant fusion proteins were purified. Western blotting was performed to confirm the expression of the recombinant proteins. The results revealed that recombinant plasmids were successfully constructed. The PSCA-HSPC and PSCA-HSP expressed in E. coli existed in soluble form, as confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The purity of the recombinant proteins PSCA-HSPC and PSCA-HSP reached >95% following purification with the nickel-nitrilotriacetic acid (Ni-NTA) resin, Phenyl-Sepharose Fast Flow and Superdex 75, which lays a foundation for the development of vaccines for prostate cancer.
Collapse
Affiliation(s)
- Lei Dong
- Clinical Laboratory Center, PLA Air Force General Hospital, Haidian, Beijing 100142, P.R. China
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Bauer S, Adrian N, Siebenborn U, Fadle N, Plesko M, Fischer E, Wüest T, Stenner F, Mertens JC, Knuth A, Ritter G, Old LJ, Renner C. Sequential cancer immunotherapy: targeted activity of dimeric TNF and IL-8. Cancer Immun 2009; 9:2. [PMID: 19267427 PMCID: PMC2935764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 02/11/2009] [Indexed: 05/27/2023]
Abstract
Polymorphonuclear neutrophils (PMNs) are potent effectors of inflammation and their attempts to respond to cancer are suggested by their systemic, regional and intratumoral activation. We previously reported on the recruitment of CD11b+ leukocytes due to tumor site-specific enrichment of TNF activity after intravenous administration of a dimeric TNF immunokine with specificity for fibroblast activation protein (FAP). However, TNF-induced chemo-attraction and extravasation of PMNs from blood into the tumor is a multistep process essentially mediated by interleukin 8. With the aim to amplify the TNF-induced and IL-8-mediated chemotactic response, we generated immunocytokines by N-terminal fusion of a human anti-FAP scFv fragment with human IL-8 (IL-8(72)) and its N-terminally truncated form IL-8(3-72). Due to the dramatic difference in chemotaxis induction in vitro, we favored the mature chemokine fused to the anti-FAP scFv for further investigation in vivo. BALB/c nu/nu mice were simultaneously xenografted with FAP-positive or -negative tumors and extended chemo-attraction of PMNs was only detectable in FAP-expressing tissue after intravenous administration of the anti-FAP scFv-IL-8(72) construct. As TNF-activated PMNs are likewise producers and primary targets for IL-8, we investigated the therapeutic efficacy of co-administration of both effectors: Sequential application of scFv-IL-8(72) and dimeric IgG1-TNF fusion proteins significantly enhanced anti-tumor activity when compared either to a single effector treatment regimen or sequential application of non-targeted cytokines, indicating that the tumor-restricted sequential application of IL-8(72) and TNF is a promising approach for cancer therapy.
Collapse
Affiliation(s)
- Stefan Bauer
- Oncology Department, University Hospital Zurich, Zurich, Switzerland.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|