{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Wouters Y"],"funding":["Geneeskundige Stichting Koningin Elisabeth","Fonds voor Wetenschappelijk Onderzoek (FWO) fellow","Vlaams Instituut voor Biotechnologie","Alzheimer&apos;s Association","Fonds voor Wetenschappelijk Onderzoek","Fonds voor Wetenschappelijk Onderzoek (FWO)","Vlaamse regering","Alzheimer’s Society","Medical Research Council","KU Leuven","Cure Alzheimer&apos;s Fund","Alzheimer’s Research UK","Alzheimer's Association"],"pagination":["79"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC9531356"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["19(1)"],"pubmed_abstract":["<h4>Background</h4>The blood brain barrier (BBB) limits the therapeutic perspective for central nervous system (CNS) disorders. Previously we found an anti-mouse transferrin receptor (TfR) VHH (Nb62) that was able to deliver a biologically active neuropeptide into the CNS in mice. Here, we aimed to test its potential to shuttle a therapeutic relevant cargo. Since this VHH could not recognize the human TfR and hence its translational potential is limited, we also aimed to find and validate an anti-human transferrin VHH to deliver a therapeutic cargo into the CNS.<h4>Methods</h4>Alpaca immunizations with human TfR, and subsequent phage selection and screening for human TfR binding VHHs was performed to find a human TfR specific VHH (Nb188). Its ability to cross the BBB was determined by fusing it to neurotensin, a neuropeptide that reduces body temperature when present in the CNS but is not able to cross the BBB on its own. Next, the anti-β-secretase 1 (BACE1) 1A11 Fab and Nb62 or Nb188 were fused to an Fc domain to generate heterodimeric antibodies (1A11AM-Nb62 and 1A11AM-Nb188). These were then administered intravenously in wild-type mice and in mice in which the murine apical domain of the TfR was replaced by the human apical domain (hAPI KI). Pharmacokinetic and pharmacodynamic (PK/PD) studies were performed to assess the concentration of the heterodimeric antibodies in the brain over time and the ability to inhibit brain-specific BACE1 by analysing the brain levels of Aβ<sub>1-40</sub>.<h4>Results</h4>Selections and screening of a phage library resulted in the discovery of an anti-human TfR VHH (Nb188). Fusion of Nb188 to neurotensin induced hypothermia after intravenous injections in hAPI KI mice. In addition, systemic administration 1A11AM-Nb62 and 1A11AM-Nb188 fusions were able to reduce Aβ<sub>1-40</sub> levels in the brain whereas 1A11AM fused to an irrelevant VHH did not. A PK/PD experiment showed that this effect could last for 3 days.<h4>Conclusion</h4>We have discovered an anti-human TfR specific VHH that is able to reach the CNS when administered systemically. In addition, both the currently discovered anti-human TfR VHH and the previously identified mouse-specific anti-TfR VHH, are both able to shuttle a therapeutically relevant cargo into the CNS. We suggest the mouse-specific VHH as a valuable research tool in mice and the human-specific VHH as a moiety to enhance the delivery efficiency of therapeutics into the CNS in human patients."],"journal":["Fluids and barriers of the CNS"],"pubmed_title":["VHHs as tools for therapeutic protein delivery to the central nervous system."],"pmcid":["PMC9531356"],"funding_grant_id":["S007918N","Grand Challenges","1S08516N","AARF-22-928639","UKDRI-Director01","Methusalem"],"pubmed_authors":["Dewilde M","Rue L","De Strooper B","Wouters Y","Jaspers T","Serneels L"],"additional_accession":[]},"is_claimable":false,"name":"VHHs as tools for therapeutic protein delivery to the central nervous system.","description":"<h4>Background</h4>The blood brain barrier (BBB) limits the therapeutic perspective for central nervous system (CNS) disorders. Previously we found an anti-mouse transferrin receptor (TfR) VHH (Nb62) that was able to deliver a biologically active neuropeptide into the CNS in mice. Here, we aimed to test its potential to shuttle a therapeutic relevant cargo. Since this VHH could not recognize the human TfR and hence its translational potential is limited, we also aimed to find and validate an anti-human transferrin VHH to deliver a therapeutic cargo into the CNS.<h4>Methods</h4>Alpaca immunizations with human TfR, and subsequent phage selection and screening for human TfR binding VHHs was performed to find a human TfR specific VHH (Nb188). Its ability to cross the BBB was determined by fusing it to neurotensin, a neuropeptide that reduces body temperature when present in the CNS but is not able to cross the BBB on its own. Next, the anti-β-secretase 1 (BACE1) 1A11 Fab and Nb62 or Nb188 were fused to an Fc domain to generate heterodimeric antibodies (1A11AM-Nb62 and 1A11AM-Nb188). These were then administered intravenously in wild-type mice and in mice in which the murine apical domain of the TfR was replaced by the human apical domain (hAPI KI). Pharmacokinetic and pharmacodynamic (PK/PD) studies were performed to assess the concentration of the heterodimeric antibodies in the brain over time and the ability to inhibit brain-specific BACE1 by analysing the brain levels of Aβ<sub>1-40</sub>.<h4>Results</h4>Selections and screening of a phage library resulted in the discovery of an anti-human TfR VHH (Nb188). Fusion of Nb188 to neurotensin induced hypothermia after intravenous injections in hAPI KI mice. In addition, systemic administration 1A11AM-Nb62 and 1A11AM-Nb188 fusions were able to reduce Aβ<sub>1-40</sub> levels in the brain whereas 1A11AM fused to an irrelevant VHH did not. A PK/PD experiment showed that this effect could last for 3 days.<h4>Conclusion</h4>We have discovered an anti-human TfR specific VHH that is able to reach the CNS when administered systemically. In addition, both the currently discovered anti-human TfR VHH and the previously identified mouse-specific anti-TfR VHH, are both able to shuttle a therapeutically relevant cargo into the CNS. We suggest the mouse-specific VHH as a valuable research tool in mice and the human-specific VHH as a moiety to enhance the delivery efficiency of therapeutics into the CNS in human patients.","dates":{"release":"2022-01-01T00:00:00Z","publication":"2022 Oct","modification":"2025-04-19T20:37:20.147Z","creation":"2025-04-19T20:37:20.147Z"},"accession":"S-EPMC9531356","cross_references":{"pubmed":["36192747"],"doi":["10.1186/s12987-022-00374-4"]}}