Heparin-binding motif mutations of human diamine oxidase allow the development of a first-in-class histamine-degrading biopharmaceutical
Abstract
Background: Excessive plasma histamine concentrations cause symptoms in mast cell activation syndrome, mastocytosis or anaphylaxis. Anti-histamines are often insufficiently efficacious. Human diamine oxidase (hDAO) can rapidly degrade histamine and therefore represents a promising new treatment strategy for conditions with pathological histamine concentrations.
Results: Recombinant hDAO is rapidly cleared from the circulation in rats and mice. After replacement of positively charged amino acids of the heparin-binding motif with polar serine or threonine residues binding to heparin and heparan sulfate was strongly reduced. The double mutant rhDAO-R568S/R571T showed minimal cellular uptake. The short α-distribution half-life of the wildtype protein was eliminated and the clearance was significantly reduced in rodents.
Conclusions: The successful decrease in plasma clearance of rhDAO by mutations of the heparin-binding motif with unchanged histamine-degrading activity represents the first step towards the development of rhDAO as a first-in-class biopharmaceutical to effectively treat diseases characterized by excessive histamine concentrations in plasma and tissues.
Funding: Austrian Science Fund (FWF) Hertha Firnberg program grant T1135 (EG); ADD funding Sigrid Juselius Foundation, Medicinska Understödsförening Liv och Hälsa rft (TAS and SeV).
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2 and 3.
Article and author information
Author details
Funding
Austrian Science Fund (T1135)
- Elisabeth Gludovacz
Sigrid Juséliuksen Säätiö
- Serhii Vakal
- Tiina A Salminen
Medicinska Understödsföreningen Liv och Hälsa
- Serhii Vakal
- Tiina A Salminen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Arduino A Mangoni, Flinders Medical Centre, Australia
Ethics
Animal experimentation: The experimental protocols for the treatment of rats and mice were approved by the local Animal Welfare Committee and the Federal Ministry of Science, Research and Economy (GZ 66.009/0152-WF/V/3b/2014) and conducted in full accordance with the ARRIVE guidelines.
Version history
- Received: March 18, 2021
- Accepted: September 1, 2021
- Accepted Manuscript published: September 3, 2021 (version 1)
- Version of Record published: September 16, 2021 (version 2)
- Version of Record updated: September 29, 2021 (version 3)
Copyright
© 2021, Gludovacz et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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