Differences in wild-type- and R338L-tenase complex formation are at the root of R338L-factor IX assay discrepancies.
Journal
Blood advances
ISSN: 2473-9537
Titre abrégé: Blood Adv
Pays: United States
ID NLM: 101698425
Informations de publication
Date de publication:
14 02 2023
14 02 2023
Historique:
accepted:
01
07
2022
received:
28
02
2022
pubmed:
16
7
2022
medline:
9
2
2023
entrez:
15
7
2022
Statut:
ppublish
Résumé
Adeno-associated virus (AAV) gene therapy has the potential to functionally cure hemophilia B by restoring factor (F)IX concentrations into the normal range. Next-generation AAV therapies express a naturally occurring gain-of-function FIX variant, FIX-Padua (R338L-FIX), that increases FIX activity (FIX:C) by approximately eightfold compared with wild-type FIX (FIX-WT). Previous studies have shown that R338L-FIX activity varies dramatically across different clinical FIX:C assays, which complicates the monitoring and management of patients. To better understand mechanisms that contribute to R338L-FIX assay discrepancies, we characterized the performance of R338L-FIX in 13 1-stage clotting assays (OSAs) and 2 chromogenic substrate assays (CSAs) in a global field study. This study produced the largest R338L-FIX assay dataset to date and confirmed that clinical FIX:C assay results vary over threefold. Both phospholipid and activating reagents play a role in OSA discrepancies. CSA generated the most divergent FIX:C results. Manipulation of FIX:C CSA kits demonstrated that specific activity gains for R338L-FIX were most profound at lower FIX:C concentrations and that these effects were enhanced during the early phases of FXa generation. Supplementing FX into CSA had the effect of dampening FIX-WT activity relative to R338L-FIX activity, suggesting that FX impairs WT tenase formation to a greater extent than R338L-FIX tenase. Our data describe the scale of R338L-FIX assay discrepancies and provide insights into the causative mechanisms that will help establish best practices for the measurement of R338L-FIX activity in patients after gene therapy.
Identifiants
pubmed: 35839077
pii: 485933
doi: 10.1182/bloodadvances.2022007435
pmc: PMC9979717
doi:
Substances chimiques
Factor IX
9001-28-9
cancer procoagulant
EC 3.4.22.26
Cysteine Endopeptidases
EC 3.4.22.-
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
458-467Informations de copyright
© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.
Références
Int J Hematol. 2019 Apr;109(4):390-401
pubmed: 30756344
N Engl J Med. 2009 Oct 22;361(17):1671-5
pubmed: 19846852
J Thromb Haemost. 2021 May;19(5):1212-1218
pubmed: 33636038
Blood Transfus. 2014 Jul;12(3):314-9
pubmed: 25074524
Hematology Am Soc Hematol Educ Program. 2019 Dec 6;2019(1):1-8
pubmed: 31808868
JCI Insight. 2019 Jun 20;5:
pubmed: 31219805
Thromb Haemost. 2015 Mar;113(3):599-604
pubmed: 25338662
Blood. 2018 Mar 1;131(9):1022-1031
pubmed: 29246900
N Engl J Med. 2011 Dec 22;365(25):2357-65
pubmed: 22149959
Blood. 2017 Oct 5;130(14):1661-1670
pubmed: 28729433
N Engl J Med. 2017 Dec 7;377(23):2215-2227
pubmed: 29211678
Mol Ther Methods Clin Dev. 2018 Dec 31;12:184-201
pubmed: 30705923
Blood Adv. 2019 Nov 12;3(21):3241-3247
pubmed: 31698454
J Thromb Haemost. 2016 Jul;14(7):1428-35
pubmed: 27107268
J Thromb Haemost. 2010 Jul;8(7):1532-9
pubmed: 20456758
Haemophilia. 2009 Jan;15(1):63-72
pubmed: 18691375
Thromb Haemost. 2014 Nov;112(5):932-40
pubmed: 25144892
N Engl J Med. 2014 Nov 20;371(21):1994-2004
pubmed: 25409372
Sci Rep. 2019 Oct 29;9(1):15449
pubmed: 31664102
Transfus Apher Sci. 2019 Oct;58(5):596-600
pubmed: 31421983