PXD068424

PXD068424 is an original dataset announced via ProteomeXchange.

Title	MHC class II presentation of FVIII-AnnexinA5 fusion proteins internalized by antigen presenting cells
Description	The development of neutralizing antibodies (inhibitors) against coagulation factor VIII (FVIII) remains the most serious complication in the treatment of hemophilia A. While immune tolerance induction (ITI) is the standard strategy to eliminate these antibodies, it fails in approximately 30% of patients with severe hemophilia A, underscoring the need for innovative approaches to promote FVIII-specific tolerance. To address this challenge, we generated fusion proteins composed of A2, A3-C1-C2 (light chain, LCh), and C2 domains of FVIII linked to Annexin A5 (AnxA5), a protein that binds phosphatidylserine (PS), a hallmark of apoptotic cells. ELISA confirmed high-affinity binding of all fusion proteins to immobilized PS. To model PS exposure in vitro, red blood cells (RBCs) were treated with phorbol 12-myristate 13-acetate (PMA), leading to the release of PS-exposing microvesicles. Flow cytometry showed that FVIII-AnxA5 fusion proteins selectively bound to PS-exposing microvesicles but not to intact RBCs. Using mass spectrometry-based immunopeptidomics, we demonstrated that macrophages pulsed with FVIII-AnxA5 fusion proteins efficiently processed and presented FVIII-derived peptides on HLA-DR molecules. These findings suggest that FVIII-AnxA5 fusion proteins can engage apoptotic cell clearance pathways to facilitate antigen presentation in a potentially tolerogenic context. This strategy may offer a novel means of inducing immune tolerance to FVIII in hemophilia A.
HostingRepository	PRIDE
AnnounceDate	2025-10-20
AnnouncementXML	Submission_2025-10-19_16:37:20.780.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Arie Hoogendijk
SpeciesList	scientific name: Homo sapiens (Human); NCBI TaxID: NEWT:9606;
ModificationList	monohydroxylated residue
Instrument	Orbitrap Fusion Lumos

Revision	Datetime	Status	ChangeLog Entry
0	2025-09-16 12:47:43	ID requested
⏵ 1	2025-10-19 16:37:21	announced

Miranda M, Leoni M, van der Zwaan C, van Bruggen R, Reutelingsperger CPM, Fijnvandraat K, Hoogendijk AJ, van den Biggelaar M, Voorberg J, MHC class II presentation of FVIII-AnnexinA5 fusion proteins internalized by antigen presenting cells. Front Immunol, 16():1668397(2025) [pubmed]

10.3389/fimmu.2025.1668397;

submitter keyword: Annexin A5, Phosphatidylserine, immune response,FVIII, antigen presentation

A.J. Hoogendijk
contact affiliation	Laboratory of mass spectrometry, Sanquin Research, Amsterdam, NL
contact email	a.hoogendijk@sanquin.nl
lab head
Arie Hoogendijk
contact affiliation	Sanquin Research, Amsterdam
contact email	a.hoogendijk@sanquin.nl
dataset submitter

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PRIDE project URI

• PRIDE
  1. PXD068424
     1. Label: PRIDE project
     2. Name: MHC class II presentation of FVIII-AnnexinA5 fusion proteins internalized by antigen presenting cells