Evidence map›Paper›PMID 42827696›Full record

ArticleBlood vessels, thrombosis & hemostasis2026

Decoding full-length factor VIII through the structural and functional lens of its B domain.

Samhitha Urs Ramaraje Urs, Jean-Luc Pellequer, Jean-Marie Teulon, Boxue Ma, Deniz Ugurlar, Simone Gasper, Anna Pepanian, Jens Müller, Diana Imhof, Sneha Singh and 2 more

Abstract read
In one paragraph

Article in Blood vessels, thrombosis & hemostasis, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Trial
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Samhitha Urs Ramaraje UrsInstitute of Experimental Hematology and Transfusion Medicine, University Hospital of Bonn, Bonn, Germany.
Jean-Luc PellequerInstitut de Biologie Structurale, Université Grenoble Alpes, French Alternative Energies and Atomic Energy Commission, French National Center for Scientific Research, Grenoble, France.
Jean-Marie TeulonInstitut de Biologie Structurale, Université Grenoble Alpes, French Alternative Energies and Atomic Energy Commission, French National Center for Scientific Research, Grenoble, France.
Boxue MaCryo-Electron Microscopy Unit, Thermo Fisher Scientific, Eindhoven, The Netherlands.
Deniz UgurlarCryo-Electron Microscopy Unit, Thermo Fisher Scientific, Eindhoven, The Netherlands.
Simone GasperInstitute of Experimental Hematology and Transfusion Medicine, University Hospital of Bonn, Bonn, Germany.
Anna PepanianPharmaceutical Institute, University of Bonn, Bonn, Germany.
Jens MüllerInstitute of Experimental Hematology and Transfusion Medicine, University Hospital of Bonn, Bonn, Germany.
Diana ImhofPharmaceutical Institute, University of Bonn, Bonn, Germany.
Sneha SinghInstitute of Experimental Hematology and Transfusion Medicine, University Hospital of Bonn, Bonn, Germany.
Johannes OldenburgInstitute of Experimental Hematology and Transfusion Medicine, University Hospital of Bonn, Bonn, Germany.
Arijit BiswasInstitute of Experimental Hematology and Transfusion Medicine, University Hospital of Bonn, Bonn, Germany.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The factor VIII (FVIII) B domain, a large and heavily glycosylated region, is crucial for FVIII secretion, although its structural and functional roles remain incompletely understood. Although the B domain is dispensable for cofactor activity, previous research hints at multiple, yet unverified, functional roles. Here, we used an integrative hybrid approach to generate detailed structural models of glycosylated and furin-cleaved full-length FVIII (Gly/FC-FL-FVIII) that include the B domain, using AlphaFold2 predictions. These models were further refined and validated with biophysical data from atomic force microscopy (AFM) and cryogenic electron microscopy of recombinant and plasma-derived FL-FVIII proteins. Additionally, we modeled a FL-FVIII-von Willebrand factor (VWF) complex with both the B domain and D'-D3 domains to investigate B-domain interactions during intracellular processing. Our results suggest that the B domain functions largely as an independent domain encircling the FVIII core. AFM studies revealed that VWF tails are associated with globular FVIII structures. Structural analysis indicated that B-domain glycosylation enhances stability, supports proper folding, and promotes efficient trafficking through the endoplasmic reticulum-Golgi pathway. We propose that, within the Golgi, the B domain may unfold around FVIII via furin cleavages, facilitating essential interactions with partners such as VWF. Our models also suggest that the B domain shields key FVIII epitopes, potentially reducing immune interference and inhibiting premature activation. This study presents a novel structural model of the FVIII B domain and FL-FVIII, offering critical insights into previously unexplored aspects of B-domain function and its essential role in FVIII biology.

Identifiers

PMID42827696
PMCPMC13631594

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.