Secreted mutant calreticulins as rogue cytokines in myeloproliferative neoplasms

© 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..

Mutant calreticulin (CALR) proteins resulting from a -1/+2 frameshifting mutation of the CALR exon 9 carry a novel C-terminal amino acid sequence and drive the development of myeloproliferative neoplasms (MPNs). Mutant CALRs were shown to interact with and activate the thrombopoietin receptor (TpoR/MPL) in the same cell. We report that mutant CALR proteins are secreted and can be found in patient plasma at levels up to 160 ng/mL, with a mean of 25.64 ng/mL. Plasma mutant CALR is found in complex with soluble transferrin receptor 1 (sTFR1) that acts as a carrier protein and increases mutant CALR half-life. Recombinant mutant CALR proteins bound and activated the TpoR in cell lines and primary megakaryocytic progenitors from patients with mutated CALR in which they drive thrombopoietin-independent colony formation. Importantly, the CALR-sTFR1 complex remains functional for TpoR activation. By bioluminescence resonance energy transfer assay, we show that mutant CALR proteins produced in 1 cell can specifically interact in trans with the TpoR on a target cell. In comparison with cells that only carry TpoR, cells that carry both TpoR and mutant CALR are hypersensitive to exogenous mutant CALR proteins and respond to levels of mutant CALR proteins similar to those in patient plasma. This is consistent with CALR-mutated cells that expose TpoR carrying immature N-linked sugars at the cell surface. Thus, secreted mutant CALR proteins will act more specifically on the MPN clone. In conclusion, a chaperone, CALR, can turn into a rogue cytokine through somatic mutation of its encoding gene.

Errataetall:

CommentIn: Blood. 2023 Feb 23;141(8):818-820. - PMID 36821187

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:141

Enthalten in:

Blood - 141(2023), 8 vom: 23. Feb., Seite 917-929

Sprache:

Englisch

Beteiligte Personen:

Pecquet, Christian [VerfasserIn]
Papadopoulos, Nicolas [VerfasserIn]
Balligand, Thomas [VerfasserIn]
Chachoua, Ilyas [VerfasserIn]
Tisserand, Amandine [VerfasserIn]
Vertenoeil, Gaëlle [VerfasserIn]
Nédélec, Audrey [VerfasserIn]
Vertommen, Didier [VerfasserIn]
Roy, Anita [VerfasserIn]
Marty, Caroline [VerfasserIn]
Nivarthi, Harini [VerfasserIn]
Defour, Jean-Philippe [VerfasserIn]
El-Khoury, Mira [VerfasserIn]
Hug, Eva [VerfasserIn]
Majoros, Andrea [VerfasserIn]
Xu, Erica [VerfasserIn]
Zagrijtschuk, Oleh [VerfasserIn]
Fertig, Tudor E [VerfasserIn]
Marta, Daciana S [VerfasserIn]
Gisslinger, Heinz [VerfasserIn]
Gisslinger, Bettina [VerfasserIn]
Schalling, Martin [VerfasserIn]
Casetti, Ilaria [VerfasserIn]
Rumi, Elisa [VerfasserIn]
Pietra, Daniela [VerfasserIn]
Cavalloni, Chiara [VerfasserIn]
Arcaini, Luca [VerfasserIn]
Cazzola, Mario [VerfasserIn]
Komatsu, Norio [VerfasserIn]
Kihara, Yoshihiko [VerfasserIn]
Sunami, Yoshitaka [VerfasserIn]
Edahiro, Yoko [VerfasserIn]
Araki, Marito [VerfasserIn]
Lesyk, Roman [VerfasserIn]
Buxhofer-Ausch, Veronika [VerfasserIn]
Heibl, Sonja [VerfasserIn]
Pasquier, Florence [VerfasserIn]
Havelange, Violaine [VerfasserIn]
Plo, Isabelle [VerfasserIn]
Vainchenker, William [VerfasserIn]
Kralovics, Robert [VerfasserIn]
Constantinescu, Stefan N [VerfasserIn]

Links:

Volltext

Themen:

Calreticulin
Cytokines
EC 2.7.10.2
Immunologic Factors
Janus Kinase 2
Journal Article

Anmerkungen:

Date Completed 27.02.2023

Date Revised 19.11.2023

published: Print

CommentIn: Blood. 2023 Feb 23;141(8):818-820. - PMID 36821187

Citation Status MEDLINE

doi:

10.1182/blood.2022016846

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM348698933