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Related Experiment Video

Updated: Oct 26, 2025

Purification of Platelets from Mouse Blood

Purification of Platelets from Mouse Blood

Published on: May 7, 2019

Bleeding diathesis in mice lacking JAK2 in platelets.

Nathan Eaton^1,2, Saravanan Subramaniam¹, Marie L Schulte¹

¹Versiti Blood Research Institute, Milwaukee, WI.

|August 3, 2021

Summary

This summary is machine-generated.

Janus kinase 2 (JAK2) plays a key role in platelet function and hemostasis. Deleting JAK2 in platelets impairs thrombus formation and causes bleeding, suggesting JAK2 signaling impacts hemostatic function.

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Last Updated: Oct 26, 2025

Purification of Platelets from Mouse Blood

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Published on: May 7, 2019

Proplatelet Formation Dynamics of Mouse Fresh Bone Marrow Explants

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Published on: May 20, 2021

Real-time Imaging of Heterotypic Platelet-neutrophil Interactions on the Activated Endothelium During Vascular Inflammation and Thrombus Formation in Live Mice

Real-time Imaging of Heterotypic Platelet-neutrophil Interactions on the Activated Endothelium During Vascular Inflammation and Thrombus Formation in Live Mice

Published on: April 2, 2013

Area of Science:

Hematology
Molecular Biology
Thrombosis Research

Background:

Janus kinase 2 (JAK2) is crucial in JAK/STAT signaling pathways within hematopoietic cells.
The JAK2 V617F mutation is linked to myeloproliferative neoplasms (MPNs) and thrombosis.
The precise role of JAK2 in platelet hemostasis is not fully understood.

Purpose of the Study:

To investigate the function of JAK2 in platelet hemostatic capabilities.
To elucidate the impact of JAK2 deficiency on platelet activation and aggregation.

Main Methods:

Utilized Jak2fl/fl Pf4-Cre (Jak2Plt-/-) mice with JAK2 specifically deleted in platelets and megakaryocytes.
Assessed hemostatic function using ferric chloride carotid artery injury and cremaster muscle laser-induced injury models.
Analyzed platelet adhesion, thrombus formation, α-granule secretion, integrin activation, and intracellular signaling.

Main Results:

Jak2Plt-/- mice exhibited thrombocytosis, splenomegaly, and severe bleeding tendencies.
JAK2-deficient platelets showed impaired thrombus formation on collagen under arterial shear.
Platelets lacking JAK2 displayed reduced α-granule release and integrin αIIbβ3 activation upon stimulation via GPVI, but not thrombin.

Conclusions:

JAK2 deletion significantly impairs platelet immunoreceptor tyrosine-based activation motif (ITAM) signaling and overall hemostatic function in mice.
Aberrant JAK2 signaling in MPNs may contribute to hemostatic defects by affecting GPVI signaling pathways.