Anucleate platelets generate progeny.
Platelets are classified as terminally differentiated cells that are incapable of cellular division. However, we observe that anucleate human platelets, either maintained in suspension culture or captured in microdrops, give rise to new cell bodies packed with respiring mitochondria and alpha-granules. Platelet progeny formation also occurs in whole blood cultures. Newly formed platelets are structurally indistinguishable from normal platelets, are able to adhere and spread on extracellular matrix, and display normal signal-dependent expression of surface P-selectin and annexin V. Platelet progeny formation is accompanied by increases in biomass, cellular protein levels, and protein synthesis in expanding populations. Platelet numbers also increase during ex vivo storage. These observations indicate that platelets have a previously unrecognized capacity for producing functional progeny, which involves a form of cell division that does not require a nucleus. Because this new function of platelets occurs outside of the bone marrow milieu, it raises the possibility that thrombopoiesis continues in the bloodstream.
Schwertz
Hansjörg
H
Program in Human Molecular Biology and Genetics, University of Utah, Salt Lake City, Utah 84112, USA.
Köster
Sarah
S
Kahr
Walter H A
WH
Michetti
Noemi
N
Kraemer
Bjoern F
BF
Weitz
David A
DA
Blaylock
Robert C
RC
Kraiss
Larry W
LW
Greinacher
Andreas
A
Zimmerman
Guy A
GA
Weyrich
Andrew S
AS
D017304:Annexin A5 / Q000378:metabolism; D015415:Biomarkers; D001792:Blood Platelets / Q000166:cytology* / Q000378:metabolism* / Q000648:ultrastructure; D049109:Cell Proliferation; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D019007:P-Selectin / Q000378:metabolism*; D010974:Platelet Aggregation; D010976:Platelet Count; D034061:Thrombopoiesis
D017304:Annexin A5; D015415:Biomarkers; D019007:P-Selectin