Involvement of TGFβ1 in autocrine regulation of proplatelet formation in healthy subjects and patients with primary myelofibrosis
Stefania Badalucco,
Christian Andrea Di Buduo,
Rita Campanelli,
Isabella Pallotta,
Paolo Catarsi,
Vittorio Rosti,
David L. Kaplan,
Giovanni Barosi,
Margherita Massa,
Alessandra Balduini
Affiliations
Stefania Badalucco
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
Christian Andrea Di Buduo
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
Rita Campanelli
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy;Center for the Study and the Cure of Myelofibrosis, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
Isabella Pallotta
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy;Department of Biomedical Engineering, Tufts University, Boston, MA, USA
Paolo Catarsi
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy;Center for the Study and the Cure of Myelofibrosis, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
Vittorio Rosti
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy;Center for the Study and the Cure of Myelofibrosis, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
David L. Kaplan
Department of Biomedical Engineering, Tufts University, Boston, MA, USA
Giovanni Barosi
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy;Center for the Study and the Cure of Myelofibrosis, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
Margherita Massa
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy
Alessandra Balduini
Biotechnology Laboratories, Department of Molecular Medicine, University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy;Department of Biomedical Engineering, Tufts University, Boston, MA, USA
Megakaryocytes release platelets into the bloodstream by elongating proplatelets. In this study, we showed that human megakaryocytes constitutively release Transforming Growth Factor β1 and express its receptors. Importantly, Transforming Growth Factor β1 downstream signaling, through SMAD2/3 phosphorylation, was shown to be active in megakaryocytes extending proplatelets, indicating a type of autocrine stimulation on megakaryocyte development. Furthermore, inactivation of Transforming Growth Factor β1 signaling, by the receptor inhibitors SB431542 and Stemolecule ALK5 inhibitor, determined a significant decrease in proplatelet formation. Recent studies indicated a crucial role of Transforming Growth Factor β1 in the pathogenesis of primary myelofibrosis. We demonstrated that primary myelofibrosis-derived megakaryocytes expressed increased levels of bioactive Transforming Growth Factor β1; however, higher levels of released Transforming Growth Factor β1 did not lead to enhanced activation of downstream pathways. Overall, these data propose Transforming Growth Factor β1 as a new element in the autocrine regulation of proplatelet formation in vitro. Despite the increase in Transforming Growth Factor β1 this mechanism seems to be preserved in primary myelofibrosis.