Extrahepatic sources of factor VIII potentially contribute to the coagulation cascade correcting the bleeding phenotype of mice with hemophilia A
Diego Zanolini,
Simone Merlin,
Maria Feola,
Gabriella Ranaldo,
Angela Amoruso,
Gianluca Gaidano,
Mauro Zaffaroni,
Alessandro Ferrero,
Sandra Brunelleschi,
Guido Valente,
Sanjeev Gupta,
Maria Prat,
Antonia Follenzi
Affiliations
Diego Zanolini
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Simone Merlin
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Maria Feola
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Gabriella Ranaldo
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Angela Amoruso
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Gianluca Gaidano
Dept. of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
Mauro Zaffaroni
Azienda Ospedaliera Universitaria Maggiore della Carità, SCDU Pediatria, Novara, Italy
Alessandro Ferrero
Azienda Ospedaliera Mauriziano, SC Chirurgia Generale ed Oncologica, Torino, Italy
Sandra Brunelleschi
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Guido Valente
Dept. of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
Sanjeev Gupta
Dept. of Medicine and Pathology, Marion Bessin Liver Research Center, Diabetes Center, Cancer Center, and Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Albert Einstein College of Medicine, Bronx, NY, USA
Maria Prat
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
Antonia Follenzi
Dept. of Health Sciences, Università del Piemonte Orientale “A. Avogadro”, Novara, Italy
A large fraction of factor VIII in blood originates from liver sinusoidal endothelial cells although extrahepatic sources also contribute to plasma factor VIII levels. Identification of cell-types other than endothelial cells with the capacity to synthesize and release factor VIII will be helpful for therapeutic approaches in hemophilia A. Recent cell therapy and bone marrow transplantation studies indicated that Küpffer cells, monocytes and mesenchymal stromal cells could synthesize factor VIII in sufficient amount to ameliorate the bleeding phenotype in hemophilic mice. To further establish the role of blood cells in expressing factor VIII, we studied various types of mouse and human hematopoietic cells. We identified factor VIII in cells isolated from peripheral and cord blood, as well as bone marrow. Co-staining for cell type-specific markers verified that factor VIII was expressed in monocytes, macrophages and megakaryocytes. We additionally verified that factor VIII was expressed in liver sinusoidal endothelial cells and endothelial cells elsewhere, e.g., in the spleen, lungs and kidneys. Factor VIII was well expressed in sinusoidal endothelial cells and Küpffer cells isolated from human liver, whereas by comparison isolated human hepatocytes expressed factor VIII at very low levels. After transplantation of CD34+ human cord blood cells into NOD/SCIDγNull-hemophilia A mice, fluorescence activated cell sorting of peripheral blood showed >40% donor cells engrafted in the majority of mice. In these animals, plasma factor VIII activity 12 weeks after cell transplantation was up to 5% and nine of 12 mice survived after a tail clip-assay. In conclusion, hematopoietic cells, in addition to endothelial cells, express and secrete factor VIII: this information should offer further opportunities for understanding mechanisms of factor VIII synthesis and replenishment.
