TY - JOUR
T1 - Context- and Cell-Dependent Effects of Delta-Like 4 Targeting in the Bone Marrow Microenvironment
AU - Remédio, Leonor
AU - Carvalho, Tânia
AU - Caiado, Francisco
AU - Bastos-Carvalho, Ana
AU - Martins, Diana
AU - Duarte, António
AU - Yagita, Hideo
AU - Dias, Sergio
N1 - info:eu-repo/grantAgreement/FCT/3599-PPCDT/113617/PT#
This work was supported by FCT PTDC/SAU-ORG/113617/2009 (www.fct.pt). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
The authors would like to thank other members of the Angiogenesis Lab for their input and suggestions. The Program for Advanced Medical Education is sponsored by Fundacao Calouste Gulbenkian, Fundacao Champalimaud, Ministerio da Saude and Fundacao para a Ciencia e Tecnologia, Portugal.
PY - 2012/12/20
Y1 - 2012/12/20
N2 - Delta-like 4 (Dll4) is a ligand of the Notch pathway family which has been widely studied in the context of tumor angiogenesis, its blockade shown to result in non-productive angiogenesis and halted tumor growth. As Dll4 inhibitors enter the clinic, there is an emerging need to understand their side effects, namely the systemic consequences of Dll4:Notch blockade in tissues other than tumors. The present study focused on the effects of systemic anti-Dll4 targeting in the bone marrow (BM) microenvironment. Here we show that Dll4 blockade with monoclonal antibodies perturbs the BM vascular niche of sub-lethally irradiated mice, resulting in increased CD31+, VE-Cadherin+ and c-kit+ vessel density, and also increased megakaryocytes, whereas CD105+, VEGFR3+, SMA+ and lectin+ vessel density remained unaltered. We investigated also the expression of angiocrine genes upon Dll4 treatment in vivo, and demonstrate that IGFbp2, IGFbp3, Angpt2, Dll4, DHH and VEGF-A are upregulated, while FGF1 and CSF2 are reduced. In vitro treatment of endothelial cells with anti-Dll4 reduced Akt phosphorylation while maintaining similar levels of Erk 1/2 phosphorylation. Besides its effects in the BM vascular niche, anti-Dll4 treatment perturbed hematopoiesis, as evidenced by increased myeloid (CD11b+), decreased B (B220+) and T (CD3+) lymphoid BM content of treated mice, with a corresponding increase in myeloid circulating cells. Moreover, anti-Dll4 treatment also increased the number of CFU-M and -G colonies in methylcellulose assays, independently of Notch1. Finally, anti-Dll4 treatment of donor BM improved the hematopoietic recovery of lethally irradiated recipients in a transplant setting. Together, our data reveals the hematopoietic (BM) effects of systemic anti-Dll4 treatment result from qualitative vascular changes and also direct hematopoietic cell modulation, which may be favorable in a transplant setting.
AB - Delta-like 4 (Dll4) is a ligand of the Notch pathway family which has been widely studied in the context of tumor angiogenesis, its blockade shown to result in non-productive angiogenesis and halted tumor growth. As Dll4 inhibitors enter the clinic, there is an emerging need to understand their side effects, namely the systemic consequences of Dll4:Notch blockade in tissues other than tumors. The present study focused on the effects of systemic anti-Dll4 targeting in the bone marrow (BM) microenvironment. Here we show that Dll4 blockade with monoclonal antibodies perturbs the BM vascular niche of sub-lethally irradiated mice, resulting in increased CD31+, VE-Cadherin+ and c-kit+ vessel density, and also increased megakaryocytes, whereas CD105+, VEGFR3+, SMA+ and lectin+ vessel density remained unaltered. We investigated also the expression of angiocrine genes upon Dll4 treatment in vivo, and demonstrate that IGFbp2, IGFbp3, Angpt2, Dll4, DHH and VEGF-A are upregulated, while FGF1 and CSF2 are reduced. In vitro treatment of endothelial cells with anti-Dll4 reduced Akt phosphorylation while maintaining similar levels of Erk 1/2 phosphorylation. Besides its effects in the BM vascular niche, anti-Dll4 treatment perturbed hematopoiesis, as evidenced by increased myeloid (CD11b+), decreased B (B220+) and T (CD3+) lymphoid BM content of treated mice, with a corresponding increase in myeloid circulating cells. Moreover, anti-Dll4 treatment also increased the number of CFU-M and -G colonies in methylcellulose assays, independently of Notch1. Finally, anti-Dll4 treatment of donor BM improved the hematopoietic recovery of lethally irradiated recipients in a transplant setting. Together, our data reveals the hematopoietic (BM) effects of systemic anti-Dll4 treatment result from qualitative vascular changes and also direct hematopoietic cell modulation, which may be favorable in a transplant setting.
KW - HEMATOPOIETIC STEM-CELL
KW - ; SINUSOIDAL ENDOTHELIAL-CELLS
KW - INHIBITS TUMOR-GROWTH
KW - NOTCH LIGAND
KW - IN-VIVO
KW - PROGENITOR CELLS
KW - VASCULAR NICHE
KW - SELF-RENEWAL
KW - INDUCED MOBILIZATION
KW - LINEAGE COMMITMENT
UR - http://www.scopus.com/inward/record.url?scp=84871412471&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0052450
DO - 10.1371/journal.pone.0052450
M3 - Article
C2 - 23285048
AN - SCOPUS:84871412471
SN - 1932-6203
VL - 7
SP - Online
JO - PLoS ONE
JF - PLoS ONE
IS - 12
M1 - e52450
ER -