title: Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches.
abstract: The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis.
authors.affiliation: The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Caroline
authors.initials: C
authors.lastname: Baer
authors.affiliation: The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Mario Leonardo
authors.initials: ML
authors.lastname: Squadrito
authors.affiliation: The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland; Department of Molecular, Cell and Developmental Biology and Molecular Biology Institute, University of California, Los Angeles 90095, CA, USA. Electronic address: arispe@mcdb.ucla.edu.
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Iruela-Arispe
authors.affiliation: The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland. Electronic address: michele.depalma@epfl.ch.
authors.forename: Michele
authors.initials: M
authors.lastname: De Palma
mesh_terms: D000818:Animals; D002450:Cell Communication; D002454:Cell Differentiation; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D008264:Macrophages / Q000166:cytology*; D009389:Neovascularization, Pathologic; D018919:Neovascularization, Physiologic
keywords: Angiogenesis; Blood vessel; Exosome; Heterotypic cell interaction; Macrophage; Microvesicle; Monocyte
references.citation: Am J Pathol. 2009 Mar;174(3):1048-64
references.pmid: 19218341
references.citation: Science. 2011 Jun 10;332(6035):1284-8
references.pmid: 21566158
references.citation: Cancer Res. 2006 Dec 1;66(23):11238-46
references.pmid: 17114237
references.citation: Br J Cancer. 1999 Feb;79(5-6):991-5
references.pmid: 10070902
references.citation: Mol Aspects Med. 2011 Apr;32(2):123-45
references.pmid: 21565215
references.citation: Cancer Cell. 2008 Oct 7;14(4):299-311
references.pmid: 18835032
references.citation: Blood. 2012 Jan 19;119(3):756-66
references.pmid: 22031862
references.citation: Hepatology. 2013 Apr;57(4):1416-25
references.pmid: 22815256
references.citation: Invest Ophthalmol Vis Sci. 2010 Jun;51(6):2813-26
references.pmid: 20484600
references.citation: Cancer Cell. 2005 Sep;8(3):211-26
references.pmid: 16169466
references.citation: Cancer Cell. 2011 Apr 12;19(4):512-26
references.pmid: 21481792
references.citation: Nat Rev Immunol. 2002 Aug;2(8):569-79
references.pmid: 12154376
references.citation: Invest Ophthalmol Vis Sci. 2006 Aug;47(8):3595-602
references.pmid: 16877434
references.citation: Cell. 2011 Sep 16;146(6):873-87
references.pmid: 21925313
references.citation: Int J Dev Biol. 2004;48(8-9):1045-58
references.pmid: 15558494
references.citation: Nat Cell Biol. 2000 Oct;2(10):737-44
references.pmid: 11025665
references.citation: Development. 2010 Nov;137(22):3899-910
references.pmid: 20978081
references.citation: Nature. 2011 May 29;474(7352):511-5
references.pmid: 21623369
references.citation: Immunity. 2004 Dec;21(6):831-42
references.pmid: 15589171
references.citation: Vasc Cell. 2012 Sep 03;4(1):15
references.pmid: 22943568
references.citation: Immunology. 2008 Apr;123(4):491-9
references.pmid: 17949417
references.citation: Nature. 1996 Apr 4;380(6573):439-42
references.pmid: 8602242
references.citation: Development. 2007 Dec;134(24):4449-58
references.pmid: 18039971
references.citation: Nat Cell Biol. 2011 Sep 11;13(10):1202-13
references.pmid: 21909098
references.citation: J Exp Med. 2009 May 11;206(5):1089-102
references.pmid: 19398755
references.citation: J Pathol. 2012 May;227(1):4-7
references.pmid: 22367978
references.citation: Nat Med. 2011 Nov 07;17(11):1359-70
references.pmid: 22064426
references.citation: Cell Rep. 2012 Feb 23;1(2):141-54
references.pmid: 22832163
references.citation: Blood. 2010 Jun 17;115(24):5053-6
references.pmid: 20375314
references.citation: J Leukoc Biol. 1994 Mar;55(3):410-22
references.pmid: 7509844
references.citation: Cancer Res. 1996 Oct 15;56(20):4625-9
references.pmid: 8840975
references.citation: J Natl Cancer Inst. 2012 Mar 21;104(6):461-75
references.pmid: 22343031
references.citation: PLoS One. 2011 Jan 10;6(1):e15846
references.pmid: 21264342
references.citation: Proc Natl Acad Sci U S A. 2012 Feb 14;109(7):2491-6
references.pmid: 22308361
references.citation: J Clin Invest. 2004 Sep;114(5):623-33
references.pmid: 15343380
references.citation: Glia. 2013 Jan;61(1):112-20
references.pmid: 22847963
references.citation: Nat Rev Immunol. 2011 Oct 14;11(11):723-37
references.pmid: 21997792
references.citation: Nat Med. 2001 Nov;7(11):1194-201
references.pmid: 11689883
references.citation: Trends Immunol. 2013 Jul;34(7):350-9
references.pmid: 23498847
references.citation: Angiogenesis. 2007;10(2):77-88
references.pmid: 17322966
references.citation: J Immunol. 2007 Aug 1;179(3):1913-25
references.pmid: 17641058
references.citation: Nature. 1977 Oct 27;269(5631):804-6
references.pmid: 927505
references.citation: Nat Rev Immunol. 2009 Apr;9(4):259-70
references.pmid: 19282852
references.citation: Immunity. 2010 May 28;32(5):593-604
references.pmid: 20510870
references.citation: Trends Immunol. 2002 Nov;23(11):549-55
references.pmid: 12401408
references.citation: Mol Cancer. 2011 Sep 22;10:117
references.pmid: 21939504
references.citation: Nature. 2005 Sep 15;437(7057):417-21
references.pmid: 16163358
references.citation: Cancer Res. 2006 Jan 15;66(2):605-12
references.pmid: 16423985
references.citation: Cancer Metastasis Rev. 1999;18(2):215-30
references.pmid: 10728985
references.citation: Cell. 2006 Jan 13;124(1):175-89
references.pmid: 16413490
references.citation: Nature. 1996 Apr 4;380(6573):435-9
references.pmid: 8602241
references.citation: Proc Natl Acad Sci U S A. 1990 Jun;87(12):4828-32
references.pmid: 2191302
references.citation: Blood. 2012 Oct 11;120(15):3152-62
references.pmid: 22919031
references.citation: Int J Dev Biol. 2011;55(4-5):495-503
references.pmid: 21732273
references.citation: Nat Med. 2003 Jun;9(6):789-95
references.pmid: 12740570
references.citation: J Clin Invest. 2012 Mar;122(3):787-95
references.pmid: 22378047
references.citation: Clin Cancer Res. 2013 May 15;19(10):2598-604
references.pmid: 23426276
references.citation: Curr Opin Cell Biol. 2009 Aug;21(4):575-81
references.pmid: 19442504
references.citation: J Exp Med. 2008 Jul 7;205(7):1673-85
references.pmid: 18559453
references.citation: Blood. 2010 Aug 5;116(5):829-40
references.pmid: 20404134
references.citation: Nature. 1997 Mar 6;386(6620):81-4
references.pmid: 9052784
references.citation: Cancer Cell. 2012 Aug 14;22(2):145-52
references.pmid: 22897846
references.citation: Blood. 2004 Jun 1;103(11):4150-6
references.pmid: 14976056
references.citation: Blood. 2013 Mar 21;121(12):2352-62
references.pmid: 23315162
references.citation: Br J Cancer. 2006 Aug 7;95(3):272-81
references.pmid: 16832418
references.citation: Clin Cancer Res. 2011 Aug 15;17(16):5226-32
references.pmid: 21576085
references.citation: Nat Rev Cancer. 2008 Aug;8(8):618-31
references.pmid: 18633355
references.citation: Br J Cancer. 2006 Jan 16;94(1):101-7
references.pmid: 16404363
references.citation: Blood. 2009 Jul 23;114(4):901-14
references.pmid: 19383967
references.citation: J Pathol. 2000 Oct;192(2):150-8
references.pmid: 11004690
references.citation: Mol Cell. 2010 Jul 9;39(1):133-44
references.pmid: 20603081