Given that the ECM becomes more complex as ECs

Given that the ECM becomes more complex as ECs differentiate, it is of particular interest to understand the outside-in signaling that might modulate their behavior. Similar to other cell types, ECs interact with their environment in large part via the integrin family of adhesion receptors that consists of α and β subunits. The pairing of these two subunits confers specificity of binding to one or more ligands. ECs have been shown to express different integrin heterodimers, including α1β1, α2β1, α3β1, α5β1, αVβ1, αVβ5, α6β1, and αVβ3 (reviewed in Luscinskas and Lawler, 1994). Our analyses showed the highest BMI-1 inhibitor of β1 integrin subunit in both EPCs and mature HUVECs, explaining its indispensable role for cell-cell junction integrity in growing and maturing vasculature (Yamamoto et al., 2015). Among the integrin heterodimers, α5β1 integrin interacts with fibronectin to regulate early vasculogenesis and angiogenesis (Francis et al., 2002). Our results suggested α5β1 integrin as a potential receptor for LN411 and LN421 as well.
Experimental Procedures
Author Contributions
Acknowledgments We thank Ms. Zuhua Cai for producing LN511 in our laboratory, and Ms. Su Ting Tay from Duke-NUS Genome Biology Facility for generating cDNA libraries and running RNA-seq. This work was funded in part by grant NMRC/STaR/0010/2012 from the National Medical Research Council of Singapore. K.T. is a cofounder and shareholder of BioLamina AB.