Conclusions
We confirmed that integrin α5β1, α6β1, α9β1 and αVβ1 actively function on the surface of undifferentiated SSCs derived from outbred ICR mice.
Methods
As a step towards constructing a non-cellular niche supporting the in vitro maintenance of outbred mouse SSC self-renewal, we systematically investigated the types of integrin heterodimers that are expressed transcriptionally, translationally, and functionally in SSCs derived from Imprinting Control Region (ICR) mice.
Results
Among the genes encoding 25 integrin subunits, integrin α1, α5, α6, α9, αV, and αE, and integrin β1 and β5 had significantly higher transcriptional levels than the other subunits. Furthermore, at the translational level, integrin α5, α6, α9, αV, αE, and β1 were localized on the surface of SSCs, but integrin α1 and β5 not. Moreover, significantly stronger translational expression than integrin α9 and αE was observed in integrin α5, α6, αV, and β1. SSCs showed significantly increased adhesion to fibronectin, laminin, tenascin C and vitronectin, and functional blocking of integrin α5β1, α6β1, α9β1 or αVβ1 significantly inhibited adhesion to these molecules. Conclusions: We confirmed that integrin α5β1, α6β1, α9β1 and αVβ1 actively function on the surface of undifferentiated SSCs derived from outbred ICR mice.