An integrin-binding array platform identifies αvβ8 and α5β1 integrins on rat primary cortical neurons to support their survival and growth

Abstract

BackgroundIntegrins are the major cell adhesion receptors expressed in almost all cell types connecting the extracellular matrix with cell cytoskeletons and transducing bi-directional signals across cell membranes. In the central nervous system (CNS), integrins are pivotal for CNS cell migration, differentiation, neurite outgrowth and synaptogenesis in both physiological and pathological conditions. Here we studied the effect of different integrin biding peptides for growth and development of primary cortical neurons in vitro. New methodRat primary cortical neurons were cultured in an integrin-binding array platform, which contains immobilized varying short synthetic peptides that bind to 16 individual types of integrin on a 48-well cell culture plate. After cultured for 7 days, cells were fixed and processed for immunostaining with neuronal markers. The overall neuronal growth and neurite outgrowths were quantified. ResultsWe found that binding peptides for integrin αvβ8, α5β1 and α3β1 particularly the former two provided superior condition for neuronal growth, survival and maturation. Moreover, optimal neurite outgrowth was observed when neurons were cultured in 3-dimension using injectable hydrogel along with binding peptide for αvβ8 or α5β1 integrins. Comparison with existing methodFor primary neuronal culture, poly-D-lysine coating is conventional method to support cell attachment. Our study has demonstrated that selected integrin binding peptides provide greater support for the growth of cultured primary neurons. ConclusionThese data suggest that integrin αvβ8 and α5β1 are conducive for survival, growth and maturation of primary cortical neurons. This information could be utilized in designing combinational biomaterial and cell-based therapy for neural regeneration following brain injury.