Release Profile of Exogenous SDF-1 Differentially Affects Cortical SDF-1/CXCR4 Signaling In Vivo

摘要

Conclusions: Our data suggests that the manner of AFSDF-1 presentation significantly affected activation of CXCR4 at day 1 (Fig. 1D, E) despite having similar protein payloads over the first 24 hrs (~30ng for both bolus and sustained release groups). Moreover, the transient nature of widespread CXCR4 activation for the AFSDF-1 NP groups (Fig. 1E) indicates controlled protein release does not necessarily translate to sustained biochemical effects (i.e. prolonged CXCR4~+ cell recruitment). Instead, cytokine/receptor auto-regulatory mechanisms may demand more complex release profiles (i.e. delayed and/or pulsed release) to achieve sustained cellular response. Further studies will include cell phenotype characterization of CXCR4~+ cells and evaluations in an injured cortical microenvironment.